WO2022186230A1 - Terminal device and base station device - Google Patents

Abstract

Provided is a terminal device which performs transmission to a base station device, the terminal device comprising: an upper layer processing unit which receives, from the base station device, an upper layer signaling including two parameters of a repeating unit and the number of repetitions; a control unit which, by using the upper layer signaling and a prescribed field included in downlink control information, switches between first transmission that performs repetitive transmission using the two parameters and second transmission that transmits one transport block by using a wireless resource allocated by the two parameters; and a multiplexing unit which switches between DMRS arrangement related to the first transmission and DMRS arrangement related to the second transmission by means of the prescribed field included in the downlink control information.

Description

Terminal equipment and base station equipment

The present invention relates to terminal devices and base station devices. This application claims priority based on Japanese Patent Application No. 2021-34379 filed in Japan on March 4, 2021, the contents of which are incorporated herein.

In the NR (New Radio) communication system specified by 3GPP (Third Generation Partnership Project), one or more demodulation reference signals (DMRS ; Demodulation Reference Signal) is inserted into OFDM symbols. A receiver that receives the transmitted slot performs channel estimation using the DMRS in the slot and demodulates the data signal in the slot.

In addition, NR Release 15 specifies inter-slot repetition transmission in order to improve communication reliability and expand coverage. Inter-slot repetition allows the same data to be repeatedly transmitted in multiple slots. However, since multiple slots are required for repeated transmission, there is a problem in terms of delay. Therefore, in NR Release 16, intra-slot repeat transmission is specified. In intra-slot repetition transmission, it is possible to set a repetition unit multiple times in a slot and perform transmission.

In the specifications up to Rel-16, the DMRS that can be used for channel estimation is limited to within a repetition unit or within a slot. Accuracy can be greatly improved. Therefore, in NR Release 17, joint channel estimation (DMRS bundling, also called DMRS sharing) is being considered, which makes it possible to use DMRSs included in different repetition units or different slots. (Non-Patent Document 1)

Up to Release 16, it was necessary to allocate DMRS for each slot or repetition. However, when channel estimation is performed using DMRS in different slots or different repetitions, considering multiple slots or repetitions, the time resource of DMRS symbols is reduced. There is a problem that a bias occurs in the arrangement of . Therefore, Non-Patent Document 2 proposes that when joint channel estimation is applied, DMRSs are rearranged so that they are evenly spaced in a plurality of allocated slots or a plurality of repeated time resources.

By the way, repeated transmission is an important technique for realizing low delay because data can be decoded for each repeated transmission, and error judgment can be made during repeated transmission. However, considering the entire repeated transmission, transmission characteristics can be improved more by lowering the coding rate than by repeating transmission. Therefore, it is conceivable to transmit one TB (transport block) using a plurality of slots. Non-Patent Document 3 proposes switching between repeated transmission and single TB transmission by dynamic signaling. As a result, repeated transmission can be applied to secure a low delay, and batch encoding transmission of 1 TB can be performed to improve transmission characteristics, making it possible to perform control according to QoS.

In Non-Patent Document 2, when performing joint channel estimation, by rearranging DMRSs (arranging DMRSs at equal intervals in time resources), the rearranged terminal device can obtain good transmission characteristics. However, since the DMRS allocation pattern changes from that of users who are not rearranged, it becomes difficult to apply multi-user MIMO (Multiple Input Multiple Output).

One aspect of the present invention has been made in view of such circumstances, and its purpose is to efficiently expand coverage by enabling effective application of joint channel estimation.

The configurations of the base station apparatus, the terminal apparatus, and the communication method according to one aspect of the present invention to solve the above-described problems are as follows.

