WO2018128401A1

WO2018128401A1 - Uplink control information transmission method and device

Info

Publication number: WO2018128401A1
Application number: PCT/KR2018/000154
Authority: WO
Inventors: 김철순; 이준환; 이정훈; 김지형; 문성현; 박주호; 김태중; 김민현
Original assignee: 한국전자통신연구원
Priority date: 2017-01-06
Filing date: 2018-01-04
Publication date: 2018-07-12

Abstract

The present invention relates to an uplink control information transmission method and device which can improve channel estimation performance of a base station. A terminal operation method for transmitting uplink control information to a base station, according to an embodiment of the present invention, comprises the steps of: receiving, from the base station, resource location information for transmission of a UCI channel; mapping UCI to at least one symbol on the basis of the resource location information, and mapping a reference signal in consideration of frequency selection characteristics and time selection characteristics of a wireless channel; and transmitting, to the base station, a subframe including the at least one symbol.

Description

Method and apparatus for transmitting uplink control information

The present invention relates to uplink control information of a wireless communication system and relates to a method and apparatus for transmitting uplink control information for improving channel estimation performance in a base station.

In a general wireless communication system, information transmitted from a terminal to a base station is referred to as UL control information (UCI). Examples of such UCI include a scheduling request requested by the terminal to a base station, a downlink channel quality indicator, and an acknowledgment of DL data.

Since the new radio communication system supports dynamic time division duplex (TDD), beam-centric communication, or low latency communication, the number of UL symbols that a UE allows for transmission of UCI may be variable and limited. .

For example, when the number of UL symbols is variable, the number of UL symbols may be indicated to the terminal through higher layer signaling of the base station. The UL symbol may be indicated to the terminal through a combination of scheduling information of the base station and higher layer signaling. It may also indicate the number of.

As an example of a limited number of UL symbols, a base station operating in TDD may limit the number of symbols belonging to UL to a few in order to more effectively support traffic of DL in a corresponding slot. Therefore, in the NR communication system, the physical channel for transmitting UCI may be variable in time dimension, and should also be able to operate with a small amount of time dimension.

The present invention for solving the above problems, the terminal can vary the time resources for the transmission of the uplink control information (UCI), the terminal transmits uplink control information that can transmit the UCI with a small amount of time resources It is a technical object to provide a method and apparatus.

The present invention for solving the above problems, the UE does not use the reference signal (RS) when transmitting the UCI channel, by mapping the HARQ-ACK bit using the resource element (RE) of the UCI channel in the base station It is a technical object of the present invention to provide a method and apparatus for transmitting uplink control information that can reduce a detection error.

According to the present invention for solving the above problems, the UE uses a reference signal (RS) when transmitting the UCI channel, and the first symbol and the second symbol has a different subcarrier index set to the base station of the UCI channel It is a technical problem to provide a method and apparatus for transmitting uplink control information for improving detection performance.

The present invention for solving the above problems, the base station is configured in the base station to allow the transmission of the sounding reference signal (SRS) in the same subband as the UCI channel for transmitting the scheduling request (SR), the first terminal is a UCI channel And the second terminal applies a transmission comb (TC) to the UCI channel when transmitting a sounding reference signal (SRS) to prevent collision between the UCI channel and the sounding reference signal (SRS). It is a technical problem to provide a control information transmission method and apparatus.

The present invention for solving the above problems, the terminal can improve the channel estimation performance in the base station by repeatedly transmitting the sounding reference signal (SRS) to the base station with the same resources (frequency and code) for two symbols It is a technical problem to provide a method and apparatus for transmitting uplink control information.

In order to solve the above problems, the present invention obtains channel state information (CSI) from a base station by repeatedly transmitting a sounding reference signal (SRS) to a base station with different resources (frequency and code) for two symbols. It is a technical problem to provide a method and apparatus for transmitting uplink control information that can reduce time.

The present invention for solving the above problems, by applying a sounding reference signal (occasion) to perform the uplink management between the terminal and the base station can be managed so that the uplink is not broken even in a communication environment with a high probability of failure. It is an object of the present invention to provide a method and apparatus for transmitting uplink control information.

The present invention for solving the above problems, the base station to allocate the frequency resources used in the terminals from the edge, and the terminal transmits a lot of data using a wide bandwidth by transmitting the UL data channel in the DFT-s-OFDM waveform It is a technical object of the present invention to provide a method and apparatus for transmitting uplink control information capable of transmitting data.

The present invention for solving the above problems, the uplink control information that can reduce the time to obtain the channel state information (CSI) in the base station by transmitting a sounding reference signal (SRS) in a broadband station is located close to the base station It is a technical problem to provide a transmission method and apparatus.

The present invention for solving the above problems, the base station to match the center frequency of the terminal, the method for transmitting uplink control information that the terminal can perform a more flexible resource allocation by transmitting the UL data channel to the CP-OFDM and It is a technical object to provide an apparatus.

A method of operating a terminal according to an embodiment of the present invention for achieving the above object, in the method of operating a terminal for transmitting uplink control information to a base station, the resource location for the transmission of the uplink control information (UCI) channel from the base station Receiving information, mapping UCI to at least one symbol based on the resource location information, mapping a reference signal in consideration of a frequency selection characteristic and a time selection characteristic of a radio channel, and at least one symbol The method may include transmitting a subframe including the to the base station.

In the method of operating a terminal according to an embodiment of the present disclosure, in the mapping of the reference signal, the reference signal may be mapped to all subcarriers of one symbol in consideration of the frequency selection characteristic.

In the method of operating a terminal according to an embodiment of the present disclosure, in the step of mapping the reference signal, the reference signal may be uniformly mapped to subcarriers of a plurality of symbols in consideration of the time selection characteristic.

In an operation method of a terminal according to an embodiment of the present disclosure, in the mapping of the UCI, the resource location information may include time resource location information and frequency resource location information for transmission of the UCI channel. The UCI may be mapped in the time resource order, and then the UCI may be mapped in the frequency resource order.

In an operation method of a terminal according to an embodiment of the present disclosure, in the mapping of the UCI, the resource location information may include time resource location information and frequency resource location information for transmission of the UCI channel. The UCI may be mapped in the frequency resource order, and then the UCI may be mapped in the time resource order.

In an operation method of a terminal according to an embodiment of the present disclosure, the time resource location information may indicate at least one subslot configured of one or more symbols.

In the method of operating a terminal according to an embodiment of the present disclosure, the frequency resource position may be generated based on a transmission comb (TC) value, a bandwidth setting variable, a frequency hopping bandwidth variable, and frequency domain position information.

In a method of operating a terminal according to an embodiment of the present disclosure, the resource location information may be received from the base station through downlink control information (DCI).

In an operation method of a terminal according to an embodiment of the present disclosure, the resource location information may be received from the base station through RRC (Radio Resource Control) signaling.

In a method of operating a terminal according to an embodiment of the present disclosure, the resource location information may be received from the base station through a bit field included in a downlink control channel.

According to an aspect of the present invention, there is provided a method of operating a terminal for transmitting uplink control information to a base station, the method comprising: receiving scheduling request resources for a plurality of service types from the base station; Selecting a service type to be provided from among the plurality of service types, mapping uplink control information (UCI) and a reference signal for the selected service type to a scheduling request resource allocated by the base station, and the UCI ( And transmitting a subframe including the uplink control information) and the reference signal to the base station.

In a method of operating a terminal according to an embodiment of the present invention, in the step of receiving the scheduling request resource, each of an enhanced mobile broadband (eMBB), ultra-reliable low-latency communication (URLLC), and a massive machine type communications (mMTC) service May receive a scheduling request resource of.

In an operation method of a terminal according to an embodiment of the present invention, in the step of mapping to a scheduling request resource, the scheduling of the uplink control information (UCI) and the reference signal of a service selected from among the eMBB service, the URLLC service, and the mMTC service is performed. You can map to the request resource.

In the method of operating a terminal according to an embodiment of the present disclosure, the scheduling request resource indicates each of a plurality of subslots allocated to different frequency resources, and each of the plurality of subslots may be configured of a plurality of symbols. Can be. In the mapping to the scheduling request resource, the UIC and the reference signal may be mapped differently from positions of frequency resources of the plurality of subslots.

A terminal according to an embodiment of the present invention for achieving the above object is a terminal for transmitting uplink control information to a base station, a memory for storing at least one program, a processor for performing the at least one program command, a network and It includes a transceiver for connecting and performing communication. Here, the at least one program command receives resource location information for transmission of an uplink control information (UCI) channel from the base station, maps UCI to at least one symbol based on the resource location information, and wireless channel The reference signal may be mapped in consideration of the frequency selection characteristic and the time selection characteristic, and the subframe including the at least one symbol may be transmitted to the base station.

In the terminal according to an exemplary embodiment of the present disclosure, the at least one program command may map the reference signal to all subcarriers of one symbol in consideration of the frequency selection characteristic, or a plurality of symbols in consideration of the time selection characteristic. May be performed to map the reference signal to some subcarriers of the.

In the terminal according to an embodiment of the present disclosure, the at least one program command maps resource elements of the UCI channel in the order of time resources included in the resource location information, and subsequently, frequency resources included in the resource location information. Map the resource elements of the UCI channel in order, or map the resource elements of the UCI channel in the order of frequency resources included in the resource location information, and subsequently, the UCI channel in the order of time resources included in the resource location information. It can be executed to map the resource elements of.

In the terminal according to an embodiment of the present disclosure, the at least one program command may be executed to receive the resource location information from the base station through downlink control information (DCI).

In the terminal according to an embodiment of the present disclosure, the at least one program command may be executed to receive the resource location information from the base station through RRC (Radio Resource Control) signaling.

In the terminal according to an embodiment of the present disclosure, the at least one program command may be executed to receive the resource position information from the base station through a bit field included in a downlink control channel.

According to the present invention, a time resource for transmitting uplink control information (UCI) may be changed in a terminal, and the UE may transmit a UCI with a small amount of time resource.

According to the present invention, the UE can reduce the detection error of the UCI channel in the base station by mapping the HARQ-ACK bit using the resource element (RE) without using the reference signal (RS) when transmitting the UCI channel.

According to the present invention, the UE uses the reference signal (RS) when transmitting the UCI channel, and the first symbol and the second symbol can have a different subcarrier index set to increase the detection performance of the UCI channel at the base station.

According to the present invention, the base station is configured to allow transmission of the sounding reference signal (SRS) in the same subband as the UCI channel transmitting the scheduling request (SR), the first terminal transmits the UCI channel, the second terminal In the case of transmitting the sounding reference signal (SRS), it is possible to prevent a collision between the UCI channel and the sounding reference signal (SRS) by applying a TC (Transmission Comb) to the UCI channel.

According to the present invention, the terminal repeatedly transmits a sounding reference signal (SRS) to the base station with the same resource (frequency and code) for two symbols, thereby improving channel estimation performance at the base station.

According to the present invention, it is possible to reduce the time for the terminal to obtain the channel state information (CSI) by repeatedly transmitting the sounding reference signal (SRS) to the base station with different resources (frequency and code) for two symbols.

According to the present invention, uplink management is performed between a terminal and a base station by applying a sounding reference signal occsion, so that the uplink may be managed even in a communication environment having a high probability of failure.

According to the present invention, the base station allocates the frequency resources used by the terminals from the edge, and the terminal can transmit a lot of data using a wide bandwidth by transmitting the UL data channel in the DFT-s-OFDM waveform. In addition, the terminal located near the base station transmits the sounding reference signal (SRS) over a broadband, thereby reducing the time to obtain the channel state information (CSI) from the base station.

According to the present invention, the base station matches the center frequency of the terminals, the terminal can reduce the Peak to Average Power Ratio (PAPR) by transmitting the UL data channel to the CP-OFDM.

1 is a conceptual diagram illustrating a first embodiment of a communication system.

2 is a block diagram showing a first embodiment of a communication node constituting a communication system.

FIG. 3 is a diagram illustrating a resource element to which an uplink control information (UCI) channel or a UCI channel and a reference signal are allocated.

4 is a diagram illustrating an example of mapping two symbols and twelve subcarriers.

5 is a diagram illustrating another example of mapping two symbols and twelve subcarriers.

FIG. 6 is a diagram illustrating a method for allocating a resource element RE of a reference signal RS to a specific symbol and a specific subcarrier.

FIG. 7 is a diagram illustrating a method for uniformly allocating a resource element RE of a reference signal RS to symbols and subcarriers.

8 is a diagram illustrating a method of allocating a resource element RE of a reference signal RS to all subcarriers of a specific symbol.

9 is a diagram illustrating a UCI channel configured with a reference signal (RS) resource element (RE).

FIG. 10 is a diagram illustrating a UCI channel in which a ZP (zero power) reference signal (RS) is additionally set.

FIG. 11 is a diagram illustrating a method for allocating resource elements when a UCI channel and data coexist in a symbol.

FIG. 12 is a diagram illustrating that when a UCI channel of a first terminal and data of a second terminal coexist in a subslot, a part of a UCI channel of a first terminal and a part of data of a second terminal overlap each other.

FIG. 13 is a diagram illustrating a slot in which a UCI channel and a sounding reference signal (SRS) coexist.

14 is a diagram illustrating an example of arranging 3 comb of the sounding reference signal SRS.

15 is a diagram illustrating an example of allocating a UCI channel to a resource block (RB).

16 is a diagram illustrating another example of allocating a UCI channel to a resource block (RB).

17 illustrates an example of a UCI channel in which two sounding reference signal (SRS) resources are allocated to UCI.

18 is a diagram illustrating a method of mapping a first sounding reference signal (SRS) resource and a second sounding reference signal (SRS) resource to one UCI resource.

19 illustrates a method of mapping a first sounding reference signal (SRS) resource to a first UCI resource and a second sounding reference signal (SRS) resource to a second UCI resource.

20 is a diagram illustrating a first embodiment in which a UCI channel is configured with 48 subcarriers.

FIG. 21 is a diagram illustrating a second embodiment in which a UCI channel is configured with 48 subcarriers.

FIG. 22 is a diagram illustrating a third embodiment in which a UCI channel is configured with 48 subcarriers.

FIG. 23 is a diagram illustrating a fourth embodiment in which a UCI channel is configured with 48 subcarriers.

FIG. 24 illustrates a first embodiment of configuring a sounding reference signal (SRS) resource pool and a UCI channel resource pool.

FIG. 25 illustrates a second embodiment of configuring a sounding reference signal (SRS) resource pool and a UCI channel resource pool.

FIG. 26 is a diagram illustrating a third embodiment of configuring a sounding reference signal (SRS) resource pool and a UCI channel resource pool.

27 is a diagram illustrating an example of a sounding reference signal (SRS) occasion for a single terminal.

FIG. 28 is a diagram illustrating a first embodiment of multiplexing an uplink (UL) data channel and a sounding reference signal (SRS) occasion.

FIG. 29 is a diagram illustrating a second embodiment of multiplexing an uplink (UL) data channel and a sounding reference signal (SRS) occasion.

30 illustrates a third embodiment of multiplexing an uplink (UL) data channel and a sounding reference signal (SRS) occasion.

31 is a diagram illustrating an example of a UCI channel to which subslot aggregation is applied.

32 is a diagram illustrating an example of a subband for a UCI channel in an UL bandwidth configured for a terminal.

33 is a diagram illustrating another example of a subband for a UCI channel in an UL bandwidth configured for a terminal.

34 is a diagram illustrating a method of assigning UL bands that match edges of frequencies.

35 is a diagram illustrating a method for allocating an UL band for matching the center of frequency.

36 is a diagram illustrating an example of a UCI channel using the same subband.

FIG. 37 is a diagram illustrating an example of a UCI channel in which a ZP (Zero Power) reference signal (RS) resource is set differently for each symbol in the same subband.

38 is a diagram illustrating an example of a UCI channel using a reference signal RS as the same subcarrier set in the same subband.

FIG. 39 is a diagram illustrating an example of a UCI channel using a reference signal RS as a different subcarrier set in the same subband.

40 is a diagram illustrating an example of a UCI channel using different subbands.

41 is a diagram illustrating a multi-cluster transmission method for obtaining a multiplexing gain.

42 illustrates an example of a method for transmitting uplink control information according to the present invention.

43 is a diagram illustrating another example of a method for transmitting uplink control information according to the present invention.

As the present invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all changes, equivalents, and substitutes included in the spirit and scope of the present invention.

Terms such as first and second may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component. The term and / or includes a combination of a plurality of related items or any item of a plurality of related items.

When a component is referred to as being "connected" or "connected" to another component, it may be directly connected to or connected to that other component, but it may be understood that other components may be present in between. Should be. On the other hand, when a component is said to be "directly connected" or "directly connected" to another component, it should be understood that there is no other component in between.

The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this application, the terms "comprise" or "have" are intended to indicate that there is a feature, number, step, operation, component, part, or combination thereof described in the specification, and one or more other features. It is to be understood that the present invention does not exclude the possibility of the presence or the addition of numbers, steps, operations, components, components, or a combination thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art and shall not be construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Hereinafter, with reference to the accompanying drawings, it will be described in detail a preferred embodiment of the present invention. In the following description of the present invention, the same reference numerals are used for the same elements in the drawings and redundant descriptions of the same elements will be omitted.

