KR20240093387A - Method and apparatus for interference control between a plurality of smallcells in a wireless communication system - Google Patents

Abstract

This specification proposes a method and apparatus for controlling interference between a plurality of small cells in a wireless communication system.

Description

Method and apparatus for controlling interference between a plurality of small cells in a wireless communication system {METHOD AND APPARATUS FOR INTERFERENCE CONTROL BETWEEN A PLURALITY OF SMALLCELLS IN A WIRELESS COMMUNICATION SYSTEM}

The present invention relates to wireless communication, and more specifically, to a method and apparatus for controlling interference between a plurality of small cells in a wireless communication system.

As smartphones and IoT (Internet of Things) terminals rapidly spread, the amount of information exchanged through communication networks is increasing. Accordingly, the next-generation wireless access technology provides an environment that provides faster services to more users than existing communication systems (or existing radio access technology) (e.g., enhanced mobile broadband communication). )) needs to be considered. To this end, a communication system considering MTC (Machine Type Communication), which provides services by connecting multiple devices and objects, is being developed. In addition, a communication system (e.g., URLLC (Ultra-Reliable and Low Latency Communication)) that takes into account services and/or terminals that are sensitive to communication reliability and/or latency has been developed. there is.

Several technologies are being proposed to meet the various requirements of 5G mobile communications, and one candidate technology for increasing transmission capacity is the small cell structure, which reduces the size of the cell and deploys many cells per unit area. However, as the size of the cell decreases, the problem of inter-cell interference increases and additional problems such as frequent cell changes due to the movement of the terminal arise, and research on this is underway starting with LTE. In 5G, the small cell structure to increase transmission capacity is assumed as the basic mobile network structure, and research is being conducted on technologies to provide continuous service quality regardless of the user's location in the small cell structure.

In an environment where multiple small cells are deployed, interference between cells may occur more frequently. Since the frequent occurrence of interference deteriorates communication efficiency, methods and devices for controlling interference are required.

This specification proposes a method and apparatus for controlling interference between a plurality of small cells in a wireless communication system.

According to the present specification, interference that may occur in a wireless communication system in which a plurality of small cells are deployed can be eliminated. Therefore, communication efficiency is increased.

The effects that can be achieved through specific examples of the present specification are not limited to the effects listed above. For example, there may be various technical effects that a person having ordinary skill in the related art can understand or derive from this specification. Accordingly, the specific effects of the present specification are not limited to those explicitly described in the present specification, and may include various effects that can be understood or derived from the technical features of the present specification.

The following drawings were prepared to explain a specific example of the present specification. Since the names of specific devices or specific signals/messages/fields described in the drawings are provided as examples, the technical features of this specification are not limited to the specific names used in the drawings below.
1 is a conceptual diagram illustrating a wireless communication system according to an embodiment of the present invention.
Figure 2 is an exemplary diagram showing a 3GPP 5G system to which a data transmission method according to an embodiment of the present invention can be applied.
FIG. 3 is a diagram illustrating a resource grid supported by wireless access technology to which this embodiment can be applied.
Figure 4 is a diagram for explaining the bandwidth part (BWP) supported by the wireless access technology to which this embodiment can be applied.
Figure 5 is a diagram illustrating a synchronization signal block in a wireless access technology to which this embodiment can be applied.
Figure 6 shows an example of a small cell structure.
Figure 7 shows examples where interference occurs for a terminal located at the cell edge.
Figure 8 shows an example of a small cell system to which a centralized method is applied.
Figure 9 shows an example of a small cell system to which a distributed method is applied.
Figure 10 shows an example of a TDD resource allocation pattern.
Figure 11 shows an example in which method 2 is applied.
Figure 12 shows another example where method 2 is applied.
13 is a flowchart of an example of a method for interference control according to some implementations of the present disclosure.
14 is a flowchart of another example of a method for interference control according to some implementations of the present specification.
Figure 15 illustrates a communication system 1 applied to the present invention.
Figure 16 illustrates a wireless device to which the present invention can be applied.
Figure 17 illustrates a process for generating a transmission signal in a transmitter.
Figure 18 shows another example of a wireless device applied to the present invention.

Since the present invention can make various changes and have various embodiments, specific embodiments will be illustrated in the drawings and described in detail in the detailed description. However, this is not intended to limit the present invention to specific embodiments, and should be understood to include all changes, equivalents, and substitutes included in the spirit and technical scope of the present invention. While describing each drawing, similar reference numerals are used for similar components.

In this specification, terms such as “first,” “second,” “A,” and “B” may be used to describe various components, but the components should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, a first component may be named a second component without departing from the scope of the present invention, and similarly, the second component may also be named a first component. Additionally, the term “and/or” includes any of a plurality of related stated items or a combination of a plurality of related stated items.

When a component is said to be "connected" or "connected" to another component, it is understood that it may be directly connected to or connected to the other component, but that other components may exist in between. It should be. On the other hand, when it is mentioned that a component is “directly connected” or “directly connected” to another component, it should be understood that there are no other components in between.

The terms used in this specification are merely used to describe specific embodiments and are not intended to limit the invention. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this specification, terms such as “comprise” or “have” are intended to designate the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, but are not intended to indicate the presence of one or more other features. It should be understood that this does not exclude in advance the possibility of the existence or addition of elements, numbers, steps, operations, components, parts, or combinations thereof.

Unless otherwise defined, terms used in this specification, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which the present invention pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning in the context of the related technology, and unless clearly defined in this specification, should not be interpreted in an idealized or excessively formal sense. No.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the attached drawings.

1 is a conceptual diagram illustrating a wireless communication system according to an embodiment of the present invention.

Referring to FIG. 1, the wireless communication system 100 includes a plurality of communication nodes 110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, and 130-3. , 130-4, 130-5, 130-6).

Each of the plurality of communication nodes may support at least one communication protocol. For example, each of the plurality of communication nodes may use a communication protocol based on Code Division Multiple Access (CDMA), a communication protocol based on Wideband CDMA (WCDMA), a communication protocol based on Time Division Multiple Access (TDMA), and a Frequency Division Multiple Access (FDMA)-based communication protocol. Access)-based communication protocol, OFDM (Orthogonal Frequency Division Multiplexing)-based communication protocol, OFDMA (Orthogonal Frequency Division Multiple Access)-based communication protocol, SC (Single Carrier)-FDMA-based communication protocol, NOMA (Non-Orthogonal Multiple Access) Access)-based communication protocols, SDMA (space division multiple access)-based communication protocols, etc. can be supported.

The wireless communication system 100 includes a plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) and a plurality of user equipments (130-1, 130-2, 130-3, 130-4, 130-5, 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 plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 is NodeB, evolved NodeB, and next generation Node B. B, gNB), BTS (Base Transceiver Station), radio base station, radio transceiver, access point, access node, road side unit (RSU), It may be referred to as DU (Digital Unit), CDU (Cloud Digital Unit), RRH (Radio Remote Head), RU (Radio Unit), TP (Transmission Point), TRP (transmission and reception point), relay node, etc. You can. Each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) includes 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, etc.