(1) One aspect of the present invention is a terminal device that transmits to a base station device, the upper layer receiving higher layer signaling including two parameters of a repetition unit and a repetition number from the base station device. Using the processing unit, the higher layer signaling, and a predetermined field included in downlink control information, a first transmission that performs repeated transmission using the two parameters, and the radio allocated by the two parameters A controller for switching a second transmission that transmits one transport block using resources; a multiplexer for switching between DMRS constellations associated with the transmission of the .
(2) In one aspect of the present invention, the multiplexing unit arranges at least one reference signal for each repetition during DMRS arrangement related to the first transmission, and At the time of DMRS allocation, at least one reference signal is allocated to the radio resources allocated by the two parameters.
(3) In one aspect of the present invention, when performing DMRS allocation related to the second transmission, the multiplexing unit divides the radio resources allocated by the two parameters into 14 symbols, and A DMRS is arranged at a predetermined position of the symbol.
(4) One aspect of the present invention is a base station apparatus that receives a signal transmitted by a terminal apparatus, and an upper layer that generates higher layer signaling including two parameters of a repetition unit and a repetition number for the terminal apparatus. Using a processing unit and a predetermined field included in downlink control information, a first transmission that performs repeated transmission using the two parameters, and one using the radio resource allocated by the two parameters a second transmission switching for transmitting transport blocks, and a downlink control signal section for notifying switching between the DMRS allocation related to the first transmission and the DMRS allocation related to the second transmission; Prepare.
(5) In one aspect of the present invention, the downlink control signal unit arranges at least one reference signal for each repetition when arranging DMRS related to the first transmission, and performs the second transmission. during DMRS configuration associated with , it is indicated to configure at least one reference signal on the radio resources allocated according to the two parameters.
(6) In one aspect of the present invention, the downlink control signal unit divides the radio resources allocated by the two parameters into every 14 symbols when performing the DMRS arrangement related to the second transmission, A DMRS is arranged at a predetermined position of the divided symbols.

According to one or more aspects of the present invention, it is possible to improve system throughput and expand communication coverage.

It is a figure which shows the structural example of the communication system 1 which concerns on this embodiment. It is a figure which shows the structural example of the base station apparatus which concerns on this embodiment. It is a figure which shows the structural example of the terminal device which concerns on this embodiment. FIG. 4 is a diagram showing an example of smart DMRS deployment according to the first embodiment; FIG. 4 is a diagram showing an example of DMRS allocation in repeated transmission and one transport block transmission according to the first embodiment; FIG. 4 is a diagram showing an example of the relationship between the number of symbols and DMRS positions according to the first embodiment; FIG. 10 is a diagram showing another example of DMRS allocation in repeated transmission and one transport block transmission according to the first embodiment; FIG. 10 is a diagram showing a conventional example of use of radio resources in repeated transmission according to the second embodiment; FIG. 10 is a diagram showing an example of use of radio resources in repeated transmission (DMRS transmission) according to the second embodiment; FIG. 10 is a diagram showing an example of use of radio resources (data transmission) in repeated transmission according to the second embodiment; FIG. 10 is a diagram showing a table used for determining transport block sizes of 3824 or less;

The communication system according to this embodiment includes base station devices (cells, small cells, serving cells, component carriers, eNodeB, Home eNodeB, gNodeB) and terminal devices (terminals, mobile terminals, UE: User Equipment). In the communication system, in the case of the downlink, the base station device becomes a transmitting device (transmitting point, transmitting antenna group, transmitting antenna port group, TRP (Tx/Rx Point)), and the terminal device becomes a receiving device (receiving point, receiving terminal , receiving antenna group, receiving antenna port group). In the case of uplink, the base station apparatus becomes a receiving apparatus, and the terminal apparatus becomes a transmitting apparatus. The communication system is also applicable to D2D (Device-to-Device, sidelink) communication. In that case, both the transmitting device and the receiving device are terminal devices.

The communication system is not limited to data communication between a terminal device and a base station device with human intervention. In other words, human intervention such as MTC (Machine Type Communication), M2M communication (Machine-to-Machine Communication), IoT (Internet of Things) communication, NB-IoT (Narrow Band-IoT), etc. (hereinafter referred to as MTC) It can also be applied to a form of data communication that does not require In this case, the terminal device is the MTC terminal. The communication system can use a multicarrier transmission scheme such as CP-OFDM (Cyclic Prefix-Orthogonal Frequency Division Multiplexing) in uplink and downlink. In the uplink, the communication system applies Transform precoding, that is, DFTS-OFDM (Discrete Fourier Transform Spread-Orthogonal Frequency Division Multiplexing, also called SC-FDMA) that applies DFT when upper layer parameters for Transform precoder are set. is used). In addition, although the case where the OFDM transmission method is used in the uplink and the downlink will be described below, the present invention is not limited to this, and other transmission methods can be applied.