Throughout the specification, a terminal includes a mobile station (MS), a mobile terminal (MT), an advanced mobile station (AMS), a high reliability mobile station (HR-MS). ), Subscriber station (SS), portable subscriber station (PSS), access terminal (AT), user equipment (user equipment), machine type communication device, MTC device) and the like, and may include all or some functions of MT, MS, AMS, HR-MS, SS, PSS, AT, UE, and the like.

In addition, a base station (BS) may be an advanced base station (ABS), a high reliability base station (HR-BS), a node B (node B), an advanced node B (evolved node B, eNodeB), access point (AP), radio access station (RAS), base transceiver station (BTS), mobile multihop relay (MMR) -BS, relay serving as a base station station (RS), relay node (RN) serving as base station, advanced relay station (ARS) serving as base station, high reliability relay station (HR) serving as base station -RS), small base station (femto BS, home node B (HNB), home eNodeB (HeNB), pico base station (pico BS), macro base station (macro BS), micro base station (micro BS) ), Etc., and all or one of ABS, Node B, eNodeB, AP, RAS, BTS, MMR-BS, RS, RN, ARS, HR-RS, small base station, and the like. It may also include negative functions.

The base station configures one or several cells, and the terminal establishes an RRC connection with at least one cell of the base station. Herein, a cell having an RRC connection is referred to as a serving cell.

Referring to FIG. 1, the communication system 100 includes a plurality of communication nodes 110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). Here, the communication system 100 may be referred to as a "communication network". Each of the plurality of communication nodes may support at least one communication protocol. For example, each of the plurality of communication nodes may include a code division multiple access (CDMA) based communication protocol, a wideband CDMA (WCDMA) based communication protocol, a time division multiple access (TDMA) based communication protocol, and a frequency division multiple (FDMA) based communication protocol. access based communication protocol, orthogonal frequency division multiplexing (OFDM) based communication protocol, orthogonal frequency division multiple access (OFDMA) based communication protocol, single carrier (SC) -FDMA based communication protocol, non-orthogonal multiple An access based communication protocol and a space division multiple access (SDMA) based communication protocol may be supported. Each of the plurality of communication nodes may have a structure as follows.

Referring to FIG. 2, the communication node 200 may include at least one processor 210, a memory 220, and a transceiver 230 that communicates with a network. In addition, the communication node 200 may further include an input interface device 240, an output interface device 250, a storage device 260, and the like. Each component included in the communication node 200 may be connected by a bus 270 to communicate with each other.

The processor 210 may execute a program command stored in at least one of the memory 220 and the storage device 260. The processor 210 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present invention are performed. Each of the memory 220 and the storage device 260 may be configured as at least one of a volatile storage medium and a nonvolatile storage medium. For example, the memory 220 may be configured as at least one of a read only memory (ROM) and a random access memory (RAM).

Referring back to FIG. 1, the communication system 100 includes a plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2, and a plurality of user equipments. ) 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may form a macro cell. Each of the fourth base station 120-1 and the fifth base station 120-2 may form a small cell. The fourth base station 120-1, the third terminal 130-3, and the fourth terminal 130-4 may belong to the coverage of the first base station 110-1. The second terminal 130-2, the fourth terminal 130-4, and the fifth terminal 130-5 may belong to the coverage of the second base station 110-2. The fifth base station 120-2, the fourth terminal 130-4, the fifth terminal 130-5, and the sixth terminal 130-6 may belong to the coverage of the third base station 110-3. . The first terminal 130-1 may belong to the coverage of the fourth base station 120-1. The sixth terminal 130-6 may belong to the coverage of the fifth base station 120-2.

Here, each of the base stations 110-1, 110-2, 110-3, 120-1, and 120-2 is a NodeB, an evolved NodeB, a base transceiver station (BTS), Radio base station, radio transceiver, access point, access node, road side unit (RSU), radio remote head (RRH), transmission point (TP) It may be referred to as a transmission and reception point (TRP), a relay node, and the like. Each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 is a terminal, an access terminal, a mobile terminal, It may be referred to as a station, a subscriber station, a mobile station, a portable subscriber station, a node, a device, or the like.

A plurality of communication nodes 110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6 Each may support cellular communication (eg, long term evolution (LTE), LTE-A (advanced, etc.) as defined in the 3rd generation partnership project (3GPP) standard). Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may operate in different frequency bands, or may operate in the same frequency band. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to each other through an ideal backhaul or a non-ideal backhaul, and an ideal backhaul. Alternatively, information can be exchanged with each other via non-ideal backhaul. Each of the base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to a core network (not shown) through an ideal backhaul or a non-idal backhaul. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 receives a signal received from the core network, corresponding terminal 130-1, 130-2, 130-3, 130. -4, 130-5, 130-6, and the signal received from the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) core network Can be sent to.

Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may support downlink transmission based on OFDMA and uplink based on SC-FDMA. Can support transport. In addition, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may transmit multiple input multiple output (MIMO) (eg, single user (SU) -MIMO, Multi-user (MU) -MIMO, massive MIMO), CoMP (coordinated multipoint) transmission, carrier aggregation transmission, transmission in unlicensed band, device to device, D2D ) Communication (or ProSeimity services). Here, each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 is a base station 110-1, 110-2, 110-3, 120-1 , 120-2), and operations supported by the base stations 110-1, 110-2, 110-3, 120-1, and 120-2.

For example, the second base station 110-2 may transmit a signal to the fourth terminal 130-4 based on the SU-MIMO scheme, and the fourth terminal 130-4 may transmit the signal based on the SU-MIMO scheme. The signal may be received from the second base station 110-2. Alternatively, the second base station 110-2 may transmit a signal to the fourth terminal 130-4 and the fifth terminal 130-5 based on the MU-MIMO scheme, and the fourth terminal 130-4 may be used. And each of the fifth terminals 130-5 may receive a signal from the second base station 110-2 by the MU-MIMO scheme. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may transmit a signal to the fourth terminal 130-4 based on a CoMP scheme, and a fourth The terminal 130-4 may receive a signal from the first base station 110-1, the second base station 110-2, and the third base station 110-3 by the CoMP scheme. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 includes terminals 130-1, 130-2, 130-3, 130-4, which belong to its own coverage. 130-5 and 130-6) and a signal may be transmitted and received based on a carrier aggregation scheme. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 coordinates D2D communication between the fourth terminal 130-4 and the fifth terminal 130-5. The fourth terminal 130-4 and the fifth terminal 130-5 may each perform D2D communication by coordination of each of the second base station 110-2 and the third base station 110-3. Can be performed.

The NR (New Radio) communication system may configure dual connectivity (DC) and carrier aggregation (CA) for a terminal by operating one or more carriers. To support this, a physical channel transmitting UL (Uplink) HARQ-ACK when a single carrier is configured and a physical channel transmitting UL (UL) HARQ-ACK when a DC or CA is configured can be used. have.

In an NR communication system, a base station (BS) may subcarrie one transport block into one unit, which may be referred to as a codeword (CW). The base station transmits the codeword CW to the terminal, and the terminal may receive the codeword CW from the base station. The terminal may generate one HARQ-ACK bit for each codeword (CW) or codeblock group (CBg). In this case, when the base station transmits data using MIMO (Multiple Input Multiple Output), the base station may transmit one or two codewords (CW) to the terminal according to the state of the channel. Alternatively, the base station may set at least one code block group CBg including one or two codewords CW and may transmit at least one set of code block groups CBg to the terminal.

When the base station configures a single carrier to the terminal, the terminal may generate HARQ-ACK of 1 bit or 2 bits. In addition, when the base station sets a plurality of carriers to the terminal, the terminal may generate feedback bits by channel coding the HARQ-ACK bits. The UE may transmit an uplink (UL) HARQ-ACK in a time resource indicated by uplink (UL) signaling or a combination of scheduling and uplink (UL) signaling from the base station. The UL time resource indicated by the base station to the terminal may include a slot index, a subslot index, or a symbol index.

The uplink (UL) control channel transmitted by the terminal may occupy at least one symbol according to a combination of a higher layer configuration and a downlink (DL) control channel scheduling downlink data. Such a plurality of consecutive symbols may be referred to as an uplink (UL) sub-slot or a mini-slot. The base station may instruct the terminal in a higher layer configuration UL control channel having one or more subslots according to the scenario. In order to support this, one or more HARQ-ACK bits may be included in the UL control channel (UCI channel), and may include channel state information or scheduling request. have. In some cases, the terminal may transmit an uplink (UL) control channel to report an uplink (UL) buffer state to the base station.

The method of transmitting a UCI channel having one symbol may be classified according to the presence or absence of a reference signal (RS or reference signal). If the reference signal RS is not used, an area of a given constant radio resource and UCI bits may be mapped in a predetermined method. Since the base station does not have a reference signal (RS), in the process of demodulating these UCI bits, the base station may use a pattern of a UCI channel previously promised with the terminal.

Here, since the radio resource areas are discretely distributed, the pattern of the UCI channel previously promised with the terminal may be expressed in the form of a sequence. If the UCI is HARQ-ACK, the base station may determine an ACK when detecting a specific sequence, and may determine a NACK when detecting another specific sequence. Here, the UCI may be in the form of on / off shift keying (OOK) that specifies the presence or absence of a scheduling request or may be transmitted together with a HARQ-ACK bit.

In the case of using the reference signal (RS), since a certain radio resource region of a given symbol and a subcarrier is shared by the reference signal (RS) and the HARQ-ACK bit, a method of appropriately multiplexing it may be necessary. For orthogonal distribution, time division distribution (TDM), frequency division distribution (FDM), and the like may be considered. In addition, in the case of non-orthogonal distribution, space division distribution (SDM), code division distribution (CDM), and power division distribution may be considered. In the non-orthogonal distribution, it is difficult for the base station to estimate an uplink (UL) channel using the reference signal (RS), so the detection performance of the HARQ-ACK bit must be optimized to maintain a tradeoff. However, since there are many variables that cannot be included in the optimization, such as a terminal belonging to an adjacent cell, it may be desirable to use an orthogonal distribution method that is simple to optimize rather than a non-orthogonal distribution method. Therefore, by using the orthogonal distribution scheme, the base station can estimate the channel of the UL through the reference signal (RS), and can estimate the value of HARQ-ACK from the resources not occupied by the reference signal (RS). When using the reference signal (RS) and the HARQ-ACK bit, a proper balance with the amount of radio resources is required. Since the reference signal RS occupies a radio resource, there are fewer resources for the HARQ-ACK bit. Accordingly, the radio signal for the HARQ-ACK bit may be allocated to the HARQ-ACK bit to improve the detection probability.

Reference signal ( RS Not using) Mapping Way

FIG. 3 is a diagram illustrating a resource element to which an uplink control information (UCI) channel or a UCI channel and a reference signal are allocated. A method of transmitting a UCI channel (method 1) not using the reference signal RS will be described with reference to FIG. 3.

A radio resource to be considered for transmitting the UCI channel may be represented by designating one resource element (RE) 310 as a subcarrier index and a symbol index. The range of the subcarrier index may have a unit of a resource block. On the other hand, the range of the symbol index may have any natural number and length of uplink (UL) subslot. Here, the length of the uplink (UL) subslot may have all values (1, 2, 3, ..., 14) between 1 and 7 or 14, which is the length of the uplink (UL) slot, and the base station is connected to the terminal. The value set by Downlink Control Information (DCI) may be followed among a value set by RRC (Radio Resource Control) or a plurality of values set by RRC.

For example, a UCI channel for allocating 12 subcarriers and two symbols as radio resources may be represented by 24 resource elements 310 and RE shown in FIG. Here, the set of subcarrier indices of the first symbol and the set of subcarrier indices of the second symbol are not necessarily the same, but the first symbol and the second symbol may correspond to symbols adjacent to each other. If the set of subcarrier indices is different from the first symbol and the second symbol, the base station may have a lower error rate since the UCI channel obtains frequency multiplexing. Although FIG. 3 illustrates the first symbol and the second symbol, a symbol set may be considered. A symbol set may consist of one or more symbols, and one symbol set may have the same frequency resource (eg, a PRB index), but different symbol sets may have different frequency resources. In this case, since the UCI channel transmitted by the terminal obtains frequency multiplexing, the base station may have a lower error rate.

As such, since the reference signal RS is not used when the UCI channel is transmitted, the HARQ-ACK bit may be mapped using all resource elements 310 and RE allocated to the symbol. The method of mapping the HARQ-ACK bits may be the same as the method of generating the two-dimensional sequence.

Here, the method of mapping HARQ-ACK bits may be classified into a first method of generating a 2D sequence and a second method of generating a combination of 1D sequences.

In the first method of generating the two-dimensional sequence, the terminal generates the two-dimensional sequence according to the size of the radio resources known to the base station and the terminal in advance and transmits the two-dimensional sequence to the base station, and the base station interprets the first two-dimensional sequence as ACK The second two-dimensional sequence can be interpreted as NACK.

If the terminal generates two HARQ-ACK bits, the base station may interpret the first two-dimensional sequence as ACK and ACK to consider four cases. The base station may interpret the second two-dimensional sequence as ACK and NACK. The base station may interpret the third two-dimensional sequence as NACK and ACK. The base station may interpret the fourth two-dimensional sequence as NACK and NACK.

If the terminal generates n HARQ-ACK bits, 2 ^ n two-dimensional sequences may be generated in consideration of the case of 2 ^ n branches. If the terminal transmits the scheduling request (SR) to the base station, when the terminal transmits the corresponding UCI channel, the base station may detect this and recognize that the terminal makes a scheduling request (positive SR). If the terminal does not transmit the corresponding UCI channel, the base station can not detect this and can recognize that the terminal does not make a scheduling request (negative SR).

As described above, since one terminal uses 2 ^ n two-dimensional sequences, the base station may allocate the two-dimensional sequence in direct proportion to the number of terminals (multiplexing order) that can be accommodated in the same radio resource. In order to generate the two-dimensional sequence, at least the following method can be applied.

For example, the terminal may generate a two-dimensional sequence by generating one two-dimensional base sequence and adjusting a phase of a complex number constituting each sequence. As an example of controlling the declination, cyclic shift may be considered. The base station allocates one base sequence to the terminal, and the terminal may generate one two-dimensional sequence by using a phase modulation suitable for the HARQ-ACK bit combination to the base sequence.

The base station detects a two-dimensional sequence received from the terminal and demodulates the declination, and may determine which HARQ_ACK bit combination is received from which terminal. The base station can sufficiently obtain spreading gain because the two-dimensional sequence is large enough to secure the detection performance of the HARQ-ACK bit, and the modulation of the polarization is performed so that the demodulation of the polarization can be performed without the UL channel information in the base station. Patterns can be defined randomly enough.

The two-dimensional basis sequence may be generated based on at least identification information and cell identification information of the terminal, and the polarization demodulation pattern may be generated based on at least identification information of the terminal.

As an example of the identification information of the terminal, a radio network temporary identifier (RNTI) or a cell radio network temporary identifier (C-RNTI) may be considered. As an example of the cell identification information, a virtual cell identifier or a physical cell identifier may be considered. Alternatively, the polarization modulation may be performed using a slot index or a subslot index in addition to the base station identification information and the terminal identification information.

As another example, the base station may allocate a 2D sequence of 2 ^ n corresponding to the number of combinations of n HARQ-ACK bits to one UE. Each of the two-dimensional sequences may mean a single base sequence or a sequence in which different declination patterns are applied to one base sequence. The terminal may select one of the two-dimensional sequences according to the combination of HARQ-ACK bits and transmit it to the base station. The base station can determine the HARQ-ACK bit combination through the detected two-dimensional sequence.

Subsequently, in the second method of generating the two-dimensional sequence , the terminal may generate a radio resource expressed in two dimensions from the one-dimensional sequence. The terminal may generate the 2D radio resource by a combination of 1D sequences or 2D mapping of 1D sequences. This can be applied when there are one or two HARQ-ACK bits.

Here, a sequence capable of factoring the two-dimensional sequence into the product of the one-dimensional sequence can be used. In this case, the one-dimensional sequence having the subcarrier length K of the radio resource and the one-dimensional sequence having the symbol length L of the radio resource may be considered. This may be represented as in Equation 1 below.

In Equation 1, at least r ₁ mapping to a frequency resource may be differently assigned to the one-dimensional sequence by declination demodulation for each symbol. These one-dimensional sequences can be divided into orthogonal and non-orthogonal sequences, depending on how they are generated.

Examples of orthogonal sequences may include a DFT sequence generated as a row or a column of a Discrete Fourier Transform matrix, a selection sequence generated as a row or a column of an identity matrix, and a Hadamard sequence generated as a row or a column of a Hadamard matrix.

Examples of non-orthogonal sequences may include the Peudo Noise sequence, the Zadoff-Chu sequence, and the Gold sequence. As a method for randomizing UCI channel interference using a non-orthogonal sequence, the declination pattern applied in the first method of generating the two-dimensional sequence described above may be used. In order to generate such a declination pattern, identification information of the terminal or identification information of the base station may be used.

In the second method of generating the two-dimensional sequence described above, the two-dimensional sequence may correspond differently for the purpose of interference management or interference cancellation.

For example, in the case of a radio channel having a large frequency selectivity and a small time selection characteristic, a non-orthogonal sequence may be used as a one-dimensional sequence in the frequency dimension, and an orthogonal sequence may be used as the one-dimensional sequence in the time dimension. . In this way, UCI interchannel interference in frequency resources can be randomized and UCI interchannel interference in time resources can be eliminated.

As another example, in the case of a channel having a large frequency selection characteristic and a time selection characteristic, interference of UCI channels between terminals may be randomized by using non-orthogonal sequences for all of the one-dimensional sequences.