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 (e.g., long term evolution (LTE), advanced (LTE-A), New Radio (NR), etc. specified 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 a different frequency band or may operate in the same frequency band. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to each other through ideal backhaul or non-ideal backhaul, and ideal backhaul Alternatively, information can be exchanged with each other through non-ideal backhaul. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to a core network (not shown) through ideal backhaul or non-ideal backhaul. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) transmits the signal received from the core network to the 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) is sent to the core network can be transmitted 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 OFDM or another transmission method. In addition, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 supports uplink transmission based on OFDM or DFT-Spread-OFDM or other transmission methods. You can. In addition, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 transmits Multiple Input Multiple Output (MIMO) (e.g., Single User (SU)-MIMO, MU (Multi User)-MIMO, massive MIMO, etc.), CoMP (Coordinated Multipoint) transmission, carrier aggregation transmission, transmission in unlicensed band, direct device to device, D2D) communication (or ProSe (proximity services), etc. may be supported. Here, each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 Operations corresponding to the base station (110-1, 110-2, 110-3, 120-1, 120-2) and/or the base station (110-1, 110-2, 110-3, 120-1, 120-2) ) can perform operations supported by .

For example, the second base station 110-2 may transmit a signal to the fourth terminal 130-4 based on SU-MIMO or LoS MIMO, and the fourth terminal 130-4 may transmit a signal to the fourth terminal 130-4 based on SU-MIMO or LoS MIMO. Alternatively, a signal may be received from the second base station 110-2 using the LoS MIMO method. 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 method, and the fourth terminal 130-4 and the fifth terminal 130-5 can each receive a signal from the second base station 110-2 by the MU-MIMO method. 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 the CoMP method, and the fourth terminal 130-4 may transmit a signal to the fourth terminal 130-4. The terminal 130-4 can receive signals from the first base station 110-1, the second base station 110-2, and the third base station 110-3 using the CoMP method. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) has a terminal (130-1, 130-2, 130-3, 130-4, Signals can be transmitted and received based on 130-5, 130-6) and CA methods.

The first base station 110-1, the second base station 110-2, and the third base station 110-3 each coordinate D2D communication between the fourth terminal 130-4 and the fifth terminal 130-5. (coordination), and each of the fourth terminal 130-4 and the fifth terminal 130-5 communicates D2D through coordination with each of the second base station 110-2 and the third base station 110-3. can be performed.

Hereinafter, even when a method performed in a first communication node among communication nodes (e.g., transmission or reception of a signal) is described, the corresponding second communication node is similar to the method performed in the first communication node. A method (eg, receiving or transmitting a signal) may be performed. That is, when the operation of the terminal is described, the corresponding base station can perform the operation corresponding to the operation of the terminal. Conversely, when the operation of the base station is described, the corresponding terminal can perform the operation corresponding to the operation of the base station.

Also, hereinafter, downlink (DL) refers to communication from the base station to the terminal, and uplink (UL: Uplink) refers to communication from the terminal to the base station. In the downlink, the transmitter may be part of the base station and the receiver may be part of the terminal. In the uplink, the transmitter may be part of the terminal and the receiver may be part of the base station.

Recently, as smartphones and IoT (Internet of Things) terminals have rapidly spread, the amount of information exchanged through communication networks is increasing. Accordingly, the next-generation wireless access technology provides an environment that provides faster services to more users than existing communication systems (or existing radio access technology) (e.g., enhanced mobile broadband communication). )) needs to be considered. To this end, the design of a communication system considering MTC (Machine Type Communication), which provides services by connecting multiple devices and objects, is being discussed. In addition, the design of a communication system (e.g., URLLC (Ultra-Reliable and Low Latency Communication)) that considers services and/or terminals that are sensitive to communication reliability and/or latency is also designed. It is being discussed.

Hereinafter, in this specification, for convenience of explanation, the next-generation wireless access technology may be referred to as New RAT (Radio Access Technology) or by other names. For example, a wireless communication system to which New RAT is applied may be referred to as a NR (New Radio) system. In this specification, frequencies, frames, subframes, resources, resource blocks, regions, bands, subbands, control channels, data channels, synchronization signals, various reference signals, various signals, or various messages related to next-generation wireless access technology It can be interpreted in a variety of meanings that may be used in the past or present, or may be used in the future.

Figure 2 is an exemplary diagram showing an NR system to which a data transmission method according to an embodiment of the present invention can be applied.

NR, a next-generation wireless communication technology under standardization in 3GPP, is a wireless access technology that provides improved data transmission rates compared to LTE and can satisfy various QoS requirements for each segmented and specific usage scenario. . In particular, eMBB (enhanced Mobile BroadBand), mMTC (massive MTC), and URLLC (Ultra Reliable and Low Latency Communications) were defined as representative usage scenarios of NR. As a way to meet the requirements of each scenario, a more flexible frame structure is provided compared to LTE. NR's frame structure supports a frame structure based on multiple subcarriers. The default subcarrier spacing (SCS) is 15kHz, and a total of 5 types of SCS are supported at 15kHz*2^n (n=0, 1, 2, 3, 4).

Referring to Figure 2, NG-RAN (Next Generation-Radio Access Network) terminates the NG-RAN user plane (SDAP/PDCP/RLC/MAC/PHY) and control plane (RRC) protocol for UE (User Equipment). It consists of gNBs provided. Here, NG-C represents the control plane interface used for the NG2 reference point between NG-RAN and 5GC (5 Generation Core). NG-U represents the user plane interface used for the NG3 reference point between NG-RAN and 5GC.

gNBs are interconnected through the Xn interface and to 5GC through the NG interface. More specifically, the gNB is connected to the Access and Mobility Management Function (AMF) through the NG-C interface and to the User Plane Function (UPF) through the NG-U interface.

In the NR system of FIG. 2, multiple numerologies can be supported. Here, the numerology can be defined by subcarrier spacing and CP (Cyclic Prefix) overhead. At this time, multiple subcarrier spacing can be derived by scaling the basic subcarrier spacing to an integer. Additionally, although it is assumed that very low subcarrier spacing is not used at very high carrier frequencies, the numerology used may be selected independently of the frequency band.

Additionally, in the NR system, various frame structures according to multiple numerologies can be supported.

<NR wave form, numerology and frame structure>

In NR, the CP-OFDM waveform using a cyclic prefix is used for downlink transmission, and CP-OFDM or DFT-S-OFDM is used for uplink transmission. OFDM technology is easy to combine with MIMO (Multiple Input Multiple Output) and has the advantage of being able to use a low-complexity receiver with high frequency efficiency.

Meanwhile, in NR, the requirements for data rate, delay rate, coverage, etc. are different for each of the three scenarios described above, so it is necessary to efficiently satisfy the requirements for each scenario through the frequency band that constitutes an arbitrary NR system. . To this end, a technology for efficiently multiplexing wireless resources based on a plurality of different numerologies has been proposed.

Specifically, the NR transmission numerology is determined based on sub-carrier spacing and CP (Cyclic prefix), and as shown in Table 1 below, the μ value is used as an exponent value of 2 based on 15 kHz, resulting in an exponential is changed to

μ Subcarrier spacing
(kHz) Cyclic prefix Supported for data Supported for synchronization 0 15 Normal Yes Yes One 30 Normal Yes Yes 2 60 Normal,Extended Yes No 3 120 Normal Yes Yes 4 240 Normal No Yes

As shown in Table 1 above, NR's numerology can be divided into five types depending on the subcarrier spacing. This is different from the subcarrier spacing of LTE, one of the 4G communication technologies, which is fixed at 15kHz. Specifically, the subcarrier intervals used for data transmission in NR are 15, 30, 60, and 120 kHz, and the subcarrier intervals used for synchronization signal transmission are 15, 30, 120, and 240 kHz. Additionally, the extended CP applies only to the 60kHz subcarrier spacing. Meanwhile, the frame structure in NR is defined as a frame with a length of 10ms consisting of 10 subframes with the same length of 1ms. One frame can be divided into half-frames of 5ms, and each half-frame contains 5 subframes. In the case of 15kHz subcarrier spacing, one subframe consists of 1 slot, and each slot consists of 14 OFDM symbols. <NR physical resource>

Regarding physical resources in NR, antenna port, resource grid, resource element, resource block, bandwidth part, etc. are considered. do.