The base station device and the terminal device in this embodiment are frequency bands called so-called licensed bands, which are licensed from countries and regions where wireless operators provide services, and / or It is possible to communicate in a frequency band called an unlicensed band, which does not require a permit (license) from a country or region.

In this embodiment, "X/Y" includes the meaning of "X or Y". In this embodiment, "X/Y" includes the meaning of "X and Y." In this embodiment, "X/Y" includes the meaning of "X and/or Y".

(First embodiment)
FIG. 1 is a diagram showing a configuration example of a communication system 1 according to this embodiment. A communication system 1 in this embodiment includes a base station apparatus 10 and a terminal apparatus 20 . The coverage 10a is a range (communication area) in which the base station apparatus 10 can connect (communicate) with the terminal apparatus 20 (also called a cell). Note that the base station apparatus 10 can accommodate a plurality of terminal apparatuses 20 in the coverage 10a.

In FIG. 1, the uplink radio communication r30 includes at least the following uplink physical channels. Uplink physical channels are used to transmit information output from higher layers.
- Physical uplink control channel (PUCCH)
- Physical uplink shared channel (PUSCH)
- Physical Random Access Channel (PRACH)

PUCCH is a physical channel used to transmit uplink control information (UCI). The uplink control information includes positive acknowledgment (ACK)/negative acknowledgment (NACK) for downlink data. Downlink data here refers to Downlink transport block, Medium Access Control Protocol Data Unit: MAC PDU, Downlink-Shared Channel: DL-SCH, Physical Downlink Shared Channel: PDSCH, and the like. ACK/NACK is also called HARQ-ACK (Hybrid Automatic Repeat request ACKnowledgement), HARQ feedback, HARQ response, HARQ control information, or a signal indicating acknowledgment.

NR supports at least five formats: PUCCH format 0, PUCCH format 1, PUCCH format 2, PUCCH format 3, and PUCCH format 4. PUCCH format 0 and PUCCH format 2 are composed of 1 or 2 OFDM symbols, and other PUCCHs are composed of 4 to 14 OFDM symbols. It is also composed of PUCCH format 0 and PUCCH format 1 bandwidth 12 subcarriers. In addition, in PUCCH format 0, 1-bit (or 2-bit) ACK/NACK is transmitted using resource elements of 12 subcarriers and 1 OFDM symbol (or 2 OFDM symbols).

The uplink control information includes a scheduling request (SR) used to request PUSCH (Uplink-Shared Channel: UL-SCH) resources for initial transmission. A scheduling request indicates a request for UL-SCH resources for initial transmission.

The uplink control information includes downlink channel state information (Channel State Information: CSI). The downlink channel state information includes a rank indicator (RI) indicating a preferred spatial multiplexing number (number of layers), a precoding matrix indicator (PMI) indicating a preferred precoder, and a preferred transmission rate. including Channel Quality Indicator (CQI), etc. The PMI indicates a codebook determined by the terminal. The codebook relates to precoding of physical downlink shared channels.

In NR, a higher layer parameter RI limit can be set. The RI limit has multiple setting parameters, one of which is the type 1 single panel RI limit, which consists of 8 bits. Bitmap parameters, type 1 single-panel RI restrictions, form bit sequences r ₇ , . . . r ₂ , r ₁ . Here, r ₇ is the MSB (Most Significant Bit) and r ₀ is the LSB (Least Significant Bit). When r _i is zero (i is 0, 1, . . . 7), PMI and RI reporting corresponding to the precoder associated with layer i+1 is not allowed. RI restrictions include type 1 single panel RI restrictions and type 1 multi-panel RI restrictions, which consist of 4 bits. The type 1 multi-panel RI restriction bitmap parameters form the bit sequence r ₄ , r ₃ , r ₂ , r ₁ . where r ₄ is the MSB and r ₀ is the LSB. When r _i is zero (where i is 0, 1, 2, 3), PMI and RI reporting corresponding to the precoder associated with layer i+1 is not allowed.

The CQI can use a suitable modulation scheme (eg, QPSK, 16QAM, 64QAM, 256QAMAM, etc.) in a predetermined band, a coding rate, and an index (CQI index) indicating frequency utilization efficiency. The terminal device selects from the CQI table a CQI index that would allow PDSCH transport blocks to be received without exceeding block error probability (BLER)=0.1. However, when a predetermined CQI table is set by higher layer signaling, a CQI index that can be received without exceeding BLER=0.00001 is selected from the CQI table.