4 is a diagram illustrating an example of mapping two symbols and twelve subcarriers. 5 is a diagram illustrating another example of mapping two symbols and twelve subcarriers.

4 and 5, as an example, a one-dimensional sequence may be generated to map resource elements 310 and RE to two dimensions. The length of this one-dimensional sequence corresponds to the product of the number of symbols and the number of subcarriers. As another example, the one-dimensional sequence may consider orthogonal and non-orthogonal sequences. Examples of orthogonal and non-orthogonal sequences can utilize both of the sequences described above. If a non-orthogonal sequence is used, a declination pattern may be used to randomize interference between UCI channels, and all of the above-described methods may be applied.

As a method of corresponding one-dimensional sequence in two dimensions, as shown in FIG. 4, the terminal maps the resource elements 310 and RE in the order of time resources, and then the resource elements 310 in the order of frequency resources. RE) can be mapped (time first mapping). As another example, as shown in FIG. 5, the terminal may map the resource elements 310 and RE in the order of frequency resources, and then map the resource elements 310 and the RE in the order of time resources. frequency first mapping).

It can correspond to the ascending or descending order of the one-dimensional sequence from the low index of the subcarrier or symbol. The radio resource illustrated in FIGS. 4 and 5 has 12 subcarriers and two symbols. Here, the set of subcarrier indices of the first symbol and the set of subcarrier indices of the second symbol are not necessarily the same, but the first symbol and the second symbol may correspond to symbols adjacent to each other. If the set of subcarrier indices is different from the first symbol and the second symbol, the UCI channel may have a lower error rate through frequency multiplexing. The numbers of the resource elements 310 and RE of FIGS. 4 and 5 may correspond to the indexes of the one-dimensional sequence.

In the case of the UCI channel composed of a symbol set, mapping of resource elements 310 and RE may be performed within one symbol set, and then mapping of resource elements 310 and RE may be performed in another symbol set. The mapping method described above may be applied within one symbol set.

Reference signal Mapping Way

FIG. 6 is a diagram illustrating a method for allocating a resource element RE of a reference signal RS to a specific symbol and a specific subcarrier. FIG. 7 is a diagram illustrating a method for uniformly allocating a resource element RE of a reference signal RS to symbols and subcarriers. 8 is a diagram illustrating a method of allocating a resource element RE of a reference signal RS to all subcarriers of a specific symbol. Hereinafter, a method (transmission method 2) of a UCI channel using a reference signal RS will be described with reference to FIGS. 6 to 8.

The terminal may arrange the resource element 310 (RE) of data and the resource element RE of the reference signal 320 in one symbol. The base station can receive the resource element 320 of the reference signal, estimate the uplink (UL) channel using the reference signal (RS), and can detect the HARQ-ACK bit using this. 6 to 8, the amount of radio resources occupied by the reference signal 320 and the location of radio resources may be determined. 6 to 8 illustrate the size of the subslot as 2. However, the present invention is not limited thereto, and the size of the subslot may be larger than 2.

In FIG. 7, the set of subcarrier indices of the first symbol and the set of subcarrier indices of the second symbol are not necessarily the same. 6 and 8, the set of subcarrier indices of the first symbol and the set of subcarrier indices of the second symbol may be the same.

In FIG. 7, when considering a radio resource such that the first symbol and the second symbol have different subcarrier index sets, the detection performance of the UCI channel may be further improved by using frequency selective characteristics of the radio channel. FIG. 7 illustrates a case in which the subcarrier index interval belonging to the first symbol occupied by the UCI channel, the subcarrier index interval belonging to the second symbol are the same, and the start index of the subcarrier is different from each other. However, the present invention is not limited thereto, and a case in which subcarriers start indexes are the same may be considered according to higher layer configuration.

Here, an example of allocating a UCI channel and a reference signal 320 in a radio resource composed of 24 subcarriers and two symbols is described. An example in which the reference signal 320 is limited to some symbols to map only some subcarriers is described. 6 is shown. If considering a radio channel having a high frequency selection characteristic, when the channel estimation performance of the uplink (UL) is low, as shown in FIG. 8, the reference signal 320 may be mapped on all subcarriers belonging to some symbols.

Considering a radio channel having a high time selection characteristic due to high mobility of the UE, since an uplink (UL) channel estimation is inaccurate, a resource element including the reference signal 320 as shown in FIG. RE) may be mapped not to be limited to a specific symbol or a specific subcarrier in a radio resource. That is, the reference signal 320 may be evenly mapped to the subcarriers of the plurality of symbols. By arranging resource elements RE at the same time and frequency intervals, variance in error of channel estimation can be minimized.

As a method of mapping the reference signal 320 to a radio resource, the resource elements RE occupied by the reference signal 320 may be separately collected and disposed in one symbol or two symbols.

When the reference signal RS is not used, when only one or two HARQ-ACK bits are used, only resource elements RE for allocating HARQ-ACK bits may be collected and mapped separately. However, since the reference signal RS can be used, the HARQ-ACK can be modulated and transmitted into declination information of a sequence. For example, when the HARQ-ACK bit is modulated into a PSK symbol, this may be interpreted as modulation of the declination information.

As an example, the HARQ-ACK bits b0 or b0, b1 may be transmitted using a two-dimensional sequence A. FIG. As another example, each HARQ-ACK bit b0 or b0, b1 may be modulated into a BPSK symbol c or a QPSK symbol d to be multiplied by a two-dimensional sequence. The obtained C · A or d · A can be mapped to radio resources.

When a two-dimensional sequence is derived from the one-dimensional sequences, the BPSK symbol (c) or the QPSK symbol (d) modulated with the HARQ-ACK bit according to the method of mapping to the resource element (RE) can be expressed as the product of the two-dimensional sequence. Can be. This may be expressed as in Equation 2 below.

In Equation 2, r _l _′ mapped to the frequency resource may be differently allocated to the one-dimensional sequence by polarization demodulation for each symbol. Here, K 'may correspond to the number of subcarriers that can be utilized for HARQ-ACK bits, and L' may correspond to the number of symbols that can be utilized for HARQ-ACK bits. S (k ', l') may be mapped to a suitable resource element (RE) according to a predetermined rule defined in the specification for radio resources. In this case, the one-dimensional sequence can be applied in the same manner as described above.

The method of mapping the one-dimensional sequence s to the resource element RE in two dimensions in order to generate the two-dimensional sequence S may be different from that in Equation 2 above.

If the sequence of resource element (RE) mapping starts from the subcarrier, Equation 3 below may be applied.

If the sequence of RE mapping starts with a symbol, Equation 4 below may be applied.

The transmission method of the UCI channel described above should consider harmonization with other physical channels. For example, coexistence between UCI channels, coexistence of a UCI channel and an UL data channel, and coexistence of a UCI channel and a sounding channel should be considered. Here, channels that must coexist may be transmitted by different terminals or may be transmitted by one terminal.

Selection of transmission method according to payload

The UE may generate the UCI channel differently according to the number of bits (payload) transmitted by the UCI and the type of the UCI. The terminal may consider the case of transmitting one bit or two bits. In this case, the type of UCI may include all of HARQ-ACK, channel state information (CSI), and scheduling request (SR). As a specific example, when transmitting a positive SR, or when transmitting a HARQ-ACK for one or two CBg transmitted by the base station, the CRI or RI is set to within 2 bits and CRI or RI in the process of periodic CSI feedback. When transmitting, it corresponds to the case of transmitting HARQ-ACK for message 4 (M4) in the initial access (initial access) process, or a combination of the cases described above. Since different UCI types have different target error rates, even if they have the same UCI channel structure, different UCIs or different transmission powers may be applied to them.

When the UCI channel is set as a single symbol, the UCI channel may include the reference signal RS, and the reference signal RS may be disposed to include the UCI in the remaining resource element RE. When the UCI channel is set to a single symbol, the reference signal RS and the UCI may map resource elements RE using frequency multiplexing (FDM).

If transmitting more than 3 bits, the UCI channel includes a reference signal (RS), it is possible to arrange the reference signal (RS) and include the UCI in the remaining resource element (RE). When the UCI channel is set to a single symbol, the reference signal RS and the UCI may map resource elements RE using frequency multiplexing (FDM).

Scheduling requests (using multiple bits)

9 is a diagram illustrating a UCI channel configured with a reference signal (RS) resource element (RE). FIG. 10 is a diagram illustrating a UCI channel in which a ZP (zero power) reference signal (RS) is additionally set.

9 and 10, a case where the base station is configured to transmit the uplink transmission to the terminal (grant) may be considered. The terminal transmits a scheduling request (SR) to the base station, and receives a scheduling grant from the base station to transmit data in uplink. If the data relates to URLLC (Ultra-reliable Low-Latency Communication), the base station may be configured to the terminal to transmit a scheduling request (SR) using a single symbol UCI channel. In this case, the UCI channel for the scheduling request (SR) may be represented by 1 bit or 2 bits or more.

For example, when a base station sets a scheduling request (SR) resource to a terminal regardless of a service scenario (for example, enhanced mobile broadband (eMBB) or URLLC or mMTC (massive machine type communications), the terminal requests a scheduling request (SR). If the base station performs the uplink eMBB transmission or the uplink URLLC transmission, the base station should be informed if the scheduling request (SR) for uplink URLLC transmission is performed at the base station. In order to do this, the base station sets a separate scheduling request (SR) resource for each service (service-specific) to the terminal, and the UE selects among scheduling request (SR) resources to select a UCI channel. The base station can distinguish the service from the selection of the terminal. Different periods, different transmission time intervals (TTIs), or different parameters (numerology or subcarrier spacing) may be set differently.

On the other hand, the base station may set the scheduling request (SR) to the terminal regardless of the service, and may deliver the service by expressing the scheduling request (SR) in several bits. For example, the terminal may express the scheduling request (SR) for the eMBB uplink, the scheduling request (SR) for the URLLC uplink, and the scheduling request (SR) for the mMTC uplink as information of one bit or two bits or more. have.

As another method, the base station sets a scheduling request (SR) resource for the URLLC service to the terminal, the terminal may generate the scheduling request (SR) by expressing the amount of the uplink buffer in a few bits. For example, the terminal may divide the amount of URLLC traffic into four stages according to size, and generate a scheduling request (SR) by mapping the information into two bits of information.

On the other hand, a UCI channel may be considered that transmits only a scheduling request (SR) and does not transmit another UCI. Since the UCI channel including only the scheduling request SR does not need to separately include the UCI, as shown in FIG. 9, the terminal may transmit only scheduling request (SR) resources configured from the serving base station. In this case, the number of symbols of the UCI channel may be one or more (for example, 1, 2, etc.), and only symbol 1 belonging to this is illustrated in FIG. 9.

In the same subband as the UCI channel transmitting the scheduling request (SR), the sounding reference signal (SRS) may be set in the base station to allow transmission. When the first terminal transmits the UCI channel and the second terminal transmits the sounding reference signal (SRS), it may be difficult for the base station to effectively remove the interference between the UCI channel and the sounding reference signal (SRS). In addition, since an interference signal having a different strength is received for each resource element (RE), the resource element (RE) of the UCI channel colliding with the sounding reference signal (SRS) does not collide with the sounding reference signal (SRS). Resource element (RE) and reception quality are different. To prevent this, a transmission comb (TC) may be introduced into the UCI channel as shown in FIG. 10. The number of symbols included in the UCI channel is one or two, and only one symbol 1 belonging to the UCI channel is shown in FIG. 10, and since only the scheduling request SR is transmitted, the subcarriers except the reference signal RS may not be transmitted. have.

UCI channel carrying one bit or two bits (single symbol)

The structure of a UCI channel using a single symbol is closely related to the sounding reference signal (SRS). Sounding reference signal (SRS) can be set to

TC

2 or 4, the UCI channel is affected by the value of TC. When the sounding reference signal (SRS) is expressed as a complex vector having a constant length of the Zadoff-Chu (ZC) sequence and is mapped to a resource element (RE) on a subcarrier, one or two bits are transmitted in the UCI channel. The case may be considered.

When transmitting 1 bit UCI, the UE may perform frequency multiplexing (FDM) on the subcarrier corresponding to the DM-RS of the UCI channel and the subcarrier corresponding to the spread UCI corresponding to two cases. In order to efficiently coexist with the sounding reference signal (SRS) and to use the Constant Amplitude Zero Auto Correlation (CAZAC) property, the terminal generates "z" which is a sounding reference signal (SRS) of the DM-RS sequence. The sounding reference signal Sw may be applied to the spread code applied to the UCI. The resource element (RE) mapping in this case may be expressed as the following equations.

For example, in the case of DM-RS, it can be expressed as (z (0) 0 0 0 z (1) 0...). If UCI is allocated to an adjacent subcarrier, it can be expressed as (0 w (0) 0 0 0 w (1) ...). The equation of the UCI channel is the sum of these and can be expressed as (z (0) w (0) 0 0 z (1) w (1) ...).

Here, the number of zeros may be determined by TC of the sounding reference signal SRS. In order to transmit 1 bit, an orthogonal cover code (OCC) between subcarriers may be applied. For example, an OCC of length 2 is a Walsh sequence and can be [1, 1] and [1, -1]. For arbitrary lengths, subsequences of the Walsh sequence can be used. As another example, a DFT sequence can be used. This allows the elements in the sequence to use the van der Monde structure of the nth root of unity.

Using this method, a UCI channel for delivering 1 bit can be generated by applying an OCC of length 2 to the base sequence (z (0) w (0) 0 0 z (1) w (1) ...). Can be. For example, if the terminal generates (z (0) w (0) 0 0 z (1) w (1) ...) to deliver '0', to deliver '1', (z (0 ) -w (0) 0 0 z (1) -w (1) ...). Since the base station knows the value in advance in the subcarrier where the value of "z" is located, it can use it as a DM-RS.

Extending the same method, a UCI channel for carrying 2 bits is created by iteratively applying an OCC of length 4 to the base sequence (z (0) w (0) 0 0 z (1) w (1)…). can do. At this time, a Walsh sequence or a DFT sequence may be applied. Applying the Walsh sequence in one way, if the terminal generates (z (0) w (0) 0 0 z (1) w (1)…) to deliver '0', it transmits '1' In order to achieve this, (z (0) w (0) 0 0 -z (1) -w (1) ...) can be generated. And to pass '2', we can generate (z (0) -w (0) 0 0 -z (1) w (1) ...). Then, in order to deliver '3', (z (0) -w (0) 0 0 z (1) -w (1) ...) can be generated.

If another method applies the DFT sequence, if the terminal generates (z (0) w (0) 0 0 z (1) w (1)…) to transmit '0', it transmits '1'. In order to achieve this, (z (0) -j · w (0) 0 0 -z (1) j · w (1) ...) can be generated. Then, in order to deliver '2', (z (0) -w (0) 0 0 z (1) -w (1) ...) can be generated. Then, in order to deliver '3', (z (0) j · w (0) 0 0 −z (1) −j · w (1)…) may be generated. The base station can use this as a DM-RS since the value is known in advance on a subcarrier having a sign of 1 applied to " z "

On the other hand, the resource element (RE) mapping may be expressed as (z (0) 0 w (0) 0 z (1) 0 w (0) ...) using another equation. In this case, since the UCI is located in a subcarrier farther than the DM-RS, an error may be greater in channel estimation and channel interpolation than in the resource element mapping described above. However, when the UCI and the DM-RS are located on the subcarriers at the same interval, there is an advantage of lowering the peak to average power ratio (PAPR).

The method described above uses two sequences, but if UCI and DM-RS are generated in the same sequence, there is no need to distinguish between UCI and DM-RS. Since the subcarriers are located at the same interval, the PAPR performance of the sequence can be maintained as it is equivalent to the operation of mapping a sequence of resource elements (RE).

Coexistence of UCI Channel, Data Channel, and Sounding Reference Signal (SRS)

Referring to FIG. 11, coexistence of a UCI channel and a data channel may be considered. In this case, the resource element RE except for the reference signal 320 in the radio resource that can be used by the UCI channel may be used to transmit HARQ-ACK 350 bits or other UCI. In FIG. 11, the resource element 330 not used in the symbol may be included. When the base station is configured separately, not only the HARQ-ACK 350 bits but also uplink (UL) data 340 of a terminal transmitting the corresponding HARQ-ACK 350 bits or uplink (UL) data 340 of another terminal. ) Can also be assigned.

For example, a first terminal may transmit a UCI channel and a second terminal may transmit a data channel in the same UL subslot. The base station preferably sets the resource element RE used by the first terminal and the resource element RE used by the second terminal differently. Here, the data channel transmitted by the second terminal can be transmitted in an uplink (UL) slot (UL slot), or can be transmitted in an uplink (UL) similar slot (UL-centric slot), or the base station is a second It may be assumed that a UL scheduling is separately performed to a UE to adjust a range of time resources included in the data channel to include at least a symbol in which a UCI channel exists.

In this case, the mapping of the resource element (RE) of the uplink (UL) data 340 of the terminal is all resource elements (RE) in which the reference signal 320 and the HARQ-ACK 350 bits are mapped in the radio resource under consideration. You can use some or all of the parts except.