An antenna port is defined so that a channel carrying a symbol on the antenna port can be inferred from a channel carrying another symbol on the same antenna port. If the large-scale properties of the channel carrying the symbols on one antenna port can be inferred from the channel carrying the symbols on the other antenna port, then the two antenna ports are quasi co-located or QC/QCL. It can be said that they are in a quasi co-location relationship. Here, the wide range characteristics include one or more of delay spread, Doppler spread, Doppler shift, average delay, and spatial Rx parameter.

FIG. 3 is a diagram illustrating a resource grid supported by wireless access technology to which this embodiment can be applied.

Referring to FIG. 3, since NR supports multiple numerology on the same carrier, a resource grid may exist for each numerology. Additionally, resource grids may exist depending on antenna ports, subcarrier spacing, and transmission direction.

A resource block consists of 12 subcarriers and is defined only in the frequency domain. Additionally, a resource element consists of one OFDM symbol and one subcarrier. Therefore, as shown in FIG. 3, the size of one resource block may vary depending on the subcarrier spacing. Additionally, NR defines "Point A", which serves as a common reference point for the resource block grid, common resource blocks, physical resource blocks, etc.

Figure 4 is a diagram for explaining the bandwidth part supported by the wireless access technology to which this embodiment can be applied.

In 5G NR, unlike LTE E-UTRA, where the carrier bandwidth is fixed at 20MHz, the maximum carrier bandwidth is set from 50MHz to 400MHz for each subcarrier interval. Therefore, it is not assumed that all terminals use all of these carrier bandwidths. Accordingly, in NR, the terminal can use a designated bandwidth part (BWP) within the carrier bandwidth as shown in FIG. 4. Additionally, the bandwidth part is linked to one numerology and consists of a subset of consecutive common resource blocks, and can be activated dynamically over time. The terminal is configured with up to four bandwidth parts for each uplink and downlink, and data is transmitted and received using the bandwidth parts activated at a given time.

In the case of a paired spectrum, the uplink and downlink bandwidth parts are set independently, and in the case of an unpaired spectrum, to prevent unnecessary frequency re-tunning between downlink and uplink operations. For this purpose, the bandwidth parts of the downlink and uplink are set in pairs so that they can share the center frequency.

<NR initial access>

In NR, the terminal performs cell search and random access procedures to connect to the base station and perform communication.

Cell search is a procedure in which the terminal synchronizes to the cell of the base station, obtains a physical layer cell ID, and obtains system information using a synchronization signal block (SSB) transmitted by the base station.

Figure 5 is a diagram illustrating a synchronization signal block in a wireless access technology to which this embodiment can be applied.

Referring to Figure 5, the SSB consists of a Primary Synchronization Signal (PSS) and Secondary Synchronization Signal (SSS), each occupying 1 symbol and 127 subcarriers, and a PBCH spanning 3 OFDM symbols and 240 subcarriers. .

The terminal receives the SSB by monitoring the SSB in the time and frequency domains.

SSB can be transmitted up to 64 times in 5ms. Multiple SSBs are transmitted through different transmission beams within 5ms, and the terminal performs detection assuming that SSBs are transmitted every 20ms period based on one specific beam used for transmission. The number of beams that can be used for SSB transmission within 5ms time can increase as the frequency band becomes higher. For example, up to 4 different SSB beams can be transmitted under 3 GHz, up to 8 different beams can be used in the frequency band from 3 to 6 GHz, and up to 64 different beams can be used in the frequency band above 6 GHz.

Two SSBs are included in one slot, and the start symbol and number of repetitions within the slot are determined according to the subcarrier spacing as follows.

Meanwhile, unlike SS in conventional LTE, SSB is not transmitted at the center frequency of the carrier bandwidth. In other words, SSBs can be transmitted even in places other than the center of the system band, and when broadband operation is supported, multiple SSBs can be transmitted in the frequency domain. Accordingly, the terminal monitors the SSB using a synchronization raster, which is a candidate frequency location for monitoring the SSB. The carrier raster and synchronization raster, which are the center frequency location information of the channel for initial access, were newly defined in NR, and the synchronization raster has a wider frequency interval than the carrier raster, supporting fast SSB search of the terminal. You can.

The UE can obtain the MIB through the PBCH of the SSB. MIB (Master Information Block) contains the minimum information necessary for the terminal to receive the remaining minimum system information (RMSI) broadcast by the network. In addition, the PBCH includes information about the location of the first DM-RS symbol in the time domain, information for the terminal to monitor SIB1 (e.g., SIB1 numerology information, information related to SIB1 CORESET, search space information, PDCCH (related parameter information, etc.), offset information between the common resource block and the SSB (the position of the absolute SSB within the carrier is transmitted through SIB1), etc. Here, the SIB1 numerology information is equally applied to some messages used in the random access procedure for accessing the base station after the terminal completes the cell search procedure. For example, numerology information of SIB1 may be applied to at least one of messages 1 to 4 for the random access procedure.

The above-mentioned RMSI may mean SIB1 (System Information Block 1), and SIB1 is broadcast periodically (ex, 160ms) in the cell. SIB1 contains information necessary for the terminal to perform the initial random access procedure and is transmitted periodically through PDSCH. In order for the terminal to receive SIB1, it must receive numerology information used for SIB1 transmission and CORESET (Control Resource Set) information used for scheduling SIB1 through the PBCH. The UE uses SI-RNTI in CORESET to check scheduling information for SIB1 and acquires SIB1 on the PDSCH according to the scheduling information. Except for SIB1, the remaining SIBs may be transmitted periodically or according to the request of the terminal.

Below, small cells are described.

A small cell base station (hereinafter referred to as small cell) refers to a base station that has an area of hundreds to tens of meters using low power rather than the existing wide-area base station that has an area of several kilometers. The Small Cell Forum defines small cells as the range of base stations operated by operators operating in licensed and unlicensed bands. The Small Cell Forum initially classified cells into household femto cells, corporate pico cells, macro cells and micro cells used in urban or rural areas, depending on the size and purpose of the cell, and also categorized by subscriber capacity. Small cells were introduced in the 3rd generation UMTS (Universal Mobile Telecommunication System) to eliminate shadow areas that cannot be accommodated by wide-area base stations, and 4th generation LTE is used as an offload for data traffic in hotspot areas. It dealt with eNB, and was later defined as small cell technology, becoming a candidate technology that can increase transmission capacity through cooperation with wide-area base stations. In 5G, it is defined as the basic mobile communication network structure for capacity increase.

Figure 6 shows an example of a small cell structure.

Referring to Figure 6, gNB, which is a 5G NodeB, is connected to the 5G core network (5GC: 5th Generation Core network) through the NG interface (Next Generation Interface). The small cell structure of 5G gNB includes a traditional gNB and a gNB composed of a Centralized Unit (CU) and Distributed Unit (DU) connected to the F1 interface. Here, CU includes Service Data Adaptation Protocol (SDAP), Packet Data Convergence Protocol (PDCP), and Radio Resource Control (RRC), and DU includes Radio Link Control (RLC), MAC, physical layer, and RF.