PUSCH is a physical channel used to transmit uplink data (Uplink Transport Block, Uplink-Shared Channel: UL-SCH), and as a transmission method, CP-OFDM or DFT-S-OFDM is applied. be. PUSCH may be used to transmit control information such as HARQ-ACK and/or channel state information for downlink data along with the uplink data. PUSCH may be used to transmit channel state information only. PUSCH may be used to transmit HARQ-ACK and channel state information only.

PUSCH is used to transmit Radio Resource Control (RRC) signaling. RRC signaling is also referred to as RRC message/RRC layer information/RRC layer signaling/RRC layer parameters/RRC information element. RRC signaling is information/signals processed in the radio resource control layer. The RRC signaling transmitted from the base station apparatus may be signaling common to multiple terminal apparatuses within a cell. The RRC signaling transmitted from the base station apparatus may be dedicated signaling (also referred to as dedicated signaling) for a certain terminal apparatus. That is, user equipment specific information is sent to a terminal using dedicated signaling. The RRC message can include UE Capabilities of the terminal device. UE Capability is information indicating the functions supported by the terminal device.

PUSCH is used to transmit MAC CE (Medium Access Control Element). MAC CE is information/signals processed (transmitted) in the Medium Access Control layer. For example, power headroom may be included in MAC CE and reported via PUSCH. That is, the MAC CE field is used to indicate the level of power headroom. RRC signaling and/or MAC CE are also referred to as higher layer signaling. RRC signaling and/or MAC CE are included in the transport block.

The PRACH is used to transmit preambles used for random access. PRACH is used to transmit a random access preamble. PRACH is used to indicate initial connection establishment procedures, handover procedures, connection re-establishment procedures, synchronization (timing adjustment) for uplink transmissions, and PUSCH (UL-SCH) resource requirements. used for

In uplink wireless communication, an uplink reference signal (Uplink Reference Signal: UL RS) is used as an uplink physical signal. The uplink reference signal includes a demodulation reference signal (DMRS), a sounding reference signal (SRS), a phase tracking signal (PTRS), and the like. DMRS relates to transmission of physical uplink shared channel/physical uplink control channel. For example, when the base station apparatus 10 demodulates the physical uplink shared channel/physical uplink control channel, the demodulation reference signal is used to perform channel estimation/channel correction.

The SRS is not related to the transmission of the physical uplink shared channel/physical uplink control channel. The base station apparatus 10 uses SRS to measure uplink channel conditions (CSI measurement).

The PTRS is related to transmission of the physical uplink shared channel/physical uplink control channel. The base station apparatus 10 uses PTRS for phase tracking.

In FIG. 1, at least the following downlink physical channels are used in downlink r31 radio communication. Downlink physical channels are used to transmit information output from higher layers.
- Physical broadcast channel (PBCH)
- Physical downlink control channel (PDCCH)
- Physical downlink shared channel (PDSCH)

The PBCH is used to broadcast a master information block (Master Information Block: MIB, Broadcast Channel: BCH) commonly used by terminal devices. MIB is one of the system information. For example, the MIB contains the downlink transmission bandwidth setting, System Frame number (SFN). The MIB may contain information indicating at least part of the slot number, subframe number, and radio frame number in which the PBCH is transmitted.

The PDCCH is used to transmit downlink control information (DCI). For downlink control information, a plurality of formats (also called DCI formats) are defined based on usage. A DCI format may be defined based on the type and number of bits of DCI that constitute one DCI format. Each format is used according to its purpose. Downlink control information includes control information for downlink data transmission and control information for uplink data transmission. A DCI format for downlink data transmission is also called a downlink assignment (or downlink grant). A DCI format for uplink data transmission is also called an uplink grant (or uplink assignment).

One downlink assignment is used for scheduling one PDSCH in one serving cell. A downlink grant may at least be used for scheduling the PDSCH in the same slot in which the downlink grant was transmitted. Downlink assignment includes frequency domain resource allocation for PDSCH, time domain resource allocation, MCS (Modulation and Coding Scheme) for PDSCH, NDI (New Data Indicator) for indicating initial transmission or retransmission, HARQ in downlink Downlink control information such as information indicating the process number and Redundancy version indicating the amount of redundancy added to the codeword during error correction coding is included. A codeword is data after error correction coding. The downlink assignment may include a Transmission Power Control (TPC) command for PUCCH and a TPC command for PUSCH. The uplink grant may include an aggregation level (transmission repetition count) that indicates the number of times PUSCH is repeatedly transmitted. Note that the DCI format for each downlink data transmission includes information (fields) necessary for its use among the above information.