The radio resource illustrated in FIG. 11 includes a subslot corresponding to one symbol and twelve subcarriers, and a UCI channel and uplink (UL) data 340 composed of a reference signal 320 and HARQ-ACK 350 bits. ) Channels may coexist. The base station allocates a UCI channel and an uplink (UL) data 340 channel to one terminal, but does not need to occupy all resource elements (REs), and as shown in FIG. 11, some resource elements 330 may have power. May not be assigned. In FIG. 11, the first terminal and the second terminal may correspond to each other.

Referring to FIG. 12, a subband of a UCI channel 410 of a first terminal and a subband of a data channel 420 of a second terminal in an uplink (UL) system band of a first subslot. sub-bands may overlap. When the UCI channel is transmitted in a subslot consisting of one or more symbols, the UCI channel may coexist in a frequency band with an uplink (UL) data channel.

The UCI channel 410 transmitted by the first terminal to the base station may be transmitted in the partial band, and the data channel 420 transmitted by the second terminal to the base station may also be transmitted in the partial band. In this case, the partial band of the data channel 420 and the partial band of the UCI channel 410 may partially overlap due to scheduling of the base station. Here, as shown in FIG. 11, when the second terminal encodes the data channel 420, power is not allocated to the resource element RE which is expected to exist in an uplink (UL) channel of another terminal ( Zero Power), the coding rate may be determined by considering only available resource elements (REs), and the resource elements (REs) may be mapped by encoding data. By using such rate matching, the reception performance of the base station can be improved.

The base station may be configured to convert the frequency band of the data channel transmitted by the terminal according to a predetermined pattern every predetermined time unit. In the case of defining such frequency hopping, it is preferable that both the data channel and the UCI channel perform frequency hopping.

Meanwhile, as shown in FIG. 12, the data channel 420 may not perform hopping within the subslot, and the UCI channel 410 may also not perform hopping.

Here, it may be assumed that the data channel 420 is hopped and the UCI channel 410 is not hopped. In this case, in the process of estimating the channel using the DM-RS (DeModulation reference signals) by receiving the data channel 420 at the base station, the channel estimation in the DM-RS and the channel estimation in the data resource element (RE) Can be different. For example, if the DM-RS collides with the UCI channel, but the data resource element (RE) does not collide with the UCI channel 410, the interference hypothesis of the base station for interference is changed, so that an error rate during decoding is increased. Can increase.

In consideration of the opposite case, it may be assumed that the UCI channel 410 is hopped without hoping the data channel 420. In this case, it is preferable to set frequency hopping to the UE transmitting the UCI channel 410, and the time granularity of the frequency hopping can match the UCI channel 410 and the data channel 420. .

Meanwhile, the UL data channel may not transmit data in the resource element RE that transmits the UCI channel or the sounding reference signal SRS. The first terminal transmitting the uplink (UL) data channel and the second terminal transmitting the UCI channel or sounding reference signal (SRS) may be transmitted in the same symbol. In this case, the first terminal may transmit data by using only a resource element (RE) that the uplink (UL) data channel does not transmit from the second terminal. To this end, the first terminal may adjust the code rate. As another example, the first terminal that does not have the capability to adjust the code rate and does not set it in the base station may not allocate data in the corresponding symbol (shortened format). Meanwhile, if the third terminal needs to transmit the UCI channel and the UCI channel or the sounding reference signal (SRS) in the same symbol, the third terminal transmits all according to the configuration of the base station, or partially according to the priority defined in the standard. Can be transmitted.

How to avoid resources allocated to SRS occsion in PUSCH

Referring to FIG. 13, a UCI channel 430 and a sounding reference signal 440 may coexist in an uplink (UL) region. The first terminal may transmit the UCI channel 430, and the second terminal may transmit the sounding reference signal 440. 13 illustrates an example in which the UCI channel 430 and the sounding reference signal 440 are positioned at the last symbol of the slot regardless of the boundary between the downlink (DL) region and the guard period (GP) region. However, the present invention is not limited thereto, and a case in which the UCI channel 430 and the sounding reference signal 440 are generated in the same uplink (UL) symbol may be considered. In this case, the UCI channel 430 and the sounding reference signal 440 may be transmitted on the same subcarrier according to the higher layer configuration of the base station and the DCI.

The sounding reference signal 440 may be transmitted from the terminal to the base station through the configuration from the upper layer of the base station or the configuration of the upper layer and DCI. The sounding reference signal 440 may occupy some regular subcarriers among some consecutive resource blocks (RBs) and radio resources limited to one symbol. The sounding reference signal 440 corresponds to the one-dimensional sequence, and the parameters related to the generation of the one-dimensional sequence may follow the upper layer setting of the base station. The terminal may periodically transmit the sounding reference signal 440 according to the configuration of the base station, or may receive the DCI and transmit the sounding reference signal 440 aperiodically.

Referring to FIG. 14, the resource element 442 and the unused resource element 444 of the sounding reference signal may be disposed in the first symbol. A sounding reference signal (SRS) may be disposed in one subcarrier for every three subcarrier indexes, which corresponds to a case where a transmission Comb is three. As a result, four resource elements RE and a sounding reference signal SRS may correspond.

In order to transmit several sounding reference signals (SRS) in the same radio resource, the base station can suppress the interference between the sounding reference signal (SRS) by setting the subcarrier index set differently, or by generating a one-dimensional sequence differently have. For example, the sounding reference signal (SRS) of the LTE advanced pro may set the bandwidth in multiples of 4 in RB units, and may set the TC value by selecting 2 or 4. In addition, the one-dimensional sequence may be suppressed by using the ZC sequence and cyclic shift.

In order for the base station to configure the UCI channel and the sounding reference signal (SRS) on the same radio resource, the interference suppression method of the UCI channel and the sounding RS should be considered. Since the sounding reference signal SRS described above follows a method of mapping a one-dimensional sequence to the resource element RE according to a predetermined rule, the reference signal RS constituting the sounding reference signal SRS is considered if the UCI channel occupies only one symbol is considered. And UCI can also be generated in a one-dimensional sequence.

If the one-dimensional sequence for generating the sounding reference signal (SRS) and the one-dimensional sequence for generating the UCI channel are set to be the same, it may have a gain in terms of interference suppression compared to otherwise. Therefore, both the reference signal RS of the UCI channel and the UCI of the UCI channel are generated from the one-dimensional sequence of the sounding reference signal SRS, and the base station can set an appropriate generation parameter to the terminal.

Specifically, when a given radio resource is composed of one symbol and N resource blocks (RBs), when TC is set to k, the sounding reference signal (SRS) and the reference signal (RS) of the UCI channel and the UCI channel The UCI may all have a length of 12 × N / k. Unlike the reference signal RS of the UCI channel, the UCI of the UCI channel may be multiplied by a PSK symbol modulated by including a HARQ-ACK bit in a one-dimensional sequence.

15 is a diagram illustrating an example of allocating a UCI channel to a resource block (RB). 16 is a diagram illustrating another example of allocating a UCI channel to a resource block (RB). 15 and 16 illustrate the types of radio resources occupied by the UCI channel when one resource block (RB) is configured in the base station. As shown in FIG. 15, the terminal may configure a symbol with a reference signal 320, an unused resource element 330 (zero power), and a HARQ-ACK 350 bit to transmit to a base station. In addition, as shown in FIG. 16, the terminal may configure a symbol with the reference signal 320 and the HARQ-ACK 350 bits and transmit the symbol to the base station.

One terminal shows the same resource element (RE) mapping as transmitting two sounding resources. The base station may set the bandwidth of the UCI channel according to a resource block (RB) unit that the sounding resource may have. 15 shows a case where TC is 4, and FIG. 16 shows a case where TC is 2. FIG. The TC value may be set to the same value as the TC of the sounding reference signal 320 set by the base station.

The base station can map the UCI of the UCI channel to a longer one-dimensional sequence as needed. In FIG. 14, one sounding resource is allocated to UCI, but several sounding resources may be allocated to UCI as needed.

Referring to FIG. 17, there is shown an example (4 Comb) of a UCI channel limited to two resource blocks (RBs) and allocated two sounding reference signal (SRS) resources to UCI. The terminal may set the first sounding resource 362 having a TC of 4 as a reference signal of the UCI channel, and set the second sounding resource 364 and the third sounding resource 366 as the UCI of the UCI channel. . In case of generating one or two bits of HARQ-ACK, the terminal may generate a one-dimensional sequence having a length twice as long as two sounding resources are used. If more UCI bits are generated, the UE may use two sounding resources to map the encoded UCI bits.

Here, as a method for mapping the resource element (RE), the method of mapping the resource element (RE) in the order of subcarrier index, and the method of mapping the resource element (RE) in the order of subcarrier index for each sounding resource Can be applied.

Referring to FIG. 18, in the case of 4 Combs in two resource blocks RB, a linear mapping of resource element RE mapping is illustrated. In the method of mapping the resource elements (RE) in subcarrier index order, the terminal may map the first sounding resource and the second sounding resource to the first UCI resource 370 without distinguishing each other. In this case, the terminal may map the one-dimensional sequence having a length of 12 to the subcarrier in numerical order and transmit it to the base station. The base station estimates an uplink (UL) channel from the resource element RE of the reference signal 320 and detects an HARQ-ACK bit from the first UCI resource 370.

Referring to FIG. 19, an example of interlacing of resource element RE mapping in the case of 4 Combs in two resource blocks RB is illustrated. In a method of mapping resource elements (REs) in subcarrier index order for each sounding resource, the UE corresponds to the first sounding resource with the first UCI resource 370 and the second sounding resource with the second UCI resource. 380 may be matched. By mapping a six-dimensional one-dimensional sequence to subcarriers in numerical order, the first UCI resource 370 may correspond to the subcarriers in the order of 1, 2, 3, 4, 5, and 6. Thereafter, the second UCI resource 380 may correspond to the subcarriers in the order of 1 ', 2', 3 ', 4', 5 ', and 6'.

As another example, the base station may allocate the second UCI resource 380 first, and then allocate the first UCI resource 370. The terminal may map the second UCI resource 380 first, and then map the first UCI resource 370. Here, a first constant amplitude zero autocorrelation waveform (CAZAC) sequence may be applied to the first UCI resource 370. In addition, the second CAZAC sequence may be applied to the second UCI resource 380. In this case, the same base sequence may be generated, but may be generated by applying independent phase modulation. This can be applied when generating 1 or 2 bits of HARQ-ACK as UCI.

The base station may additionally set the third sounding resource or more sounding resources to the terminal and allocate the UCI channels in order. In this case, the UE may map the UCI channel to the subcarrier by applying the aforementioned method. Since the UE transmits HARQ-ACK bits using a larger number of subcarriers, energy per resource occupied by one subcarrier can be reduced. On the other hand, since the base station obtains a spreading gain or a coding gain, the number of resource elements RE allocated to the UCI channel by the base station can be adjusted according to the frequency selectivity of the wireless channel and the loss of the propagation path. .

20 is a diagram illustrating a first embodiment in which a UCI channel is configured with 48 subcarriers. FIG. 21 is a diagram illustrating a second embodiment in which a UCI channel is configured with 48 subcarriers. FIG. 22 is a diagram illustrating a third embodiment in which a UCI channel is configured with 48 subcarriers. FIG. 23 is a diagram illustrating a fourth embodiment in which a UCI channel is configured with 48 subcarriers.

20 to 23, the base station may set the ratio of the reference signal (RS) and the ratio of UCI resources to the terminal using higher layer signaling. The base station may set the ratio of the reference signal (RS) and the ratio of UCI resources to the terminal according to the number of bits (1 or 2 bits or more) of the UCI channel. In addition, according to the path loss of the uplink of the terminal and the base station, the base station may set the ratio of the reference signal (RS) and the ratio of UCI resources to the terminal.

The base station knows the number of bits of the UCI channel of the terminal in advance, and assuming channel reciprocity separately, the base station uses the estimated value of the downlink (DL) path attenuation reported from the terminal to determine the uplink (UL). You can infer path attenuation. In addition, the base station can directly infer the path attenuation of the uplink through the sounding reference signal (SRS). Resource element (RE) mapping of the UCI channel to this can be determined by the bandwidth of the TC and UCI channel. As shown in FIGS. 20 to 23, the UCI channel may be configured to have 48 subcarriers.

For example, FIG. 20 sets the TC to 4 when the ratio of the reference signal 320 and the UCI resource 370 is 1: 1 and is limited to four resource blocks RB, and the length of the reference signal 320 is shown. Is set to 12, and the length of the UCI resource 370 is set to 12.

As another example, FIG. 21 is limited to four resource blocks (RBs) and TC is set to 2 when the ratio of the reference signal 320 and the UCI resource 370 is 1: 1, and the reference signal 320 and It shows that the lengths of all the UCI resources 370 are set to 24. FIG.

As another example, FIG. 22 is limited to four resource blocks (RBs), and TC is set to 4 when the ratio of the reference signal 320 and the UCI resource 370 is 1: 3, and the reference signal 320 is used. Indicates that the length of U is set to 12 and the length of the UCI resource 370 is set to 36. FIG.

As another example, FIG. 23 is limited to four resource blocks (RBs), and TC is set to 2 when the ratio of the reference signal 320 and the UCI resource 370 is 1: 2, and the reference signal 320 It is shown that the length of is set to 12, the length of the UCI resource 370 is set to 24, and the length of the unused resource 330 (zero power) is set to 12.

In FIG. 20 and FIG. 23, the base station may map the UCI by using the remaining subcarriers without using some of the subcarriers belonging to the bandwidth of the UCI channel in consideration of coexistence with sounding resources or an uplink (UL) data channel. have. In addition, the resource element (RE) mapping corresponding to the sequence of subcarriers in FIG. 20 to FIG. 23 includes the resource element (RE) mapping method described with reference to FIG. 18 or the resource element (RE) mapping method described with reference to FIG. 19. Applicable

Here, the UCI resource may be used differently according to the number of bits of the UCI channel. If the UCI resource transmits 1 or 2 bits, the UE may transmit the UCI using one CAZAC sequence. On the other hand, if the UCI resource transmits tens of bits, the UE may map the resource element (RE) to the UCI channel UCI encoded through the channel error (forward error correction coding). In this case, the coding rate may be adjusted in consideration of coexistence with a sounding resource or an uplink (UL) data channel, and some of the resource elements (RE) belonging to the bandwidth and the symbol of the UCI channel may not be used.

The base station may set the relative ratio of the transmission power between the reference signal (RS) of the UCI channel and the UCI to higher layer signaling. If necessary, the base station may instruct the terminal to increase or decrease the magnitude of the transmission power through the DCI. To this end, the base station transmits a power control command to a single terminal or a plurality of terminals using a common control search space or a cell-specific search space or a group common control resource set belonging to a control channel. Can be sent to.

Coexistence of sounding reference signal (SRS) resources and UCI channel resources

Referring to FIG. 24, as another method in which a sounding reference signal (SRS) and a UCI channel coexist, the sounding reference signal (SRS) and the UCI channel do not coexist in a single physical resource block (PRB). . A resource region in which sounding reference signals (SRSs) coexist may be referred to as a SRS resource pool, and a resource region in which UCI channels (eg, PUCCH) coexist may be referred to as a UCI channel resource pool. . The UE may transmit the SRS resource pool and the UCI channel resource pool by frequency modulation (FDM).

In FIG. 24, a symbol may be located at an arbitrary position in an uplink (UL) slot, or may be located at a location determined by RRC (Radio Resource Control) signaling at a base station. The bandwidths of the SRS subbands may be different from each other, and the bandwidths of the subbands of the UCI channel may be different from each other.

The sounding reference signal (SRS) resource pool may consist of several sub-bands. In FIG. 24, a sounding reference signal (SRS) resource pool is configured with three subbands as an example. In one sounding reference signal (SRS) subband, the terminal (s) is equal to or wider than the minimum bandwidth of the sounding reference signal (SRS) at the base station so that the terminal (s) can transmit the sounding reference signal (SRS). ) Can be set to RRC.

The bandwidth of the sounding reference signal (SRS) transmitted by the terminal may be set to the RRC from the base station. In one sounding reference signal (SRS) subband, sounding reference signals (SRS) transmitted from multiple terminals may be transmitted to FDM or CDM.

The UCI channel resource pool may consist of several subbands. In FIG. 24, the UCI channel resource pool is composed of three subbands. In one UCI channel subband, the base station may set the RRC to the terminal (s) to be equal to or wider than the minimum bandwidth of the UCI channel so that the terminal (s) can transmit the UCI channel. The bandwidth of the UCI channel transmitted by the UE is set by the RRC signaling from the base station, and a UCI channel having a specific format can be set by the RRC signaling according to the UCI type and the amount of UCI. The specific UCI channel format may have a bandwidth determined by the TS or may configure a bandwidth to the UE using RRC signaling at the base station. Alternatively, the base station may inform the terminal of the bandwidth of the UCI channel by using the RRC signaling and the downlink control channel.

The base station may transmit the format of the UCI channel and the frequency resource and time resource region used by each terminal to the terminal using RRC signaling or DCI, or RRC signaling and DCI. Therefore, in one UCI channel subband, UCI channels transmitted from multiple terminals may be transmitted through FDM or CDM.

FIG. 25 illustrates a second embodiment of configuring a sounding reference signal (SRS) resource pool and a UCI channel resource pool. FIG. 26 is a diagram illustrating a third embodiment of configuring a sounding reference signal (SRS) resource pool and a UCI channel resource pool. The base station may allocate the SRS resource pool and the UCI channel resource pool in two or more symbols. In this case, the form in which the SRS resource pool and the UCI channel resource pool coexist may change. This resource pool allocation method is illustrated in FIGS. 25 and 26. FIG. 25 illustrates a method of allocating the same resource pools from the first symbol and the second symbol. FIG. 26 illustrates a method of allocating different resource pools from the first symbol and the second symbol. In this case, the first symbol and the second symbol do not necessarily need to be located consecutively in time.