5G small cells can be traditional integrated small cells in which all gNB functions are physically implemented in a single device, or they can be small cells with the functions divided into two or three. There are two solutions for a small cell split into two: a separate CU and DU integrated with a RU (Radio Unit), and a CU and DU integrated with a separate RU. A small cell divided into three refers to a solution in which CU, DU, and RU exist separately.

Hereinafter, the proposed methods of this specification are described.

In general, the cell coverage of each macro cell partially overlaps with each other, and the DL resources and UL resources of Time Division Duplex (TDD) allocated to a specific macro cell are the DL resources of TDD allocated to neighboring cells of the specific macro cell. and may be the same as UL resources. When cell coverage overlaps and different DL/UL resource allocation patterns are used for each cell, interference between DL signals and UL signals may occur at the cell edge where coverage overlaps. Therefore, communication quality may deteriorate.

Additionally, in general, the coverage of small cells does not overlap with each other and is often located far apart. In this case, Dynamic TDD, which dynamically sets and uses DL resources and UL resources according to the traffic situation of each cell, can be applied. When each of the small cells operates in Dynamic TDD, and the coverage of the small cells overlaps or the cell edges of the small cells are close to each other, terminals located at the cell edge receive interference signals from the base station or terminal of the adjacent cell. You can receive it.

Figure 7 shows examples where interference occurs for a terminal located at the cell edge. Specifically, Figure 7 (a) shows an example in which a downlink signal received by a second terminal acts as an interference signal for an uplink signal transmitted by the first terminal. In addition, (b) in FIG. 7 shows that when a downlink signal is received by a fourth terminal, the uplink signal transmitted by the third terminal to the base station is transmitted omnidirectionally and interferes with the downlink reception of a nearby fourth terminal. An example of what occurs is shown. Here, at least some of the cells in FIG. 7 may be macro cells or small cells.

Referring to (a) of FIG. 7, the first terminal may transmit an uplink signal to the first base station of the first cell where the first terminal is located. At this time, the second terminal can receive a downlink signal from the second base station of the second cell where it is located. Here, the downlink signal may act as an interference signal for the uplink signal or the first base station. That is, from the perspective of the first base station, the downlink signal transmitted by the second base station may be interference with the uplink signal.

Referring to (b) of FIG. 7, the third terminal can transmit an uplink signal to the third base station through uplink resources. At this time, the fourth terminal can receive a downlink signal from the fourth base station of the fourth cell in which it is located. The uplink signal and the downlink signal may collide with each other.

Additionally, a base station or small cell base station can perform measurements on signals transmitted from other base stations or terminals and determine whether interference has occurred based on the measurements. Here, the measurement may be a measurement of Reference Signal Received Power (RSRP), Signal to Interference plus Noise Ratio (SINR), etc. In addition, the signal may be a reference signal (e.g., Sounding Reference Signal (SRS), Channel Status Information-Reference Signal (CSI-RS), Channel Status Information-Interference Measurements (CSI-IM), etc.), a discovery signal ), SSB (Synchronization Signal Block), or a newly defined signal for interference measurement.

Therefore, to control inter-cell interference, the following methods can be used. The methods described below may be used independently of each other, or may be combined with each other and used simultaneously. In addition, the methods described below are explained based on small cells, but can also be applied to other types of cells (e.g., macro cells, etc.) other than small cells.

(Method 1) A method in which small cells share or transmit TDD resource allocation information between the small cells, so that at the moment a specific small cell transmits important information, the small cells use the same resource allocation pattern for a certain period of time.

(Method 2) Divide frequency resources (e.g., channel bandwidth) into subband types/units, set/allocate different subbands that do not overlap with each other for each small cell, and store important information in the corresponding frequency resources. How to send and receive through.

Hereinafter, in Method 1, small cells share or transmit TDD resource allocation information between the small cells, so that at the moment a specific small cell transmits important information, the small cells follow the same resource allocation pattern for a certain period of time. The method of use is explained in more detail.

If there are no special problems due to interference between cells, each small cell may operate in dynamic TDD, that is, dynamically allocating the ratio of downlink time resources and uplink time resources according to traffic load and interference situations. You can. If interference (i.e., CLI (Cross-Link Interference)) occurs due to a collision between DL resources and UL resources of inter-cell TDD between small cells and the transmission quality deteriorates, adjacent cells must use the same You can use TDD resource allocation patterns.

In other words, each small cell basically operates by dynamically setting TDD resources according to the traffic situation of the cell. Here, in order to solve the problem when cell quality deteriorates due to CLI, a specific TDD resource allocation pattern can be set identically for the small cells for a certain time period. Here, the length of the time section can be set flexibly, for example, to be very long or short, depending on various situations of the cell.

For example, when a terminal located at the cell edge transmits important data, if communication is not performed well due to poor communication quality due to CLI, resource allocation patterns between small cells need to be consistent, at least while transmitting the traffic. For example, each small cell can determine such a situation and, if necessary, perform communication while matching the TDD resource allocation pattern with neighboring cells. Through this, important data can be transmitted with CLI relaxed.

In order to quickly inform other cells of the TDD resource allocation pattern and share the pattern, small cells can define multiple resource allocation patterns in advance and share them in the form of a table. Here, for example, when pattern information is shared between small cells, signaling overhead can be reduced through transmission of index information of the pattern in the table.

For example, the following two methods can be used to share resource allocation patterns between cells.

(1) Centralized method: A method that informs all cells of resource allocation patterns through the OAM (Operation and Management) (or SON (Self-Organizing Network)) system.

According to the above method, small cells can be connected to one OAM system. Here, the central OAM system can inform the TDD resource allocation pattern of each cell and the time that the pattern lasts.

Additionally, one of the small cells may request from the OAM system the TDD resource allocation method desired by the small cell and the time to apply it. Here, the OAM system can determine/set the range and time of the cell to which the TDD resource allocation pattern will be applied based on the application.

Figure 8 shows an example of a small cell system to which a centralized method is applied.

Referring to FIG. 8, there are first to fourth cells, and each of the cells is connected to the OAM system. The OAM system may transmit information about a new TDD resource allocation pattern to the cells. Here, the information may include information about the time at which the pattern is applied. The pattern may be applied to each of the cells that have received the information.

(2) Distributed method: A method in which small cells share resource allocation patterns with each other through interfaces connected to adjacent cells (e.g., X2 interface in LTE, Xn interface in 5G). Here, the method may also include cases where small cells are connected through a higher core network (e.g., MME of LTE, AMF of 5G, etc.).

According to the above method, in a situation where CLI occurs with an adjacent small cell when small cells cannot communicate with each other, the TDD resource allocation pattern of the cell or aggressor cell that generates the interference signal is recognized and then resolved. A method may be used to change the TDD resource allocation pattern in a cell or victim cell damaged by the interference signal and transmit the pattern to cells capable of communicating with the victim cell.

For example, when there are multiple businesses using private 5G networks, the above method can be used if each of the private 5G networks used by the businesses includes a small cell. Here, private 5G is a LAN (Local Area Network) based on 5G technology that integrates 5G technology and other communication technologies and systems to ensure optimized service and safe communication within a specific area. It is a private wireless network. It can mean a type of . In other words, private 5G is an exclusive-purpose private network that can be used only by specific entities, such as companies or universities, by directly building a 5G network or using the facilities of an MNO (Mobile Network Operator). MNOs provide services to the entire population. This is the opposite of public 5G, which anyone can use. Private 5G can be replaced by various terms such as local 5G, 5G LAN (Local Area Network), enterprise 5G, and non-public 5G.