One uplink grant is used to notify the terminal device of the scheduling of one PUSCH in one serving cell. The uplink grant includes information on resource block allocation for transmitting PUSCH (resource block allocation and hopping resource allocation), time domain resource allocation, information on MCS of PUSCH (MCS/redundancy version), information on DMRS port, information on PUSCH It includes uplink control information such as information on retransmission, TPC commands for PUSCH, and downlink channel state information (CSI) requests (CSI requests). The uplink grant may include information indicating an uplink HARQ process number, information indicating a redundancy version, a transmission power control (TPC) command for PUCCH, and a TPC command for PUSCH. Note that the DCI format for each uplink data transmission includes information (fields) necessary for its use among the above information.

The OFDM symbol number (position) for transmitting the DMRS symbol is between the first OFDM symbol of the slot and the last OFDM symbol of the PUSCH resource scheduled in the slot when intra frequency hopping is not applied and PUSCH mapping type A is used. given by the signaled duration of For PUSCH mapping type B, where intra frequency hopping is not applied, the OFDM symbol number (position) where a DMRS symbol is transmitted is given by the scheduled PUSCH resource period. If intra frequency hopping is applied, it is given in terms of duration per hop. For PUSCH mapping type A, only if the higher layer parameter indicating the position of the leading DMRS is 2, and the higher layer parameter indicating the number of additional DMRSs is 3 is supported. Also, for PUSCH mapping type A, the 4-symbol period is applicable only when the higher layer parameter indicating the position of the leading DMRS is 2.

A PDCCH is generated by adding a Cyclic Redundancy Check (CRC) to downlink control information. In the PDCCH, the CRC parity bits are scrambled (exclusive OR operation, also called mask) using a predetermined identifier. Parity bits are C-RNTI (Cell-Radio Network Temporary Identifier), CS (Configured Scheduling)-RNTI, Temporary C-RNTI, P (Paging)-RNTI, SI (System Information)-RNTI, or RA (Random Access) - RNTI, SP-CSI (Semi-Persistent Channel State-Information) - RNTI, scrambled with MCS-C-RNTI. C-RNTI and CS-RNTI are identifiers for identifying terminal devices within a cell. Temporary C-RNTI is an identifier for identifying a terminal device that has transmitted a random access preamble during a contention based random access procedure. C-RNTI and Temporary C-RNTI are used to control PDSCH transmission or PUSCH transmission in a single subframe. The CS-RNTI is used to periodically allocate PDSCH or PUSCH resources. Here, the CS-RNTI scrambled PDCCH (DCI format) is used to activate or deactivate CS type 2. On the other hand, in CS type 1, the control information (MCS, radio resource allocation, etc.) included in the PDCCH scrambled by CS-RNTI is included in the upper layer parameters related to CS, and activation (setting) of CS is performed by the upper layer parameters. conduct. P-RNTI is used to transmit paging messages (Paging Channel: PCH). SI-RNTI is used to transmit SIBs. RA-RNTI is used to send a random access response (message 2 in the random access procedure). SP-CSI-RNTI is used for semi-static CSI reporting. MCS-C-RNTI is used in selecting a low spectral efficiency MCS table.

The PDSCH is used to transmit downlink data (downlink transport block, DL-SCH). The PDSCH is used to transmit system information messages (also called System Information Block: SIB). Part or all of the SIB may be included in the RRC message.

The PDSCH is used to transmit RRC signaling. The RRC signaling transmitted from the base station apparatus may be common (cell-specific) for multiple terminal apparatuses within the cell. That is, user equipment common information within that cell is transmitted using cell-specific RRC signaling. The RRC signaling transmitted from the base station apparatus may be a message dedicated to a certain terminal apparatus (also referred to as dedicated signaling). That is, user equipment specific information is sent to a terminal using dedicated messages.

The PDSCH is used to transmit MAC CE. RRC signaling and/or MAC CE are also referred to as higher layer signaling. PMCH is used to transmit multicast data (Multicast Channel: MCH).