Referring to FIG. 25, two symbols may be maintained without changing the frequency domain of the resource pool. A case in which the sounding reference signal SRS is repeatedly transmitted on the same resource (frequency and code) for two symbols may be allowed. In addition, the UCI channel may allow the case of repeatedly transmitting the same resource (frequency and code) for two symbols.

The UE repeatedly transmits the same resource using the same resource in the same subband, thereby obtaining a frequency diversity gain. On the other hand, by repeatedly transmitting the terminal, the base station can estimate the channel more accurately, and has an advantage of accommodating a larger number of terminals.

As an example, the terminal may perform uplink management by using the sounding reference signal (SRS) in two or more symbols. The UE maintains the same preprocessing vector (precoding) in the same frequency resource in the two symbols, and the base station can find the most advantageous receive postprocessing vector (receive beamforming) by maintaining the uplink in the process of receiving it.

As another example, the UE may use the same frequency resource while transmitting a UCI channel using two symbols. In this case, the base station may allocate a code resource to the terminal and apply it to the reference signal (RS) of the UCI channel. In this case, when receiving a plurality of UCI channels in the same resource, the received several UCI channels can be divided into CDM (Code Division Multiplex).

In case of using different frequency resources in two symbols, the sounding reference signal (SRS) subbands are used differently in the first symbol and the second symbol, or the sounding reference signal even in the same sounding reference signal (SRS) subband. The frequency resource used by the (SRS) may be used differently. Similarly, UCI channel subbands may be used differently in the first and second symbols, or frequency resources may be used differently in the same UCI channel subbands. If the partial band is used differently for each symbol, frequency multiplexing gain can be obtained.

However, since the sounding reference signal (SRS) partial band is maintained for two symbols, it is necessary to use more time to estimate the channel state information (CSI) at the base station using the sounding reference signal (SRS). The UE may transmit the sounding reference signal (SRS) in the entire band only by using the sounding reference signal (SRS) partial band that has not been previously allocated using other symbols.

Referring to FIG. 26, an SRS resource pool and a UCI channel resource pool may be arranged in a first symbol and an SRS resource pool and a UCI channel resource pool may be allocated in a second symbol. Here, the frequency resource position of the resource pool can be changed for each symbol, and the terminal cannot perform repeated transmission at the same frequency. Accordingly, the terminal may be difficult to manage the uplink and may not repeatedly transmit the UCI channel using two symbols. On the other hand, the terminal can obtain a frequency multiplexing gain. In addition, using the sounding reference signal (SRS) only the partial band has the advantage of reducing the time to obtain the CSI for the entire band in the base station.

Setting the Sounding Reference Signal (SRS) Occurrence

The terminal and the serving base station may perform uplink (UL) management using the sounding reference signal (SRS). Receive strength for multiple UL (eg, K ≥ 2) so that the uplink (UL) of the UE and the serving base station are not interrupted even in an environment with high blockage probability Can be managed by the serving base station. To this end, one UL may be managed corresponding to one sounding reference signal SRS. The serving base station may set the K sounding reference signal (SRS) resources to the terminal, respectively, the terminal in the form of a list (list) having K sounding reference signal (SRS) resources in one information unit (Information Element) RRC (Radio Resource Controller) can be set.

In this case, each sounding reference signal (SRS) resource set by the terminal operates independently, so that the period and slot offset of the sounding reference signal (SRS), and in the case of generating a bandwidth or a sequence less than K or K It may correspond to a number. The serving base station may compare the K uplink (UL) channel information obtained from the K sounding reference signals (SRS).

However, when the K sounding reference signals (SRS) occupy different bands from other periods, there is a disadvantage that it is difficult to compare in terms of uplink (UL) management, but the present invention proposes a method to compensate for these disadvantages.

If the terminal supports a wide UL bandwidth and is located at the coverage boundary of the serving base station, the serving base station may set the sounding reference signal (SRS) to the terminal in narrow band in consideration of power consumption of the terminal. In this case, the quality of the two ULs measured by the sounding reference signal SRS received in each of the two arbitrary subbands cannot be compared equally. The reason is that the terminal transmits the sounding reference signal (SRS) only in one subband when the terminal transmits the sounding reference signal (SRS) in a narrow band, so that the sounding reference signal depends on a period set by the base station. This is because the time difference between two specific subbands in which the (SRS) is transmitted is large.

In addition, the quality of two ULs obtained from two sounding reference signals (SRS) measured at different times may not be equally comparable because they may exceed the coherence time of the channel.

In this case, the K sounding reference signal (SRS) resources may be configured to have similar or identical time and frequency resources. For example, a time section in which sounding reference signal (SRS) resources are sequentially located may be set, and a frequency section including sounding reference signal (SRS) resources may be set.

In the same way, when setting the K sounding reference signal (SRS) resources in the serving base station to the terminal, it can be implemented to occur within a specific time interval and frequency interval. In this case, in order to reduce the amount of RRC signals, configuration variables including at least a common period, a slot offset, a bandwidth, and the number of antenna ports are set to the terminal and collectively applied to the K sounding reference signals (SRS). Can be. A configuration variable corresponding to all or part of the K sounding reference signals SRS may be set to the terminal.

Referring to FIG. 27, resources capable of potentially transmitting sounding reference signals (SRSs) may be defined as sounding reference signal (SRS) bursts or occasions. The serving base station may transmit the aperiodic trigger to the terminal through the downlink (DL) control channel, so that the terminal transmits a sounding reference signal (SRS). In this case, since the sounding reference signal (SRS) may not be transmitted within the sounding reference signal (SRS) occasion, the terminal may transmit a sounding set of resources capable of transmitting the sounding reference signal (SRS). It may be defined as a reference signal (SRS) occasion or a sounding resource pool. Depending on the setting of the serving base station, this sounding reference signal (SRS) occasion may be utilized as a pool of resources shared by the terminals.

For example, the base station may set a set of sounding reference signal (SRS) resources, a resource pool, or a sounding reference signal (SRS) occasion to the terminal as RRC. In addition, the relative position may be set to the RRC again to correspond to each sounding reference signal (SRS) resource. The period and the slot offset or the duration of the sounding reference signal (SRS) occasion may be set to the terminal as RRC. The sounding reference signal SRS consisting of K pieces may additionally set a relative symbol offset to the terminal within the sounding reference signal SRS occasion. When the length of the sounding reference signal (SRS) occasion corresponds to one slot, the base station may not set the length of the sounding reference signal (SRS) occasion to the terminal. In this case, the sounding reference signal (SRS) occasion may be set for each serving base station (cell-specific), and each sounding reference signal (SRS) resource may be configured for each UE (UE-specific).

The serving base station may perform RRM (Radio Resource Management) measurement such as RSRP (Reference Signals Received Power) using a sounding reference signal (SRS) belonging to a sounding reference signal (SRS) occasion. When the serving base station performs RRM measurement, it is preferable that the sounding reference signal (SRS) does not perform frequency hopping, and the serving base station may not set frequency hopping to the terminal.

In FIG. 27, K = 4 sounding reference signal (SRS) resources correspond to 4 uplinks (ULs), respectively, and the terminal may transmit sounding reference signals (SRS) in 4 consecutive symbols. Here, the period corresponds to a T slot and may or may not perform frequency hopping. In this case, four sounding reference signal (SRS) resources have the same bandwidth and are transmitted in the same slot. In addition, the duration of the sounding reference signal (SRS) occasion is illustrated as one slot. The terminal transmits a sounding reference signal (SRS) k (k = 1, 2, 3, 4) in symbol k, which may be transmitted in a symbol index set by the serving base station in slot n. Each sounding reference signal SRS need not be the same antenna port of the terminal and may not be the same sounding resource.

The serving base station may trigger the sounding reference signal (SRS) occasion to the terminal using the DCI, or may be configured using the RRC to periodically transmit the sounding excitation signal (SRS) occasion to the terminal.

The sounding reference signal (SRS) occasion may occupy a large amount of resource elements RE. Therefore, when the serving base station instructs many terminals to perform uplink management, the amount of resource elements (REs) can be reduced in consideration of multiplexing of sounding reference signal (SRS) occasions transmitted by each terminal. have. To this end, the serving base station may set the Tc of the sounding reference signals (SRS) belonging to the sounding reference signal (SRS) occasion and a declination modulation pattern of the sequence for each terminal. In this case, the serving base station may be configured to multiplex the sounding reference signals (SRS) within the same resource block (PRB). In addition, the serving base station may set a slot and a partial band in which sounding reference signal (SRS) occasions occur to a common value. In such a configuration of the serving base station, more resources of the uplink (UL) can be allocated to the uplink (UL) data channel.

Sounding Reference signal ( SRS ) Vacation and Dynamic reuse of UL data channel

When there is a first terminal for transmitting a sounding reference signal (SRS) resource or a sounding reference signal (SRS) occasion and a second terminal for transmitting an uplink (UL) data channel, the serving base station is the first terminal. Resources may be allocated to the first terminal and the second terminal so that the second terminal and the second terminal use different resources. However, when frequency hopping is performed while transmitting a sounding reference signal (SRS) resource or a sounding reference signal (SRS) occasion, the frequency hopping pattern is a shape in which uplink (UL) data channel is frequency hopping. Can be different from.

Here, the shape of frequency hopping may include a boundary of time for performing frequency hopping and a bandwidth of frequency hopping. In the case of the sounding reference signal (SRS) occasion, since it is located in the middle of the slot, it should be able to be multiplexed with the UL data channel. If the shape of frequency hopping is the same as the sounding reference signal (SRS) resources and the uplink (UL) data channel, the sounding reference signal (SRS) resource (s) and the second terminal from the serving base station to the first terminal. Frequency resources may not collide even if the UL data channel is independently allocated to the UE. However, in general, since the shape of frequency hopping is different, a serving base station needs a method of avoiding such collision.

A frequency resource of an uplink (UL) data channel may be finely scheduled to avoid transmission of a sounding reference signal (SRS) or a sounding reference signal (SRS) at the serving base station. However, when the time unit of the UL data channel and the time unit of the sounding reference signal (SRS) resources are different, the collision cannot be avoided by the scheduling method. This may be commonly applied to sounding reference signal (SRS) occasions that do not perform frequency hopping or sounding reference signal (SRS) occasions that perform frequency hopping.

The serving base station needs to distinguish whether or not the first terminal actually transmits the sounding reference signal (SRS) in the sounding reference signal (SRS) occasion transmitted by the first terminal. The sounding reference signal (SRS) occasion refers to a resource to which the first terminal can potentially transmit the sounding reference signal (SRS). Therefore, when the first terminal transmits the sounding reference signal SRS based on the trigger of the serving base station, the sounding reference signal SRS may not transmit the sounding reference signal SRS. The serving base station may not give any indication to the first terminal. In this case, the serving base station may allocate resources corresponding to a sounding reference signal (SRS) occasion as an uplink (UL) data channel of the second terminal. To this end, the serving base station may allocate a resource including a sounding reference signal (SRS) occasion as a UL data channel in a downlink (DL) control channel scheduled to the second terminal. In addition, the serving base station may inform the second terminal of information on whether or not the first terminal actually uses a resource corresponding to a sounding reference signal (SRS) occasion.

As an example, the serving base station includes a bitmap in a downlink (DL) control channel to a second terminal, so that a mapping and coding rate of an uplink (UL) data channel for a specific sounding reference signal (SRS) occasion You can direct the adjustment. Each bit of the bitmap may correspond to a sounding reference signal (SRS) occasion.

FIG. 28 is a diagram illustrating a first embodiment of multiplexing an uplink (UL) data channel and a sounding reference signal (SRS) occasion. FIG. 29 is a diagram illustrating a second embodiment of multiplexing an uplink (UL) data channel and a sounding reference signal (SRS) occasion. 30 illustrates a third embodiment of multiplexing an uplink (UL) data channel and a sounding reference signal (SRS) occasion.

Referring to FIGS. 28 to 29, a time domain in which an uplink (UL) data channel does not do frequency hopping or does not hop even when frequency hopping may be considered. One or more sounding reference signal (SRS) occasions may be set in the serving base station. When frequency hopping is performed even with one sounding reference signal (SRS) occasion, it can be interpreted that the shape of the resource is changed from the sounding reference signal (SRS) ocean 1 to the sounding reference signal (SRS) ocean 2. . Therefore, by using two or more time and frequency resources, the sounding reference signal (SRS) ocean 1 and the sounding reference signal (SRS) ocean 2 can be arranged in the slot (or mini slot).

FIG. 28 illustrates a method for allocating all resources of a sounding reference signal (SRS) occasion to an uplink (UL) data channel. In addition, FIG. 29 illustrates a method in which all resources of the sounding reference signal (SRS) occasion are not allocated to the UL data channel. As shown in FIG. 28 and FIG. 29, the UE maps an uplink (UL) data channel to a resource element (RE) and adjusts the coding rate of uplink (UL) data according to the instruction of the serving base station. )can do.

If, even if the second terminal does not transmit the sounding reference signal (SRS), even if the resource allocation information for the sounding reference signal (SRS) Ocean 1 and the sounding reference signal (SRS) Ocean 2, FIG. 28 As shown in FIG. 29, an uplink (UL) data channel may be mapped.

On the other hand, whether the second terminal does not know the resource allocation information for the sounding reference signal (SRS) Ocean 1, or whether the sounding reference signal (SRS) Ocean 1 and the sounding reference signal (SRS) Ocean 2 reused? In another case, as shown in FIG. 30, an uplink (UL) data channel may be mapped.

In FIG. 30, a portion of resources of a sounding reference signal (SRS) occasion is allocated to an uplink (UL) data channel, and a portion of resources of a remaining sounding reference signal (SRS) occasion is allocated to an uplink (UL) data channel. The method is not assigned to. 30 illustrates that sounding reference signal (SRS) ocean 1 is allocated to an uplink (UL) data channel and sounding reference signal (SRS) ocean 2 is not allocated to an uplink (UL) data channel. It is shown.

시간 자원의 할당Allocation of time resources

The base station may instruct the terminal of the location of the radio resource for transmitting the UCI channel using higher layer signaling or higher layer signaling and the downlink control channel. In addition, the base station may instruct the terminal of the location of the radio resource for transmitting the UCI channel using the DCI.

The time resource position of a radio resource may consist of one or more uplink (UL) subslots, and the subslot includes a symbol located at the end of an uplink (UL) slot, or an uplink (UL) ) May be located in the middle of the slot. When used for preprocessing based wireless communication in a high frequency band (eg, 6 GHz or more), the subslot may be configured and operated as one symbol. Meanwhile, even in a low frequency band (eg, less than 6 GHz), the subslot may be set to only one symbol, and may mean some symbols located at the end of the slot. As shown in FIG. 13, the present invention can be applied to both a DL-centric slot or an UL slot, thereby distinguishing a frequency division duplex (FDD) from a time division duplex (TDD). You can apply without.

The base station may measure the uplink (UL) reception power of the terminal to control the terminal to have an appropriate transmission power. In addition, the base station may indicate the number of subslots for transmitting the UCI channel by using a higher layer configuration or a higher layer configuration and the downlink control channel. When considering a burst (UCI channel burst or UCI channel occasion) transmission in which a base station transmits a UCI channel several times, the size of a time resource occupied by one burst transmission may correspond to a subslot. In addition, multiple burst transmissions may correspond to aggregation of subslots.

In the case of tying uplink (UL) subslots, it is not necessary to align the boundaries of UL slots or similar UL slots. Therefore, the case where the transmission of the UCI channel is terminated in the subslot located in the middle of the next slot beyond the corresponding slot can be allowed. In this case, since the base station obtains sufficient reception power from the terminal, it is possible to save transmission energy of the terminal, to utilize uplink (UL) radio resources for other purposes, and to suppress unnecessary uplink (UL) interference.

Referring to FIG. 31, one slot may be configured with several subslots, and FIG. 31 illustrates one slot configured with four subslots. The length of each subslot may be indicated by the base station to higher layer signaling or higher layer signaling and downlink control channel for each terminal. The first UCI channel located in the first slot does not have a separate subslot aggregation, and a method of transmitting a UCI channel (method 1) that does not use the reference signal RS described above with reference to FIGS. 3 to 5 is applied. can do. In addition, the transmission method (method 2) of the UCI channel using the reference signal (RS) described above with reference to Figures 6 to 8 can be applied.

The base station may configure some or all subslots belonging to only the second slot to configure a second UCI channel. As an example for utilizing the second UCI channel, the UE uses the UCI channel transmission method (method 1) and the reference signal RS that do not use the reference signal RS to generate the second UCI channel. UCI channel transmission method (method 2) can be applied. In addition, the terminal may transmit a large amount of UCI not more than 1 bit or 2 bits to the UCI channel by using channel coding.

As another example for utilizing the second UCI channel, when the UE performs UCI channel burst transmission, the UE may repeatedly transmit as many as the number of subslots, and the base station may improve reception quality. The aggregation of these subslots may end at the border of the slot, but the aggregation of subslots does not necessarily have to end at the border of the slot.