Figure 9 shows an example of a small cell system to which a distributed method is applied.

Referring to FIG. 9, there is a small cell system including first to fourth cells, and another small cell system exists near the small cell system. Here, the attacker cell of the other small cell system may be a source of interference for the first cell of the small cell system. That is, CLI may be generated by the first cell and the attacker cell, and the first cell may be a victim cell.

In this case, the first cell can determine the TDD resource allocation pattern of the attacker cell. The first cell may determine the TDD resource allocation pattern to be used by the first cell based on the determination. Thereafter, the first cell may transmit information about the pattern to the second to fourth cells. The second to fourth cells may use the same TDD resource allocation pattern as the first cell based on the information.

Figure 10 shows an example of a TDD resource allocation pattern.

Referring to FIG. 10, a resource allocation pattern consisting of multiple slots may exist in TDD mode. The length and period of the resource allocation pattern can be set in various ways as needed.

In relation to setting the resource allocation pattern, RRC IE (Information Element) “TDD-UL-DL-ConfigCommon” may be used. The IE may indicate a plurality of patterns, and each of the plurality of patterns may indicate the number of downlink slots, the number of downlink symbols, the number of uplink slots, and the number of uplink symbols. For example, when pattern 3 in FIG. 10 is indicated, two downlink slots, two uplink slots, the number of downlink symbols of pattern 3, and the number of uplink symbols of pattern 3 may be indicated.

Alternatively, multiple TDD resource allocation patterns may be defined in the form of a table. At this time, an index for each of a plurality of TDD resource allocation patterns included in the table may be set/allocated. For example, the resource allocation pattern may be indicated by an RRC message or RRC IE indicating the index. That is, an RRC message or RRC IE for a table of multiple resource allocation patterns may be newly defined.

Hereinafter, method 2, that is, divides frequency resources (e.g., channel bandwidth) into subband types/units, sets/assigns different subbands that do not overlap each other for each small cell, and collects important information. The method of transmitting and receiving through the corresponding frequency resource is explained in more detail.

Figure 11 shows an example in which method 2 is applied.

Referring to FIG. 11, there are first to fourth cells, and each of the cells is connected to the OAM system. Here, the OAM system divides the channel bandwidth into subbands 1 to 4 and may indicate subbands allocated to each of the first to fourth cells. Each of the first to fourth cells can transmit and receive important information on the allocated subband. Here, the important information may include control information, priority, or information with relatively high QoS (Quality of Service) priority.

In particular, from the perspective of a terminal located at the cell edge, if frequency resources are allocated to each small cell as in method 2 above, inter-cell interference occurring at the cell edge can be alleviated.

Each of the small cells may use frequency resources corresponding to the entire channel bandwidth, but each of the small cells may use a specific frequency resource (eg, subband, etc.) as a resource for important data transmission. In this case, priority or priorities for specific frequency resources can be considered to be set for each of the small cells. Therefore, when Method 2 is applied, inter-cell interference may not occur in the specific frequency resource.

Regarding method 2 above, the allocation pattern for a specific frequency resource may not be used continuously. That is, allocation to a specific frequency resource is maintained for a specific time, and when the specific time elapses, each of the small cells may freely use the frequency resource corresponding to the entire channel bandwidth.

Meanwhile, even when dividing subbands, the size of the subbands can be set based on the traffic situation of each cell. For example, if a lot of important data needs to be processed in a specific cell at a specific time, relatively more or larger subband resources may be allocated to the specific cell.

Figure 12 shows another example where Method 2 is applied.

If there are multiple small cells within cell coverage, the corresponding subband allocation pattern may be set as a repetitive pattern in the form of a cluster depending on the location. Referring to FIG. 12, the entire channel bandwidth can be divided into 4 subbands, and then each of the subbands can be allocated to 16 small cells.

Hereinafter, embodiments to which at least some of the methods proposed in this specification are applied will be described. Since it is obvious that various methods proposed in this specification can be additionally applied to embodiments described later, redundant description is omitted.

13 is a flowchart of an example of a method for interference control according to some implementations of the present disclosure. In FIG. 13, each of the first communication device, the second communication device, and the third communication device may be a small cell base station. For example, the second communication device and the third communication device may be communication devices that exist adjacent to the first communication device.

Referring to FIG. 13, the first communication device can determine whether interference has occurred (S1310). Here, the determination of whether the interference occurs may be performed based on measurement of a signal transmitted from another base station or terminal. Here, the measurement may be a measurement of Reference Signal Received Power (RSRP), Signal to Interference plus Noise Ratio (SINR), etc. In addition, the signal may include a reference signal (e.g., Sounding Reference Signal (SRS), Channel Status Information-Reference Signal (CSI-RS), etc.), Channel Status Information-Interference Measurements (CSI-IM), etc.), a discovery signal ( Discovery Signal), Synchronization Signal Block (SSB), or a newly defined signal for interference measurement.

Based on the first communication device determining that interference has occurred, the first communication device may transmit resource allocation information to the second communication device and the third communication device (S1320). Here, the resource allocation information may include information about the TDD resource allocation pattern to be set for the first communication device, that is, information about the allocation of uplink time resources and downlink time resources. Additionally, the resource allocation information may include information about the time at which the TDD resource allocation pattern is applied.

As information about the TDD resource allocation pattern, RRC IE (Information Element) “TDD-UL-DL-ConfigCommon” can be used. The IE may indicate a plurality of patterns, and each of the plurality of patterns may indicate the number of downlink slots, the number of downlink symbols, the number of uplink slots, and the number of uplink symbols. For example, when pattern 3 in FIG. 10 is indicated, two downlink slots, two uplink slots, the number of downlink symbols of pattern 3, and the number of uplink symbols of pattern 3 may be indicated.

Alternatively, a plurality of TDD resource allocation patterns may be defined in the form of a table, and an index for each of the plurality of TDD resource allocation patterns included in the table may be indicated by information about the TDD resource allocation pattern.

Alternatively, the resource allocation information may indicate frequency resources allocated to each of the first communication device, the second communication device, and the third communication device. Here, the frequency resource may be a partial band of the entire channel bandwidth. That is, the first communication device divides the entire channel bandwidth into three bands (or subbands) and allocates each of the three bands to each of the first communication device, the second communication device, and the third communication device. You can. Additionally, the resource allocation information may include information about the time at which the frequency resource is allocated.

The first communication device may perform communication based on the resource allocation information (S1330). At this time, the second communication device and the third communication device may also perform communication based on the resource allocation information.

14 is a flowchart of another example of a method for interference control according to some implementations of the present specification. In Figure 14, the first communication device may be an OAM device (eg, OAM server, etc.). Additionally, each of the second communication device and the third communication device may be a small cell base station. Here, the second communication device and the third communication device may be devices controlled/managed by the first communication device.

Referring to FIG. 14, the first communication device can determine whether to transmit resource allocation information (S1410). Here, the determination may be performed based on a request from the second communication device or the third communication device. For example, the second communication device or the third communication device may transmit request information indicating a request for resource allocation information to the first communication device. Alternatively, the second communication device or the third communication device may determine that interference has occurred and transmit reporting information about the occurrence of the interference to the first communication device. When the first communication device receives the request information or the report information, it can determine transmission of the resource allocation information.