The third UCI channel consists of three subslots, but subslots belonging to both the second slot and the third slot may be used. Since the base station no longer needs to instruct the UE to transmit the UCI channel after obtaining the sufficient reception quality, it may not include the last subslot of the third slot.

주파수 자원의 할당Allocation of frequency resources

The base station may instruct the terminal of the frequency resource location of the radio resource. The UE may indicate the frequency resource location of the radio resource by using the higher layer signaling or the higher layer signaling of the base station and the downlink control channel. The frequency resource location may be explicitly indicated by the downlink control channel, or the frequency resource location may be derived using a parameter included in the downlink control channel.

For example, in the case of a UCI channel using only one symbol, since only one symbol is used, the UCI channel does not perform frequency hopping. In addition, the base station may set the frequency resource position used by the UCI channel to the edge of the uplink (UL) spectrum. When the base station allocates an uplink (UL) data channel to the terminals, the complexity of scheduling can be reduced. In particular, in an uplink (UL) data channel using DFT-s-OFDM, scheduling of adjacent bands as an uplink (UL) data channel may be advantageous to lower PAPR. Therefore, in order to allocate a high transmission amount to the terminal, a wide bandwidth must be scheduled adjacently. On the other hand, the UL data channel using CP-OFDM does not further increase the PAPR even if the adjacent band is not scheduled. Accordingly, even if a plurality of narrow bandwidths are scheduled without adjacently scheduling a wide bandwidth, a high transmission amount can be allocated to the terminal. Here, when scheduling a wide bandwidth, the base station can improve the reception quality by more effectively using the DM-RS of the uplink (UL) data channel.

Even when the base station transmits a UCI channel in a single symbol, only when a sufficient reception quality is obtained, transmission of the UCI channel composed of a single symbol may be allowed to a UE in a good position in uplink (UL) coverage. Since the uplink (UL) bandwidths set by the terminals may be different from each other, the base station may set the edges of the uplink (UL) bandwidths recognized by the terminals. This principle can be applied to the transmission of other general UL channels as well as the UCI channel using only one symbol.

32 is a diagram illustrating an example of a subband for a UCI channel in an UL bandwidth configured for a terminal. 33 is a diagram illustrating another example of a subband for a UCI channel in an UL bandwidth configured for a terminal. 32 and 33 illustrate only terminals that use only one symbol and receive different uplink (UL) bandwidths. Here, a band narrower than a UL system bandwidth of an uplink (UL) system operated by a base station may be set to UEs (UE-specific UL bandwidth).

Referring to FIG. 32, although uplink (UL) bandwidths of terminals are different from each other, the same edges may be shared as the lowest physical resource block (PRB) index. In FIG. 32, a hatched portion means a sub-band capable of transmitting a UCI channel. In the same subband region, UEs may schedule or configure UCI channels to be multiplexed and other UL channels not to use the corresponding frequency region. That is, the uplink (UL) may be scheduled at the base station or configured for the terminals at the base station so that another uplink (UL) channel may not be multiplexed with a partial band of the UCI channel.

Referring to FIG. 33, while the bandwidths of the terminals are different from each other, the same center frequency may be shared with each other. The portion indicated by hatched in FIG. 33 means a partial band capable of transmitting such a UCI channel. In this same subband, the UEs may coexist (multiplexing) UCI channels. In addition, uplink (UL) data channels may coexist. The base station may set different uplink (UL) bandwidth differently according to the capability of the terminal. Thus, if the center frequency is shared from the perspective of a base station (or serving cell), some UEs may have a UCI channel subband at the edge of the system band, while others may have a UCI channel subband at the middle of the system band. have.

Here, the UCI channel subband may mean a frequency domain in which one or more terminals transmit the UCI channel. The base station may set one or more formats to the terminal and apply different formats according to the type and size of the UCI to be transmitted by the terminal. The UE may use the same partial band according to the format of the UCI channel, or may use the partial band differently according to the format of the UCI channel. In this case, the terminal may transmit the UCI channel format 1 in partial band 1 and may not transmit in partial band 2.

The base station may not only receive the UCI channel in the UCI channel subband, but may also receive an uplink (UL) data channel according to the configuration or scheduling of the base station, or may receive a sounding reference signal (SRS).

As illustrated in FIG. 32, frequency resources used by terminals in the base station may be allocated from edges, and the remaining frequency resources may be allocated a wideband physical channel and a physical signal. For example, a terminal (eg, a first terminal) that transmits an uplink (UL) data channel in a DFT-s-OFDM waveform may transmit a high transmission amount using a wide bandwidth. Even when transmitting a sounding reference signal (SRS), the terminal centered close to the base station transmits the sounding reference signal (SRS) over a wide band, so that the base station can obtain UL CSI (Channel State Information) in a short time. have. In addition, the base station may be configured to transmit only UCI channels in the UCI channel subband. Therefore, there is no need to consider multiplexing the UCI channel and the UL data channel or multiplexing the UCI channel and the sounding reference signal (SRS).

On the other hand, as shown in Figure 33, the base station can match the center frequency of the terminals. Here, the UCI channel subband is located in the middle of the frequency to some terminals (eg, the first terminal), but may be located at the edge of the frequency to the other terminals (eg, the third terminal). In this case, since the UCI channel can be transmitted in the middle region of the UCI channel subband, multiplexing of an uplink (UL) data channel and a UCI channel or multiplexing of a UCI channel and a sounding reference signal (SRS) may be considered. In addition, the UL scheduler may instruct the UE to use CP-OFDM rather than the uplink (UL) data channel to use DFT-s-OFDM, thereby improving PAPR (Peak-to-Average Power Ratio). Can be.

34 is a diagram illustrating a method of assigning UL bands that match edges of frequencies. 35 is a diagram illustrating a method for allocating an UL band for matching the center of frequency.

34 and 35, a UCI channel using two or more symbols may be considered. For example, when using two symbols, in order to obtain a frequency multiplexing gain, the terminal may not perform frequency hopping using multiple clusters, or the terminal may perform frequency hopping while using a single cluster. When the base station configures different bandwidths for the terminals, the case of performing frequency hopping may be considered. In this case, it is preferable not to locate the UCI channel transmitted by the terminal only at the edge of the uplink (UL) frequency.

Since the base station cannot multiplex the UCI channels that hop at different bandwidths, the UCI channel may use two or more UL frequency bands in the case of assuming frequency hopping. Accordingly, in this case, the base station may multiplex uplink (UL) data channels and UCI channels, or configure the base station to transmit UCI channels by separately assigning predetermined frequency resources to the terminals. For example, the base station may set a frequency resource (for example, a frequency resource of the UCI channel) to the terminal using higher layer signaling, and downlink the information indicating at least one of the frequency resources set by the higher layer signaling. It can be transmitted to the terminal through the control channel.

In order to multiplex only UCI channels, a case in which the base station separately configures partial bands may be considered. In order to set common frequency resources to the terminals, as shown in FIGS. 34 and 35, the base station may set frequency hopping of the UCI channel with the narrowest bandwidth. Here, as shown in FIG. 34, the base station may allocate uplink (UL) bandwidth by matching frequency edges. In addition, as shown in FIG. 35, the base station may allocate uplink (UL) bandwidth by matching frequency centers.

When the terminal performs frequency hopping of the UCI channel, the frequency resource of the UCI channel may be designated as follows. The UE may transmit a UCI channel within an active UL BWP. To this end, the serving base station may inform the terminal of the active UL band portion to which the UCI channel belongs. The active UL band portion may be one of a plurality of UL band portions that the serving base station sets to higher layer signaling (eg, RRC signaling) to the terminal. The configuration information of the UL band portion may be transmitted through higher layer signaling, and the configuration information of the UL band portion may include information indicating a set of frequency resources of the UCI channel (or a partial band of the UCI channel). Accordingly, the terminal may check the frequency resource of the UCI channel based on the configuration information of the UL subband obtained through higher layer signaling.

UCI channel allocation information (eg, UL band) for transmitting HARQ response (eg, HARQ-ACK bits) for the downlink data channel as well as allocation information of the downlink data channel through the downlink control channel Part) may also be transmitted. To this end, the serving base station may inform the terminal comprehensively of the DL band portion and the UL band portion. Alternatively, the serving base station may independently inform the terminal of each of the DL band portion and the UL band portion. In this case, the terminal may identify the active UL band portion based on the UL band portion indicated by the serving base station, and based on the identified information, the frequency resource of the UCI channel actually used among the set of frequency resources available for the UCI channel. Can be specified.

However, allocation information of the active UL band portion may not always be signaled through the downlink control channel through which allocation information of the downlink data channel is transmitted. For example, only the allocation information of the active DL band portion may be signaled through the downlink control channel without the allocation information of the active UL band portion. In this case, the terminal may estimate the UL band portion used for the transmission of the UCI channel by reusing the allocation information of the last received active UL band portion. The terminal may perform frequency hopping using the frequency resource of the UCI channel defined in the UL band portion.

However, in the manner described above, the active UL band portion may not be dynamically adjusted. Since the capabilities of the terminals are different and the number of bits available for indicating the active UL band portion is limited, there may be a case where the resolution is insufficient to indicate the same frequency resources. In this case, the frequency resource of the UCI channel may be indicated by other information and signaling instead of allocation information of the active UL band portion. The terminal may obtain the information of the first frequency resource and the information of the second frequency resource of the UCI channel from the serving base station for frequency hopping.

For example, the serving base station may be configured through higher layer signaling so that the UE transmits the UCI channel based on the frequency hopping scheme, and information of the frequency resource used for frequency hopping of the UCI channel (eg, the first frequency). Information of a resource, information of a second frequency resource, etc.) may be informed to the terminal through higher layer signaling. The range of the first frequency resource may be the same as the range of the second frequency resource. The serving base station may inform the user equipment of the set of frequency resources for the UCI channel through higher layer signaling, and information on at least one frequency resource belonging to the set of frequency resources indicated by the higher layer signaling (for example, the UCI channel). Frequency resource information used for transmission) may be informed to the terminal through a downlink control channel. Here, the information of the second frequency resource may be transmitted separately from the information of the first frequency resource. For example, the serving base station may transmit allocation information of the downlink data channel and information of the second frequency resource together through the downlink data channel. Such information may indicate that UCI channels of different terminals use the same frequency resource, which may lead to multiplexing of the UCI channel.

As another method, the base station acquires an uplink (UL) channel using a sounding reference signal (SRS) transmitted by the terminal, and the base station knows the location of the frequency resource having the highest channel quality in the base station. Can assume If the base station can be configured to trigger the sounding reference signal (SRS) to the terminal or to transmit the sounding reference signal (SRS) to the terminal periodically, the base station can estimate the UL (UL) with the terminal. In this case, the base station may instruct the terminal of the frequency resource position of the radio resource for mapping the UCI channel using the downlink control channel.

As an example, the frequency resource location used in the sounding resource may indicate the frequency resource location of the UCI channel, as indicated by the base station to the terminal in higher layer signaling. In this case, a Radio Resource Control (RRC) parameter having the same function as the sounding resource may be utilized. The base station uses a value such as TC (Transmission Comb), bandwidth configuration variable (BandwidthConfig), bandwidth variable (Bandwidth), frequency hopping bandwidth variable (HoppingBandwidth), frequency domain location information (freqDomainPosition), etc. According to the frequency resource position of the UCI channel can be derived. As an example of an equation applied herein, an equation for defining a frequency resource location of a sounding resource may be applied in TS 36.211 to TS 38.211, or a part of the equation may be modified.

As another example, the base station may transmit a downlink (DL) control channel to deliver a downlink (DL) data channel to the terminal. In this case, a frequency resource of the UCI channel can be indicated to the terminal using a bit field included in the downlink (DL) control channel. The frequency resource may be expressed in two steps, and may correspond to the index of the UCI channel subband to be used by the UE and the frequency resource of the UCI channel applied within the subband.

Two bit fields may be configured in a downlink (DL) control channel of a base station. In this case, the base station may first instruct the UE of the index of the UCI channel partial band or the band portion, and secondly, the index of the UCI channel partial band or the band portion. These two indices can be used for other purposes in the downlink (DL) control channel. For example, the index indicating the UCI subband may be expressed by reusing a field indicating a resource related to a sounding reference signal (SRS). At this time, the base station can adjust to have a distributed PRB allocation in one frequency index (freq index).

주파수 다중화Frequency multiplexing

There may occur a case in which the UE needs to transmit a UCI channel before the base station sets the sounding resource to the UE. In this case, the BS may transmit the multiplexing gain. The base station may set a unit of time resources or units of frequency resources used for frequency multiplexing in consideration of coexistence of UCI channels, coexistence with an uplink (UL) data channel, or coexistence with sounding resources. . Here, the time unit may be a symbol or subslot, and the frequency unit may be a subcarrier or a resource block (RB) or a partial band or a band part.

As an example of a method of obtaining the multiplexing gain, single cluster transmission may be considered. Although data is transmitted one or two times in time, the UCI channel transmitted by the UE may use different frequency resources in units of one or two symbols or subslots (frequency hopping). Here, the frequency resource to be applied includes the start position and bandwidth of the frequency transmitting the UCI channel, and the numerology of the waveform used by the UCI channel (eg, subcarrier spacing, cyclic prefix length) is the numerology of the waveform used by the data channel. The same applies to.

The signaling method of the frequency resource may use a value previously known in the standard as it is, or use only upper layer signaling, or may instruct the terminal in a combination of higher layer signaling and downlink control channel. In the case of the initial access step in which the base station does not make a higher layer setting (for example, RRC setting) to the terminal, the base station uses a value determined by the standard (TS), or uses the UE resource frequency resource from the system information. This can be recognized. After the base station sets the upper layer to the terminal, the base station may indicate the frequency resource of the UCI channel by a combination of the upper layer signaling and the downlink control channel. The base station may transmit a downlink control channel in a group common control channel, and in the case of a UCI channel transmitting HARQ-ACK, the base station may transmit a downlink control channel in a downlink control channel scheduling a downlink (DL) data channel. It can indicate a frequency resource.

For example, the base station may indicate a time resource and a frequency resource of a UCI channel transmitting HARQ-ACK using m bits in a downlink (DL) control channel scheduling a downlink (DL) data channel. In this case, the base station may set the time resources and frequency resources of the 2 ^ m UCI channel to the higher layer signaling to the terminal. To this end, the base station should have enough channel information of the frequency band by receiving the sounding reference signal (SRS) from the terminal in advance, and uses the channel information to transmit the frequency resource of the UCI channel to the terminal as bits belonging to the downlink control channel. Can be directed. In this case, since the base station instructs to transmit the UCI channel by applying frequency selective scheduling, the terminal may perform a single cluster transmission. However, in a scenario in which the reception quality of the UCI channel is further improved or the UCI channel should be periodically transmitted, the base station may be configured to perform single or multiple cluster transmission to the terminal.

On the other hand, if the UCI channel consists of one subslot and the subslot consists of two or more symbols, the subcarrier index set is different for each symbol, or in the set of consecutive symbols, the symbol has the same subcarrier index set, but the symbol Frequency diversity can be obtained by transmitting the UCI channel so that the subcarrier index sets are different from each other in the different sets. When the UCI channel is configured using two or more subslots, the UE may obtain frequency diversity by transmitting the UCI channel differently for the location of the frequency resources of each subslot.

For example, in the case of a UCI channel using two symbols in FIGS. 6 to 8, different subcarrier sets or resource block (RB) sets may be used for each symbol. 9 and 10, for the third UCI channel, the first subslot, the second subslot, and the third subslot constituting the third UCI channel may use different subcarrier sets or resource block (RB) sets. The channel can be transmitted.

Depending on the configuration of the base station, a set of subcarriers or a set of resource blocks (RBs) used by the UCI channel may be different from each other, or may be the same. 36 shows an example of an uplink (UL) control channel transmitted using the same subband. Meanwhile, FIG. 40 shows an example of an uplink (UL) control channel transmitted using different subbands.

The base station may set the same sub-band of the uplink (UL) control channel used in the first symbol and the second symbol to the terminal. As a first method of signaling a sub-band of an uplink (UL) control channel by a base station, a base station may explicitly indicate that frequency resources of a first symbol and a second symbol are the same. In addition, as a second method for the base station to signal a sub-band of an uplink (UL) control channel to the terminal, a UCI channel using two symbols or one subslot may be configured for the terminal. In this case, it can be understood that the UE implicitly transmits the same frequency resource. Here, the base station may configure one subslot with two or more symbols. Hereinafter, one subslot composed of two symbols will be described as an example.

Referring to FIG. 37, the UE may perform different rate matching for all symbols belonging to the UCI channel 510. That is, the terminal may perform different coding rate matching for each symbol. The interference between the sounding resource set by the base station to another terminal and the UCI channel 510 may occur. In the present invention, the terminal transmitting the UCI channel 510 may avoid the sounding resource according to the setting of the base station. A set of subcarriers can be used.

In this case, the base station may instruct the terminal the TC used in the UCI channel in the symbols constituting the UCI channel 510. In addition, the base station may instruct the terminal to not use the TC. In this case, the higher layer signaling may be used when the base station instructs the terminal of the available TC or the TC not to be used. The base station may set an unused subcarrier set or zero power reference signal 520 to the terminal in order for the base station to indicate to the terminal the TC not to be used by the terminal.

The UE may encode an UCI channel and map a resource element (RE) by avoiding an unused subcarrier set or zero power reference signal 520, or may encode an UL data channel and map a resource element (RE). have. For example, when the base station sets the zero power (ZP) sounding resource to the terminal, the terminal does not map the resource element (RE) to the zero power (ZP) sounding resource. In addition, the UE may perform encoding or spreading for a set of remaining subcarriers belonging to the partial band.