The first communication device may transmit resource allocation information to the second communication device and the third communication device (S1420). The second communication device and the third communication device may perform communication based on the resource allocation information (S1430).

Here, the resource allocation information may include information about a TDD resource allocation pattern to be commonly set for the second communication device and the third communication device, that is, information about the allocation of uplink time resources and downlink time resources. You can. Additionally, the resource allocation information may include information about the time at which the TDD resource allocation pattern is applied.

Alternatively, the resource allocation information may indicate frequency resources allocated to each of the second communication device and the third communication device. Here, the frequency resource may be a partial band of the entire channel bandwidth. That is, the first communication device divides the entire channel bandwidth into two bands (or subbands), allocates one of the two bands to the second communication device, and allocates the other to the third communication device. You can. Additionally, the resource allocation information may include information about the time at which the frequency resource is allocated.

Below, an example of a communication system to which the present invention is applied will be described.

Although not limited thereto, the various descriptions, functions, procedures, suggestions, methods and/or operation flowcharts of the present invention disclosed in this document can be applied to various fields requiring wireless communication/connection (e.g., 5G) between devices. You can.

Hereinafter, a more detailed example will be provided with reference to the drawings. In the following drawings/descriptions, identical reference numerals may illustrate identical or corresponding hardware blocks, software blocks, or functional blocks, unless otherwise noted.

Figure 15 illustrates a communication system 1 applied to the present invention.

Referring to FIG. 15, the communication system 1 applied to the present invention includes a wireless device, a base station, and a network. Here, a wireless device refers to a device that performs communication using wireless access technology (e.g., 5G NR (New RAT), LTE (Long Term Evolution)) and may be referred to as a communication/wireless/5G device. Although not limited thereto, wireless devices include robots (100a), vehicles (100b-1, 100b-2), XR (eXtended Reality) devices (100c), hand-held devices (100d), and home appliances (100e). ), IoT (Internet of Thing) device (100f), and AI device/server (400). For example, vehicles may include vehicles equipped with wireless communication functions, autonomous vehicles, vehicles capable of inter-vehicle communication, etc. Here, the vehicle may include an Unmanned Aerial Vehicle (UAV) (eg, a drone). XR devices include AR (Augmented Reality)/VR (Virtual Reality)/MR (Mixed Reality) devices, HMD (Head-Mounted Device), HUD (Head-Up Display) installed in vehicles, televisions, smartphones, It can be implemented in the form of computers, wearable devices, home appliances, digital signage, vehicles, robots, etc. Portable devices may include smartphones, smart pads, wearable devices (e.g., smartwatches, smart glasses), and computers (e.g., laptops, etc.). Home appliances may include TVs, refrigerators, washing machines, etc. IoT devices may include sensors, smart meters, etc. For example, a base station and network may also be implemented as wireless devices, and a specific wireless device 200a may operate as a base station/network node for other wireless devices.

Here, the wireless communication technology implemented in the wireless device of this specification may include Narrowband Internet of Things for low-power communication as well as LTE, NR, and 6G. At this time, for example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology and may be implemented in standards such as LTE Cat NB1 and/or LTE Cat NB2, and is limited to the above-mentioned names. no. Additionally or alternatively, the wireless communication technology implemented in the wireless device of the present specification may perform communication based on LTE-M technology. At this time, as an example, LTE-M technology may be an example of LPWAN technology, and may be called various names such as enhanced Machine Type Communication (eMTC). For example, LTE-M technologies include 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine. It can be implemented in at least one of various standards such as Type Communication, and/or 7) LTE M, and is not limited to the above-mentioned names. Additionally or alternatively, the wireless communication technology implemented in the wireless device of the present specification may include at least one of ZigBee, Bluetooth, and Low Power Wide Area Network (LPWAN) considering low-power communication. It is possible, and is not limited to the above-mentioned names. As an example, ZigBee technology can create personal area networks (PAN) related to small/low-power digital communications based on various standards such as IEEE 802.15.4, and can be called by various names.

Wireless devices 100a to 100f may be connected to the network 300 through the base station 200. AI (Artificial Intelligence) technology may be applied to wireless devices (100a to 100f), and the wireless devices (100a to 100f) may be connected to the AI server 400 through the network 300. The network 300 may be configured using a 3G network, 4G (eg, LTE) network, or 5G (eg, NR) network. Wireless devices 100a to 100f may communicate with each other through the base station 200/network 300, but may also communicate directly (e.g. sidelink communication) without going through the base station/network. For example, vehicles 100b-1 and 100b-2 may communicate directly (e.g. V2V (Vehicle to Vehicle)/V2X (Vehicle to everything) communication). Additionally, an IoT device (eg, sensor) may communicate directly with another IoT device (eg, sensor) or another wireless device (100a to 100f).

Wireless communication/connection (150a, 150b, 150c) may be established between the wireless devices (100a to 100f)/base station (200) and the base station (200)/base station (200). Here, wireless communication/connection includes various wireless connections such as uplink/downlink communication (150a), sidelink communication (150b) (or D2D communication), and inter-base station communication (150c) (e.g. relay, IAB (Integrated Access Backhaul)). This can be achieved through technology (e.g., 5G NR) through wireless communication/connection (150a, 150b, 150c), where a wireless device and a base station/wireless device, and a base station and a base station can transmit/receive wireless signals to each other. For example, wireless communication/connection 150a, 150b, and 150c can transmit/receive signals through various physical channels, based on various proposals of the present invention. At least some of various configuration information setting processes, various signal processing processes (e.g., channel encoding/decoding, modulation/demodulation, resource mapping/demapping, etc.), resource allocation processes, etc. may be performed.

Figure 16 illustrates a wireless device to which the present invention can be applied.

Referring to FIG. 16, the first wireless device 100 and the second wireless device 200 can transmit and receive wireless signals through various wireless access technologies (eg, LTE, NR). Here, {first wireless device 100, second wireless device 200} refers to {wireless device 100x, base station 200} and/or {wireless device 100x, wireless device 100x) in FIG. 15. } can be responded to.

The first wireless device 100 includes one or more processors 102 and one or more memories 104, and may additionally include one or more transceivers 106 and/or one or more antennas 108. Processor 102 controls memory 104 and/or transceiver 106 and may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed herein. For example, the processor 102 may process information in the memory 104 to generate first information/signal and then transmit a wireless signal including the first information/signal through the transceiver 106. Additionally, the processor 102 may receive a wireless signal including the second information/signal through the transceiver 106 and then store information obtained from signal processing of the second information/signal in the memory 104. The memory 104 may be connected to the processor 102 and may store various information related to the operation of the processor 102. For example, memory 104 may perform some or all of the processes controlled by processor 102 or may be used to perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed herein. Software code containing instructions can be stored. Here, the processor 102 and memory 104 may be part of a communication modem/circuit/chip designed to implement wireless communication technology (eg, LTE, NR). Transceiver 106 may be coupled to processor 102 and may transmit and/or receive wireless signals via one or more antennas 108. Transceiver 106 may include a transmitter and/or receiver. The transceiver 106 can be used interchangeably with an RF (Radio Frequency) unit. In the present invention, a wireless device may mean a communication modem/circuit/chip.