FIG. 37 illustrates an example of mapping a UCI channel to a set of subcarriers belonging to a partial band by avoiding the zero power reference signal 520 when the UE transmits the UCI channel to one or more clusters. If the UE encodes or spreads UCI using a ZC sequence, the coding rate, spreading gain, length of the ZC sequence, and TC may be different for each symbol.

For different rate matching per symbol methods, see UCI channel transmission method (Method 1) that does not use the reference signal RS described with reference to FIGS. 3 to 5 and FIGS. 6 to 8. It can be applied to both the transmission method (method 2) of the UCI channel using the reference signal (RS) described above.

Hereinafter, as illustrated in FIG. 7, a method (transmission method 2) of a UCI channel for transmitting a reference signal RS in all symbols will be described as an example.

Referring to FIG. 38, in a partial band used by a UCI channel, the UE may distinguish a set of subcarriers transmitting the reference signal 510 of the UCI channel from a set of subcarriers transmitting the UCI. Here, all of the frequency resource positions of the reference signal 510 of the UCI channel may be set to be the same. Since the subcarriers transmitting the reference signal 510 of the UCI channel are the same, orthogonal cover codes may be applied in the time domain when the first symbol and the second symbol are consecutive or not far apart.

For example, the base station may instruct [1, -1] as the orthogonal sequence (OCC) to the first terminal and [1, 1] as the orthogonal sequence (OCC) to the second terminal. In this case, the base station may distinguish between the UCI channel of the first terminal and the UCI channel of the second terminal by using an orthogonal sequence (OCC). Since the terminal transmits the reference signal 510 of the UCI channel in the same set of subcarriers, the base station can more accurately estimate the channel value in the set of subcarriers. Through this, the base station may be set so as to constantly lower the transmission power of the reference signal 510 of the UCI channel. That is, it is possible to provide an effect that can reduce the power consumption of the terminal.

Referring to FIG. 39, the UE may set a location of a subcarrier for transmitting the reference signal 510 of the UCI channel for each symbol.

The base station may receive the reference signal 510 of the UCI channel transmitted in different subcarriers and different symbols, and perform channel estimation using the received reference signal 510 of the UCI channel. Thereafter, interpolation may be applied to estimate a channel experienced by the resource element RE that transmits the UCI. Since the resource elements RE of the reference signal RS are scattered in the time and frequency domains of the UCI channel, the error by interpolation may be the same when the subcarriers of the reference signal 510 of the UCI channel described with reference to FIG. 38 are the same. Can be smaller than That is, channel estimation accuracy of the base station can be increased through channel interpolation.

Referring to FIG. 40, similar to the method of using the same subband for each symbol, the UE may arrange the reference signal 510 of the UCI channel when using different subbands. In this case, the reference signal 510 of the UCI channel may be disposed in each of the first cluster band in the first symbol and the cluster band in the second symbol. The terminal may transmit the UCI channel in which the reference signal 510 of the UCI channel is disposed to the base station.

The terminal may transmit one cluster in one symbol corresponding to the same time resource. The UE may apply different bandwidths and different TCs to the first cluster transmitted in the first symbol and the second cluster applied in the second symbol. Meanwhile, when the terminal transmits the first symbol and the second symbol in succession, the transmission power set by the base station may be the same for each symbol. Alternatively, a preset transmission power may be applied to the first symbol, and a transmission power having a difference (for example, a power offset) from the preset transmission power may be applied to the second symbol. Here, the power offset is preferably set to a value small enough to reduce interference between the first symbol and the second symbol.

41 is a diagram illustrating a multi-cluster transmission method for obtaining a multiplexing gain. In FIG. 41, an UCI channel using three clusters is shown as an example.

Referring to FIG. 41, the terminal may utilize UCI resources using one or more consecutive frequency units (540, cluster, hereinafter referred to as a cluster) in the frequency domain (multi-cluster transmission). Here, the terminal may transmit the same symbol or the same subslot in unit time. Applying such a transmission method increases the PAPR of the terminal, so that the operating power of the power amplifier used by the terminal can be lowered, and the multiplexing gain of the frequency domain can be obtained instead. Through this, the SINR gain can be obtained at the base station.

As an example, the terminal may apply the multi-cluster transmission method and transmit the UCI channel to the base station without including the reference signal RS in all clusters.

As another example, the UE may transmit a UCI channel to the base station by applying a multi-cluster transmission method and including a reference signal (RS) in all clusters.

As another example, the UE applies a multi-cluster transmission method, and does not include the reference signal RS in one cluster of the three clusters, and includes the reference signal RS in the remaining two clusters to thereby UCI channel. May be transmitted to the base station.

In order to generate one cluster 540 belonging to the UCI channel, the terminal may generate resources such as bandwidth and sequence in the same manner as the sounding reference signal (SRS), and through this, sounding resources or UCI channels of other terminals. Coexistence can be considered.

The base station may inform the terminal of the resources of each cluster 540 used by the terminal using higher layer signaling or higher layer signaling and a downlink control channel. Here, as a first method of determining the length of a sequence used in a sounding resource, sounding is based on a sum of the bandwidth of the first cluster 540, the bandwidth of the second cluster 540, and the bandwidth of the third cluster 540. The length of the sequence used by the resource can be determined. A second method of determining the length of a sequence used in a sounding resource, wherein the first sounding resource corresponds to the first cluster 540, the second sounding resource corresponds to the second cluster 540, and The length of the sequence used in the sounding resource may be determined such that the 3 sounding resource corresponds to the third cluster 540.

In the first method of determining the length of a sequence used in a sounding resource, the sequence of the reference signal RS or the sequence applied to the UCI may be regarded as one resource unit over multiple clusters and mapped. In the second method of determining the length of the sequence used in the sounding resource, the sequence of the reference signal RS or the sequence applied to the UCI may be regarded as one resource unit for each cluster 540 and mapped. have.

The amount of power the terminal applies to each cluster 540 depends on the setting of the base station, and the base station transmits power to each cluster 540 according to the amount of power used by sounding resources in the partial band to which each cluster 540 belongs. You can set the size of. However, since this method can increase the amount of control information of the base station, it is preferable to set the transmission power of all the clusters 540 equally.

The terminal may transmit the UCI channel in a single cluster or multiple clusters unless receiving a separate instruction from the base station. Here, the separate indication may be set to the terminal by higher layer signaling at the base station. In addition, a separate indication may be included in a downlink control channel for scheduling downlink (DL) data in the base station.

As an example, when the terminal performs periodic CSI feedback and scheduling request (SR), a separate indication may not be received from the base station. In this case, when the UE transmits the number of clusters that are already set up or activated, and when the UE feeds back the HARQ-ACK, the UE receives a separate indication of the DL data channel from the base station. do. Therefore, the terminal may consider the case of transmitting the UCI channel using a single cluster or multiple clusters according to the indication of the base station.

As another example, when the terminal needs to transmit the CSI and the HARQ-ACK on the same UCI channel, a separate indication may be received from the base station. When the terminal receives such an instruction, the terminal may derive a frequency resource (eg, cluster index) within an uplink (UL) system band of the terminal. In addition, when receiving the indication, the terminal may derive a time resource (eg, a subslot index or a symbol index) within the corresponding slot. In addition, when the terminal receives such an instruction, the terminal may derive a frequency resource (eg, cluster index) within an uplink (UL) system band of the terminal.

Even after the base station sets the sounding resource to the terminal, both coexistence with the sounding resources and multiplexing of the UCI channel may be considered. To this end, the terminal may use one or more cluster 540. The UE may transmit a UCI channel using a plurality of clusters 540 in one or more unit times, where the unit time may mean a symbol or a sub slot. Meanwhile, the terminal may use different clusters 540 every one unit time. If the transmission resource of the UCI channel is already configured in multiple clusters, multiple clusters may be used in one unit time. Here, the resource used by one cluster may be set by applying one of the resource setting methods described with reference to FIGS. 36 to 40.

UCI 채널들의 공존Coexistence of UCI Channels

Coexistence between UCI channels may be considered, and each UE may transmit each UCI channel to the same time resource and frequency resource. In the serving base station, in order to distinguish between these UCI channels, the base station assigns a unique phase modulation (UE) -specific cyclic shift (phase modulation) to each UE by using a higher layer configuration or a combination of a higher layer configuration and a downlink control channel. Each terminal may be instructed. Here, the base station can randomize the interference of the UCI channels by supporting a unique polarization modulation pattern to each terminal.

In the case of a communication system operating at a high frequency (eg, 6 GHz or more), the terminal may include a scenario of transmitting a UCI channel to a serving base station while changing precoding. Since the terminal may apply a number of preprocessing, it is possible to efficiently use radio resources by keeping the number of symbols of one UCI channel small.

In addition, different UCI types may include different scenarios for delivering different UCI types. The UE may generate a UCI channel including a channel quality indicator (CQI) and a UCI channel including a HARQ-ACK as different UCI channels and transmit the same to a serving base station. In this case, the UCI channel including the CQI occupies a large number of symbols, but the UCI channel including the HARQ-ACK may occupy a small number of symbols.

In addition, each UCI channel may include another scenario for delivering UCI derived from different usage scenarios. The UE transmits HARQ-ACK for a downlink (DL) data channel of an NR (New Radio) enhanced Mobile BroadBand (eMBB) in a UCI channel occupying a large number of symbols, and NR URLLC (Ultra-reliable, Low-Latency Communication) HARQ-ACK for a downlink (DL) data channel may be transmitted in a UCI channel occupying a small number of symbols. The scenarios described above may correspond to a case in which one UE transmits two or more UCI channels having different lengths in one slot.

When generating a UCI channel by assigning a priority to the UCI type, the UE may encode only the UCI type having a high priority and map it to the UCI channel. In addition, the UE further considers not only the UCI type but also a usage scenario or a Logical Channel Identification (LCID), thereby differenting the UCI for the NR eMBB, the UCI for the NR URLLC, and the UCI for the mMTC. Priority can be given. In addition, in case of a communication system interworking NR (eg, 5G communication system) and LTE (eg, 4G communication system), not only UCI type and usage scenario but also RAT (Radio Access Technology) ) Can be given priority. In this case, the terminal may be applied when the LTE carrier is set to the primary cell (PCell) and the NR carrier is set to the secondary cell (SCell) to perform LTE-NR dual connectivity. Through this, the UCI generated in the NR carrier can be transmitted using the UCI channel in the LTE carrier. In addition, the UCI generated in the NR carrier may be transmitted in the NR carrier, and the UCI generated in the LTE carrier may be transmitted in the LTE carrier. However, since the transmission power is limited, the terminal may select only a part of UCI using the priority between UCIs applicable in this case, and transmit the selected UCI to the serving base station. In addition, the terminal may derive an appropriate parameter from the power control applied when transmitting the UCI channel (s) according to the priority of the UCI.

Coexistence between these UCI channels may be divided into a case where the UCI channels have the same length and a case where the UCI channels have the same length. Hereinafter, a UCI channel occupying one or two symbols will be referred to as a short UCI channel, and a UCI channel occupying four or more symbols will be referred to as a long UCI channel.

In the same slot, a case where a first terminal transmits a short UCI channel and a second terminal transmits a long UCI channel may be considered. In this case, the serving base station of the first terminal and the serving base station of the second terminal may be different from each other, and interference may occur when the serving base stations are different from each other.

Since the first terminal can transmit the HARQ-ACK for the URLLC DL data channel to the short UCI channel, the symbol occupied by the short UCI channel in the UL slot can be arbitrarily located within the UL slot.

As an example, in the FDD system, the serving base station may transmit the URLLC DL data channel to the first terminal through the DL slot. The first terminal may receive the URLLC DL data channel from the serving base station and transmit a short UCI channel to the base station at the HARQ-ACK timing indicated by the URLLC DL control channel. According to this HARQ-ACK timing, the terminal may transmit in any symbols belonging to the UL slot.

As another example, in a TDD system, symbols transmitting a short UCI channel for a URLLC DL data channel of a serving base station may belong to the UL region of the same slot or the next slot. When the downlink control channel and the corresponding UCI channel belong to the same slot, in order to ensure the time required for processing of the first terminal, the HARQ-ACK timing may be signaled to the first terminal to be located behind the corresponding slot. . On the other hand, when belonging to the next slot, since the time required for processing of the first terminal is sufficient, it is possible to signal to the first terminal so that the HARQ-ACK timing is located in front of the slot. Therefore, considering the scenario of operating in both TDD and FDD, the short UCI channel transmitted by the first terminal may coexist in the form of TDM or FDM in the same slot as the long UCI channel transmitted by the second terminal.

As a separate scenario described above, there may exist a scenario in which the UE additionally transmits a higher priority UCI type while the UE is already transmitting the UCI channel.

For example, while the UE transmits the UCI channel for the NR eMBB, there may be a scenario in which the UCI for the DL data channel of the NR URLLC should be transmitted. This scenario may correspond to the case where the UE includes a lower rank UCI when generating the UCI channel because the UE does not know the existence of the UCI for the DL data channel of the NR URLLC in advance. Therefore, three methods can be considered to support this scenario.

As a first method, a method of additionally mapping additionally generated UCI to UCI channel may be applied. As a second method, a method in which additionally generated UCI is generated as a separate UCI channel and the two UCI channels are temporally multiplexed (TDM) can be applied. As a third method, an additional UCI channel may be generated as a separate UCI channel to apply two-frequency multiplexing (FDM).

Hereinafter, the first UCI and the second UCI further generated will be described separately.

As a first method , the UE may further map the second UCI to the UCI channel. The terminal may map the encoded second UCI to the resource element (RE) included in the UCI channel. Here, the first UCI may be encoded and then mapped to the UCI channel. Thereafter, the encoded second UCI may be mapped, and a portion of the first UCI which is already mapped may be punctured. Meanwhile, as another method, the UE may map the encoded second UCI to the UCI channel and then map the encoded first UCI. In this process, the UE may perform rate matching. Although the second UCI is additionally generated, but has a higher priority than the first UCI, the UE may map using a resource element (RE) that is equal to or closer to the DM-RS of the UCI channel.

As a second method , the UE may perform time multiplexing by generating the first UCI and the second UCI as separate UCI channels. The first UCI channel including the first UCI and the second UCI channel including the second UCI may have different lengths. For example, the first UCI channel may have four or more symbols, and the second UCI channel may have one or two symbols. According to the relative positions of the first and second UCI channels can be divided into several cases. Since the second UCI channel is always located at both ends of the first UCI channel, the second UCI channel may be transmitted in time earlier than the first UCI channel. In contrast, the second UCI channel may be transmitted later in time than the first UCI channel. If the terminal can transmit the second UCI channel at any position within the slot, it may be divided into a part A of the first UCI channel, and a part B of the second UCI channel and the first UCI channel. The first UCI channel and the second UCI channel may use different bands (eg, RB index) and may have different bandwidths.

The terminal may perform frequency hopping on the first UCI channel and the second UCI channel to use the same frequency resource for a predetermined time interval, and use another frequency resource for the subsequent time interval. In case of using different frequency resources, the base station needs to estimate the UL channel, and thus, the terminal may separately transmit the DM-RS to the base station. Therefore, when performing time multiplexing between UCI channels, this DM-RS overhead can be considered. In this case, since the second UCI channel is transmitted in a time multiplexing manner, frequency resources used by the first UCI channel can be maximized. If the UE transmits the DM-RS resources for the second UCI channel separately, the serving base station uses a DM-RS resource for the first UCI channel and a DM-RS resource for the second UCI channel to UL with higher quality. The channel can be estimated. Therefore, the UE may separately transmit some DM-RS resources in a manner of separately transmitting DM-RS resources for the second UCI channel but lowering the density of resource elements (RE) used for the second UCI. On the other hand, even when the terminal does not transmit the DM-RS resources, the serving base station can estimate the UL channel with a suitable quality. In this case, the second UCI channel does not allocate a separate DM-RS or utilizes a few DM-RSs, and the serving base station includes a second UCI channel included in the second UCI channel using the DM-RS of the first UCI channel. UCI can be decoded.

When the first UCI channel and the second UCI channel have different bandwidths, the UE may separately transmit the DM-RS for the second UCI channel. In this case, the terminal may match the bandwidth of the second UCI channel with the bandwidth of the first UCI channel. Therefore, when time multiplexing the second UCI channel, the terminal does not transmit a portion of the first UCI channel but transmits the second UCI channel instead, but the terminal may transmit the DM-RS of the first UCI channel to the base station. To this end, the first UCI channel and the second UCI channel should apply the same preprocessing scheme. Therefore, the preprocessing scheme applied by the terminal when transmitting the second UCI channel alone is different from the preprocessing scheme applied by the terminal to the second UCI channel when transmitting the second UCI channel for the purpose of TDM with the first UCI channel. Can be.

As a third method , the UE may perform frequency multiplexing by generating the first UCI and the second UCI as separate UCI channels. Since the UE must transmit two UCI channels at the same time, the UE located at the coverage boundary cannot perform the UE with insufficient power. If, the serving base station has uplink signaling or radio resource controller (RRC) simulaneous PUSCH and PUCCH transmission so that the serving base station simultaneously transmits an uplink (UL) data channel and an uplink (UL) control channel to the user equipment. In the slot for simultaneously transmitting the first UCI channel and the UL data channel, it may be difficult for the terminal to further transmit the second UCI channel. On the other hand, when the UE transmits only the first UCI channel, the UE may additionally transmit the second UCI channel to the base station.

자원 할당의 활성화 및 비활성화 (activation to track channel variation)Activation to track channel variation

The UCI channel may or may not perform frequency hopping within the UL slot, and the UE may determine whether to perform frequency hopping according to higher layer signaling of the serving base station. Here, the UE cannot perform frequency hopping when the UCI channel is configured with only one symbol.

As an example, since frequency multiplexing gain can be obtained when frequency hopping is performed, an error of demodulating a UCI channel in a serving base station can be greatly reduced. However, since frequency hopping is performed, the number of symbols (reference signal symbol and UCI symbol) constituting the UCI channel is reduced by about half, thereby degrading the performance of channel estimation and reducing the multi-user gain represented by OCC.

As another example, a UCI channel that does not perform frequency hopping increases the performance of channel estimation and increases multi-user gain but cannot obtain frequency multiplexing gain. Therefore, the reception quality of the UCI channel obtainable by the serving base station may be affected by the fading characteristics of the UL channel.

If the UL channel fading between the UE and the serving base station is good, the serving base station may perform higher layer signaling so that the UCI channel does not perform frequency hopping. On the other hand, if the fading of the UL channel between the UE and the serving base station is deep (deep fading), the serving base station may perform higher layer signaling so that the UCI channel performs frequency hopping.

The serving base station tracks the state of an uplink (UL) channel through a DM-RS of a sounding reference signal (SRS) or an uplink (UL) control channel of a terminal or a DM-RS of an uplink (UL) data channel. ) can do. Therefore, when the fading of the uplink (UL) channel is bad, since the serving base station knows the state (UL CSI) of the uplink (UL) channel in advance, when the UE transmits the UCI channel, the corresponding uplink (UL) frequency resource is used. You can disable it.

In case of indicating a resource transmitted by the UCI channel in a downlink (DL) control channel, the UE can transmit the UCI channel using the resource corresponding to the index received from the serving base station. Such a resource may include at least one of a frequency resource, an RB index, a code resource, a time resource, and a symbol index used by the UCI channel.

The serving base station may inform the terminal of a bandwidth part (BWP) or a sub-band in the DL control channel (PDCCH). In the following, embodiments will be described without distinguishing the band portion and the partial band. In this case, the terminal may include information about the UL band portion to which the UE should transmit the UCI channel, instead of including only the DL band portion. Accordingly, the DL control channel received by the terminal may include not only the scheduling information of the DL data channel but also the index of the UL band portion. Since the serving base station includes the index of the DL band part within the scheduling information of the DL data channel, the terminal can know both the index of the DL band part and the index of the UL band part. The serving base station may include the index of the DL band part and the index of the UL band part as independent fields of the DL control channel, respectively. However, the index of the band portion may be expressed as a combination to indicate an ordered pair of the index of the DL band portion and the index of the UL band portion as a separate unified index. This approach has the advantage of reducing the amount of fields occupied by the DL control channel. To this end, the serving base station may define an ordered pair of band portions that the aggregation index means by using higher layer signaling to the terminal. Subsequently, the terminal may receive the combined index indicated in the DL control channel and may know the DL band portion and the UL band portion.

The serving base station preferably adjusts the value of the field in the DL control channel in order to adjust the frequency resource transmitted by the aggregation index and the UCI channel. The terminal demodulates accordingly and may use a frequency selectivity characteristic without performing frequency hopping.

For example, when the serving base station transmits DL data to the terminal and receives the HARQ-ACK, the serving base station may apply the above-described method. If the UE multiplexes other UCIs other than HARQ-ACK in the same UCI channel, the above-described method may be applied. This type of UCI may correspond to UCI (CSI report, L1 RSRP, SR) that occurs periodically.

When the serving base station indicates the resources transmitted by the UCI channel in higher layer signaling, the resources used by the UCI channel cannot be dynamically selected by the serving base station. In order to overcome this disadvantage, the serving base station may set a plurality of UCI channels in the upper layer signaling to the terminal, and then select one UCI channel using MAC signaling or DL control channel. Here, the region of resources for the UCI channel may be distributed over several frequency resources. The serving base station may select the best frequency resource among these multiple frequency resources using UL CSI, and may instruct the terminal to transmit the UCI channel using the selected frequency resource. The specific signaling method may be applied differently for each UCI. The UE knows a frequency resource to be used when transmitting the UCI channel, it can be used when transmitting the UCI channel.

For example, when the terminal is applied to periodically generated UCI (CSI report, L1 RSRP, SR), the serving base station may select one UCI channel among a plurality of UCI channel resources configured for the terminal according to the UL CSI. . Thereafter, the serving base station may transmit the selected UCI channel to the terminal using MAC signaling or DL control channel. After a predetermined time that the serving base station and the terminal know each other, the terminal can recognize the resources (frequency, code, time) of the UCI channel to be applied at the time of transmitting the UCI channel. The terminal may transmit the UCI channel using this resource. If the serving base station determines that the UL CSI has changed, the serving base station may select a resource of another UCI channel and transmit it to the terminal through MAC signaling or DL control channel.

Referring to FIG. 42, the base station may derive resource positions (frequency resource position and time resource position) of the UCI channel for transmission of the UCI channel (S10). The time resource location information may consist of one or more UL subslots, which may be located in the middle of the last symbol or UL slot. Here, the base station uses the UCI using values such as a transmission comb (TC) value, a bandwidth configuration variable (Bandwidth Config), a bandwidth variable (Bandwidth), a frequency hopping bandwidth variable (Hopping Bandwidth), and frequency domain position information (freq Domain Position). The frequency resource location of the channel can be derived.

Subsequently, the base station may instruct the terminal of the resource location of the UCI channel (S20). That is, the base station can transmit the information of the resource location for the transmission of the UCI channel to the terminal. For example, the base station may transmit the resource location of the UCI channel to the terminal using a downlink control channel. As another example, the base station may transmit the resource location of the UCI channel to the terminal using the RRC parameter. As another example, when the base station transmits a DL data channel to the terminal, the base station may indicate the frequency resource of the UCI channel to the terminal using a bit field included in the downlink control channel. The base station measures the UL reception power of the terminal to control the terminal to have an appropriate transmission power, and instructs the terminal the number of subslots for transmitting the UCI channel in a higher layer configuration.

Subsequently, the terminal may map the resource element RE of the UCI channel based on the information on the resource location of the UCI channel received from the base station (S30). As an example, the terminal may map the resource elements (RE) of the UCI channel in the order of time resources, and then map the resource elements (RE) of the UCI channel in the order of the frequency resources. As another example, the terminal may map the resource element (RE) of the UCI channel in the order of frequency resources, and then map the resource element (RE) of the UCI channel in the order of time resources.

Here, the UCI channel may include a reference signal (RS), and when the UCI channel is set to a single symbol to map the resource element of the UCI channel and the resource element of the reference signal (RS) using frequency multiplexing (FDM) Can be.

Subsequently, the terminal may arrange the UCI channel in at least one symbol and transmit a subframe including the at least one symbol to the base station. Through this, the terminal may transmit the UCI channel to the base station (S40).

Referring to FIG. 43, the base station may recognize a service type (eg, eMBB or URLLC) requested by the terminal and transmit a scheduling grant to the terminal. The base station may set a scheduling request (SR) resource for each service type and allocate it to the terminal so that the scheduling request (SR) may be transmitted from the terminal for each service type (eMBB, URLLC) (S110). Here, the base station may set different periods or different transmission time intervals (TTIs) or different parameters (numerology or subcarrier spacing) differently.

In detail, the base station may allocate a scheduling request (SR) resource for providing an enhanced mobile broadband service (eMBB) to the terminal. In addition, the base station may allocate a scheduling request (SR) resource for providing the ultra-reliable low-latency communication (URLLC) service to the terminal. In addition, the base station may allocate a scheduling request (SR) resource for providing a service of the mMTC (massive machine type communications) to the terminal.

Subsequently, the terminal may determine a service type to be provided from among a plurality of service types (eg, eMBB, URLLC, and mMTC) (S120). That is, the terminal may select (eg, URLLC) a service type to be provided among eMBB, URLLC, and mMTC service types.

Subsequently, the terminal may map the resource element of the UCI channel of the selected URLLC service and the resource element of the reference signal RS to a symbol (S130). In this case, the UCI channel for the URLLC service may be mapped to a symbol by 1 bit or 2 bits or more. In addition, a UCI channel for an eMBB service may be mapped to a symbol by 1 bit or 2 bits or more. In addition, the UCI channel for the mMTC service may be mapped to a symbol with one or two bits or more.

Subsequently, the terminal may transmit the UCI and the scheduling request to the base station by using the scheduling request resource according to the service type (S140). In this case, the terminal may select a scheduling request resource of a service (eg, URLLC) to be provided from among scheduling request resources received from the base station, and transmit the UCI channel to the base station. The base station may classify a service to be provided to the terminal based on the scheduling request received from the terminal.

Meanwhile, the base station sets a scheduling request (SR) resource regardless of the service type to the terminal, and the terminal may deliver a service to be provided to the base station by expressing the scheduling request in several bits. For example, the terminal may express the scheduling request (SR) for the eMBB uplink, the scheduling request (SR) for the URLLC uplink, and the scheduling request (SR) for the mMTC uplink as information of one bit or two bits or more. have.

As another example, the base station sets the scheduling request (SR) resources for the URLLC service to the terminal, the terminal may generate the scheduling request (SR) by expressing the amount of the uplink buffer in a few bits. For example, the terminal may generate a scheduling request (SR) by dividing the amount of URLLC traffic into several steps according to the size, and mapping the information into two bits of information.

In this case, when the terminal transmits only the scheduling request (SR) to the base station, it is not necessary to transmit the UCI, and thus, the UCI channel including only the scheduling request (SR) may not be transmitted to the base station. The symbol of the UCI channel may be configured with one or two or more, and the base station may be configured to transmit a sounding reference signal (SRS) in the same subband as the UCI channel for transmitting the UCI. Radio resources may be allocated to each terminal so that the first terminal transmits the UCI channel to the base station and the second terminal transmits the sounding reference signal (SRS) to the base station. The first terminal may map the resource element RE of the reference signal RS to the UCI channel. In addition, the first terminal may map the resource element RE of the reference signal RS and the resource element RE of zero power ZP to the UCI channel.

The method and apparatus for transmitting uplink control information according to an embodiment of the present invention may vary the time resource for transmitting uplink control information (UCI) in the terminal, and transmit the UCI with a small amount of time resource in the terminal. In addition, the UE may reduce the detection error of the UCI channel at the base station by mapping the HARQ-ACK bit using the resource element RE without using the reference signal RS when transmitting the UCI channel.

The method and apparatus for transmitting uplink control information according to an embodiment of the present invention allow the terminal to use a reference signal (RS) when transmitting a UCI channel, and to allow the first symbol and the second symbol to have different subcarrier index sets. Increase the detection performance of the UCI channel. In addition, the base station is configured to allow transmission of the sounding reference signal (SRS) in the same subband as the UCI channel transmitting the scheduling request (SR), the first terminal transmits the UCI channel, the second terminal sounding In the case of transmitting the reference signal SRS, a transmission comb (TC) may be applied to the UCI channel to prevent a collision between the UCI channel and the sounding reference signal SRS. In addition, by repeatedly transmitting the sounding reference signal (SRS) to the base station with the same resource (frequency and code) for two symbols, the terminal can improve the channel estimation performance at the base station. In addition, by repeatedly transmitting the sounding reference signal (SRS) to the base station with different resources (frequency and code) for two symbols, it is possible to reduce the time for obtaining the channel state information (CSI) from the base station.

The method and apparatus for transmitting uplink control information according to an embodiment of the present invention apply up to a sounding reference signal occation to perform uplink management between a terminal and a base station so that uplink is not cut even in a communication environment having a high probability of failure. Can be managed.

In the method and apparatus for transmitting uplink control information according to an embodiment of the present invention, the base station allocates frequency resources used by the terminals from the edges, and the terminal transmits a wide bandwidth by transmitting a UL data channel in a DFT-s-OFDM waveform. Can transmit a lot of data. In addition, the terminal located near the base station transmits the sounding reference signal (SRS) over a broadband, thereby reducing the time to obtain the channel state information (CSI) from the base station. In addition, the base station matches the center frequency of the terminals, the terminal can reduce the Peak to Average Power Ratio (PAPR) by transmitting the UL data channel to the CP-OFDM.

The methods according to the invention can be implemented in the form of program instructions that can be executed by various computer means and recorded on a computer readable medium. Computer-readable media may include, alone or in combination with the program instructions, data files, data structures, and the like. The program instructions recorded on the computer readable medium may be those specially designed and constructed for the present invention, or may be known and available to those skilled in computer software.

Examples of computer readable media include hardware devices that are specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include machine language code, such as produced by a compiler, as well as high-level language code that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate with at least one software module to perform the operations of the present invention, and vice versa.

Although described with reference to the embodiments above, those skilled in the art will understand that the present invention can be variously modified and changed without departing from the spirit and scope of the invention as set forth in the claims below. Could be.

Claims

In the operating method of a terminal for transmitting uplink control information to a base station,

Receiving resource location information for transmission of an uplink control information (UCI) channel from the base station;

Mapping a UCI to at least one symbol based on the resource location information and mapping a reference signal in consideration of a frequency selection characteristic and a time selection characteristic of a radio channel; And

And transmitting a subframe including the at least one symbol to the base station.
The method according to claim 1,

In the step of mapping the reference signal,

The reference signal is mapped to all subcarriers of one symbol in consideration of the frequency selection characteristic.
The method according to claim 1,

In the step of mapping the reference signal,

The reference signal is evenly mapped to subcarriers of a plurality of symbols in consideration of the time selection characteristic.
The method according to claim 1,

In the step of mapping the UCI,

The resource location information includes time resource location information and frequency resource location information for transmission of the UCI channel,

And mapping the UCI in the time resource order, and subsequently mapping the UCI in the frequency resource order.
The method according to claim 1,

In the step of mapping the UCI,

The resource location information includes time resource location information and frequency resource location information for transmission of the UCI channel,

And mapping the UCI in the frequency resource order and subsequently mapping the UCI in the time resource order.
The method according to claim 1,

The time resource location information indicates at least one subslot composed of one or more symbols.
The method according to claim 1,

The frequency resource position is generated based on a transmission comb (TC) value, a bandwidth setting variable, a frequency hopping bandwidth variable, and frequency domain position information.
The method according to claim 1,

The resource location information,

Received via the downlink control information (DCI) from the base station, the terminal operating method.
The method according to claim 1,

The resource location information,

Method received from the base station through Radio Resource Control (RRC) signaling.
The method according to claim 1,

The resource location information,

Received from the base station through the bit field included in the downlink control channel, the operation method of the terminal.
In the operating method of a terminal for transmitting uplink control information to a base station,

Receiving a scheduling request resource for each service type from the base station;

Selecting a service type to be provided from among the plurality of service types;

Mapping uplink control information (UCI) and a reference signal for a selected service type to a scheduling request resource allocated by the base station; And

And transmitting a subframe including the uplink control information (UCI) and the reference signal to the base station.
The method according to claim 11,

In the step of receiving the scheduling request resource,

Receiving scheduling request resources for each of eMBB (enhanced mobile broadband), URLLC (Ultra-reliable Low-Latency Communication), and mMTC (massive Machine Type Communications) services.
The method according to claim 12,

In the step of mapping to the scheduling request resource,

And mapping the uplink control information (UCI) and the reference signal of the selected service among the eMBB service, the URLLC service, and the mMTC service to the scheduling request resource.
The method according to claim 11,

The scheduling request resource indicates each of a plurality of subslots allocated to different frequency resources, each of the plurality of subslots includes a plurality of symbols,

Mapping the UIC and the reference signal to positions of frequency resources of the plurality of subslots differently in the mapping of the scheduling request resources.
A terminal for transmitting uplink control information to a base station,

A memory in which at least one program is stored;

A processor that executes the at least one program instruction; And

It is connected to the network and the transceiver for performing communication; includes;

The at least one program command,

Receive resource location information for transmission of an uplink control information (UCI) channel from the base station,

Map the UCI to at least one symbol based on the resource location information,

Map the reference signal in consideration of the frequency selection characteristics and time selection characteristics of the wireless channel,

And transmit a subframe including the at least one symbol to the base station.
The method according to claim 15,

The at least one program command,

The reference signal is mapped to all subcarriers of one symbol in consideration of the frequency selection characteristic, or

And the reference signal is mapped to some subcarriers of a plurality of symbols in consideration of the time selection characteristic.
The method according to claim 15,

The at least one program command,

Maps resource elements of the UCI channel in order of time resources included in the resource location information, and then maps resource elements of the UCI channel in order of frequency resources included in the resource location information, or

And mapping resource elements of the UCI channel in the order of frequency resources included in the resource location information, and subsequently mapping resource elements of the UCI channel in the order of time resources included in the resource location information.
The method according to claim 15,

The at least one program command,

And receive the resource location information from the base station via downlink control information (DCI).
The method according to claim 15,

The at least one program command,

And execute the resource location information through radio resource control (RRC) signaling from the base station.
The method according to claim 15,

The at least one program command,

And receive from the base station the resource location information via a bit field included in a downlink control channel.