The second wireless device 200 includes one or more processors 202, one or more memories 204, and may further include one or more transceivers 206 and/or one or more antennas 208. Processor 202 controls memory 204 and/or transceiver 206 and may be configured to implement the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed herein. For example, the processor 202 may process the information in the memory 204 to generate third information/signal and then transmit a wireless signal including the third information/signal through the transceiver 206. Additionally, the processor 202 may receive a wireless signal including the fourth information/signal through the transceiver 206 and then store information obtained from signal processing of the fourth information/signal in the memory 204. The memory 204 may be connected to the processor 202 and may store various information related to the operation of the processor 202. For example, memory 204 may perform some or all of the processes controlled by processor 202 or may be used to perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed herein. Software code containing instructions can be stored. Here, the processor 202 and memory 204 may be part of a communication modem/circuit/chip designed to implement wireless communication technology (eg, LTE, NR). Transceiver 206 may be coupled to processor 202 and may transmit and/or receive wireless signals via one or more antennas 208. Transceiver 206 may include a transmitter and/or receiver. Transceiver 206 may be used interchangeably with an RF unit. In the present invention, a wireless device may mean a communication modem/circuit/chip.

Hereinafter, the hardware elements of the wireless devices 100 and 200 will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors 102, 202. For example, one or more processors 102, 202 may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, SDAP). One or more processors 102, 202 may operate one or more Protocol Data Units (PDUs) and/or one or more Service Data Units (SDUs) according to the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed herein. can be created. One or more processors 102, 202 may generate messages, control information, data or information according to the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed herein. One or more processors (102, 202) generate signals (e.g., baseband signals) containing PDUs, SDUs, messages, control information, data or information according to the functions, procedures, suggestions and/or methods disclosed herein. Thus, it can be provided to one or more transceivers (106, 206). One or more processors (102, 202) may receive signals (e.g., baseband signals) from one or more transceivers (106, 206) and the descriptions, functions, procedures, suggestions, methods and/or operations disclosed herein. PDU, SDU, message, control information, data or information can be obtained according to the flowcharts.

One or more processors 102, 202 may be referred to as a controller, microcontroller, microprocessor, or microcomputer. One or more processors 102, 202 may be implemented by hardware, firmware, software, or a combination thereof. As an example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), or one or more Field Programmable Gate Arrays (FPGAs) May be included in one or more processors 102 and 202. The descriptions, functions, procedures, suggestions, methods and/or operational flowcharts invented in this document may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. Firmware or software configured to perform the descriptions, functions, procedures, suggestions, methods and/or operational flowcharts disclosed herein may be included in one or more processors (102, 202) or stored in one or more memories (104, 204). It may be driven by one or more processors 102 and 202. The descriptions, functions, procedures, suggestions, methods and/or operational flowcharts invented in this document may be implemented using firmware or software in the form of codes, instructions and/or sets of instructions.

One or more memories 104, 204 may be connected to one or more processors 102, 202 and may store various types of data, signals, messages, information, programs, codes, instructions, and/or instructions. One or more memories 104, 204 may consist of ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer readable storage media, and/or combinations thereof. One or more memories 104, 204 may be located internal to and/or external to one or more processors 102, 202. Additionally, one or more memories 104, 204 may be connected to one or more processors 102, 202 through various technologies, such as wired or wireless connections.

One or more transceivers 106, 206 may transmit user data, control information, wireless signals/channels, etc. mentioned in the methods and/or operation flowcharts of this document to one or more other devices. One or more transceivers (106, 206) may receive user data, control information, wireless signals/channels, etc. referred to in the descriptions, functions, procedures, suggestions, methods and/or operational flow charts, etc. disclosed herein from one or more other devices. You can. For example, one or more transceivers 106 and 206 may be connected to one or more processors 102 and 202 and may transmit and receive wireless signals. For example, one or more processors 102, 202 may control one or more transceivers 106, 206 to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors 102, 202 may control one or more transceivers 106, 206 to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers (106, 206) may be connected to one or more antennas (108, 208), and one or more transceivers (106, 206) may be coupled to one or more antennas (108, 208). It may be set to transmit and receive user data, control information, wireless signals/channels, etc. mentioned in functions, procedures, suggestions, methods and/or operation flow charts, etc. In this document, one or more antennas may be multiple physical antennas or multiple logical antennas (eg, antenna ports). One or more transceivers (106, 206) process the received user data, control information, wireless signals/channels, etc. using one or more processors (102, 202), and convert the received wireless signals/channels, etc. from the RF band signal. It can be converted to a baseband signal. One or more transceivers (106, 206) may convert user data, control information, wireless signals/channels, etc. processed using one or more processors (102, 202) from baseband signals to RF band signals. For this purpose, one or more transceivers 106, 206 may comprise (analog) oscillators and/or filters.

Figure 17 illustrates a process for generating a transmission signal in a transmitter.

Referring to FIG. 17, the signal processing circuit 1000 may include a scrambler 1010, a modulator 1020, a layer mapper 1030, a precoder 1040, a resource mapper 1050, and a signal generator 1060. there is. Although not limited thereto, the operations/functions of Figure 17 may be performed in the processors 102, 202 and/or transceivers 106, 206 of Figure 16. The hardware elements of Figure 17 may be implemented in the processors 102, 202 and/or transceivers 106, 206 of Figure 16. For example, blocks 1010 to 1060 may be implemented in processors 102 and 202 of FIG. 16 . Additionally, blocks 1010 to 1050 may be implemented in the processors 102 and 202 of FIG. 16, and block 1060 may be implemented in the transceivers 106 and 206 of FIG. 16.

The codeword can be converted into a wireless signal through the signal processing circuit 1000 of FIG. 17. Here, a codeword is an encoded bit sequence of an information block. The information block may include a transport block (eg, UL-SCH transport block, DL-SCH transport block). Wireless signals may be transmitted through various physical channels (eg, PUSCH, PDSCH).

Specifically, the codeword may be converted into a scrambled bit sequence by the scrambler 1010. The scramble sequence used for scrambling is generated based on an initialization value, and the initialization value may include ID information of the wireless device. The scrambled bit sequence may be modulated into a modulation symbol sequence by the modulator 1020. Modulation methods may include pi/2-BPSK (pi/2-Binary Phase Shift Keying), m-PSK (m-Phase Shift Keying), m-QAM (m-Quadrature Amplitude Modulation), etc. The complex modulation symbol sequence may be mapped to one or more transport layers by the layer mapper 1030. The modulation symbols of each transport layer may be mapped to the corresponding antenna port(s) by the precoder 1040 (precoding). The output z of the precoder 1040 can be obtained by multiplying the output y of the layer mapper 1030 with the precoding matrix W of N*M. Here, N is the number of antenna ports and M is the number of transport layers. Here, the precoder 1040 may perform precoding after performing transform precoding (eg, DFT transformation) on complex modulation symbols. Additionally, the precoder 1040 may perform precoding without performing transform precoding.

The resource mapper 1050 can map the modulation symbols of each antenna port to time-frequency resources. A time-frequency resource may include a plurality of symbols (e.g., CP-OFDM symbol, DFT-s-OFDM symbol) in the time domain and a plurality of subcarriers in the frequency domain. The signal generator 1060 generates a wireless signal from the mapped modulation symbols, and the generated wireless signal can be transmitted to another device through each antenna. For this purpose, the signal generator 1060 may include an Inverse Fast Fourier Transform (IFFT) module, a Cyclic Prefix (CP) inserter, a Digital-to-Analog Converter (DAC), a frequency uplink converter, etc. .

The signal processing process for the received signal in the wireless device may be configured as the reverse of the signal processing process (1010 to 1060) of FIG. 17. For example, a wireless device (eg, 100 and 200 in FIG. 16) may receive a wireless signal from the outside through an antenna port/transceiver. The received wireless signal can be converted into a baseband signal through a signal restorer. To this end, the signal restorer may include a frequency downlink converter, an analog-to-digital converter (ADC), a CP remover, and a Fast Fourier Transform (FFT) module. Afterwards, the baseband signal can be restored to a codeword through a resource de-mapper process, postcoding process, demodulation process, and de-scramble process. The codeword can be restored to the original information block through decoding. Accordingly, a signal processing circuit (not shown) for a received signal may include a signal restorer, resource de-mapper, postcoder, demodulator, de-scrambler, and decoder.

Figure 18 shows another example of a wireless device applied to the present invention. Wireless devices can be implemented in various forms depending on usage-examples/services.

Referring to FIG. 18, the wireless devices 100 and 200 correspond to the wireless devices 100 and 200 of FIG. 16 and include various elements, components, units/units, and/or modules. ) can be composed of. For example, the wireless devices 100 and 200 may include a communication unit 110, a control unit 120, a memory unit 130, and an additional element 140. The communication unit may include communication circuitry 112 and transceiver(s) 114. For example, communication circuitry 112 may include one or more processors 102,202 and/or one or more memories 104,204 of FIG. 16. For example, transceiver(s) 114 may include one or more transceivers 106, 206 and/or one or more antennas 108, 208 of FIG. 16. The control unit 120 is electrically connected to the communication unit 110, the memory unit 130, and the additional element 140 and controls overall operations of the wireless device. For example, the control unit 120 may control the electrical/mechanical operation of the wireless device based on the program/code/command/information stored in the memory unit 130. In addition, the control unit 120 transmits the information stored in the memory unit 130 to the outside (e.g., another communication device) through the communication unit 110 through a wireless/wired interface, or to the outside (e.g., other communication devices) through the communication unit 110. Information received through a wireless/wired interface from another communication device may be stored in the memory unit 130.

The additional element 140 may be configured in various ways depending on the type of wireless device. For example, the additional element 140 may include at least one of a power unit/battery, an input/output unit (I/O unit), a driving unit, and a computing unit. Although not limited thereto, wireless devices include robots (FIG. 15, 100a), vehicles (FIG. 15, 100b-1, 100b-2), XR devices (FIG. 15, 100c), portable devices (FIG. 15, 100d), and home appliances. (FIG. 15, 100e), IoT device (FIG. 15, 100f), digital broadcasting terminal, hologram device, public safety device, MTC device, medical device, fintech device (or financial device), security device, climate/environment device, It can be implemented in the form of an AI server/device (FIG. 15, 400), a base station (FIG. 15, 200), a network node, etc. Wireless devices can be mobile or used in fixed locations depending on the usage/service.

In FIG. 18 , various elements, components, units/parts, and/or modules within the wireless devices 100 and 200 may be entirely interconnected through a wired interface, or at least a portion may be wirelessly connected through the communication unit 110. For example, within the wireless devices 100 and 200, the control unit 120 and the communication unit 110 are connected by wire, and the control unit 120 and the first unit (e.g., 130 and 140) are connected through the communication unit 110. Can be connected wirelessly. Additionally, each element, component, unit/part, and/or module within the wireless devices 100 and 200 may further include one or more elements. For example, the control unit 120 may be comprised of one or more processor sets. For example, the control unit 120 may be comprised of a communication control processor, an application processor, an electronic control unit (ECU), a graphics processing processor, and a memory control processor. As another example, the memory unit 130 includes random access memory (RAM), dynamic RAM (DRAM), read only memory (ROM), flash memory, volatile memory, and non-volatile memory. volatile memory) and/or a combination thereof.

The claims set forth herein may be combined in various ways. For example, the technical features of the method claims of this specification may be combined to implement a device, and the technical features of the device claims of this specification may be combined to implement a method. Additionally, the technical features of the method claims of this specification and the technical features of the device claims may be combined to implement a device, and the technical features of the method claims of this specification and technical features of the device claims may be combined to implement a method.

Claims (20)

In a method performed by a base station in a wireless communication system,
determine Time Division Duplex (TDD) resource allocation information; and
Communication is performed based on the TDD resource allocation information,
The TDD resource allocation information indicates at least one of a resource allocation pattern used by the base station and a specific subband used by the base station,
The resource allocation pattern is commonly used by a plurality of base stations including the base station,
The method wherein the specific subband is one of a plurality of subbands divided into channel bandwidths used by the plurality of base stations. According to paragraph 1,
The method wherein the resource allocation pattern is commonly used during a specific time period by a plurality of base stations including the base station. According to paragraph 1,
The TDD resource allocation information is information shared between the plurality of base stations, and
The method wherein the resource allocation pattern is indicated using an index corresponding to one of a plurality of predetermined resource allocation patterns. According to paragraph 1,
The method wherein the subbands used by each of the plurality of base stations do not overlap each other. According to paragraph 1,
The base station performs communication on information of high importance using the specific subband. According to paragraph 1,
Each of the plurality of subbands is used by the plurality of base stations during a specific time period. According to paragraph 1,
The TDD resource allocation information is determined based on the base station determining that interference occurs. According to paragraph 1,
The base station is a base station that provides a small cell. The base station is,
One or more memories storing instructions;
One or more transceivers; and
Includes one or more processors connecting the one or more memories and the one or more transceivers, wherein the one or more processors execute the instructions,
determine Time Division Duplex (TDD) resource allocation information; and
Communication is performed based on the TDD resource allocation information,
The TDD resource allocation information indicates at least one of a resource allocation pattern used by the base station and a specific subband used by the base station,
The resource allocation pattern is commonly used by a plurality of base stations including the base station,
The specific subband is one of a plurality of subbands divided into channel bandwidths used by the plurality of base stations. According to clause 9,
The resource allocation pattern is commonly used during a specific time period by a plurality of base stations including the base station. According to clause 9,
The TDD resource allocation information is information shared between the plurality of base stations, and
The resource allocation pattern is indicated using an index corresponding to one of a plurality of predetermined resource allocation patterns. According to clause 9,
The subbands used by each of the plurality of base stations do not overlap each other. According to clause 9,
The base station performs communication on information of high importance using the specific subband. According to clause 9,
Each of the plurality of subbands is used by the plurality of base stations during a specific time period. According to clause 9,
The TDD resource allocation information is determined based on the base station determining that interference occurs. According to clause 9,
The base station is a base station that provides a small cell. At least one computer readable medium containing instructions based on execution by at least one processor included in a communication device, the instructions being:
determine Time Division Duplex (TDD) resource allocation information; and
Configured to perform communication based on the TDD resource allocation information,
The TDD resource allocation information indicates at least one of a resource allocation pattern used by the communication device and a specific subband used by the communication device,
The resource allocation pattern is commonly used by a plurality of communication devices including the communication device,
The specific subband is one of a plurality of subbands divided into channel bandwidths used by the plurality of communication devices. According to clause 17,
The resource allocation pattern is commonly used during a specific time period by a plurality of communication devices including the communication device. According to clause 17,
The TDD resource allocation information is information shared between the plurality of communication devices, and
A recording medium, wherein the resource allocation pattern is indicated using an index corresponding to one of a plurality of predetermined resource allocation patterns. According to clause 17,
A recording medium wherein subbands used by each of the plurality of communication devices do not overlap each other.

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