In the downlink wireless communication in FIG. 1, a synchronization signal (SS) and a downlink reference signal (DL RS) are used as downlink physical signals. Downlink physical signals are not used to transmit information output from higher layers, but are used by the physical layer.

The synchronization signal is used by the terminal device to synchronize the frequency domain and time domain of the downlink. A downlink reference signal is used by a terminal device to perform channel estimation/channel correction of a downlink physical channel. For example, downlink reference signals are used to demodulate PBCH, PDSCH, and PDCCH. The downlink reference signal can also be used by the terminal device to measure the downlink channel state (CSI measurement).

A downlink physical channel and a downlink physical signal are also collectively referred to as a downlink signal. Also, an uplink physical channel and an uplink physical signal are collectively referred to as an uplink signal. Downlink physical channels and uplink physical channels are also collectively referred to as physical channels. Downlink physical signals and uplink physical signals are also collectively referred to as physical signals.

BCH, UL-SCH and DL-SCH are transport channels. Channels used in the MAC layer are called transport channels. A transport channel unit used in the MAC layer is also called a transport block (TB) or a MAC PDU (Protocol Data Unit). A transport block is a unit of data that the MAC layer delivers to the physical layer. At the physical layer, transport blocks are mapped to codewords, and encoding processing and the like are performed for each codeword.

FIG. 2 is a schematic block diagram of the configuration of the base station apparatus 10 according to this embodiment. The base station apparatus 10 includes an upper layer processing unit (upper layer processing step) 102, a control unit (control step) 104, a transmitting unit (transmitting step) 106, a transmitting antenna 108, a receiving antenna 110, and a receiving unit (receiving step) 112. composed of Transmission section 106 generates a physical downlink channel according to the logical channel input from upper layer processing section 102 . The transmitting unit 106 includes an encoding unit (encoding step) 1060, a modulation unit (modulation step) 1062, a downlink control signal generation unit (downlink control signal generation step) 1064, a downlink reference signal generation unit (downlink reference signal generation step) 1066 , multiplexing section (multiplexing step) 1068 , and radio transmission section (radio transmission step) 1070 . The receiving unit 112 detects (demodulates, decodes, etc.) a physical uplink channel and inputs the content to the upper layer processing unit 102 . The receiving unit 112 includes a radio receiving unit (radio receiving step) 1120, a channel estimating unit (channel estimating step) 1122, a demultiplexing unit (demultiplexing step) 1124, an equalizing unit (equalizing step) 1126, a demodulating unit ( demodulation step) 1128 and a decoding unit (decoding step) 1130 .

The upper layer processing unit 102 includes a medium access control (MAC) layer, a packet data convergence protocol (PDCP) layer, a radio link control (RLC) layer, a radio resource control (Radio Resource Control: Performs processing of higher layers than the physical layer such as the RRC) layer. Upper layer processing section 102 generates information necessary for controlling transmitting section 106 and receiving section 112 and outputs the information to control section 104 . Upper layer processing section 102 outputs downlink data (DL-SCH, etc.), system information (MIB, SIB), etc. to transmitting section 106 . Note that the DMRS configuration information may be notified to the terminal device by system information (MIB or SIB) instead of notification by an upper layer such as RRC.

The upper layer processing unit 102 generates system information (MIB or a part of SIB) to be broadcast or acquires it from a higher node. Upper layer processing section 102 outputs the system information to be broadcast to transmitting section 106 as BCH/DL-SCH. The MIB is placed on the PBCH in transmitting section 106 . The SIB is mapped to the PDSCH in transmitting section 106 . The upper layer processing unit 102 generates system information (SIB) unique to the terminal device, or acquires it from a higher level. The SIB is mapped to the PDSCH in transmitting section 106 .

The upper layer processing unit 102 sets various RNTIs for each terminal device. The RNTI is used for encryption (scrambling) of PDCCH, PDSCH, and the like. Upper layer processing section 102 outputs the RNTI to control section 104 /transmitting section 106 /receiving section 112 .

The upper layer processing unit 102 uses the downlink data (transport block, DL-SCH) allocated to the PDSCH, system information specific to the terminal device (System Information Block: SIB), RRC message, MAC CE, DMRS configuration information as SIB , and MIB, or DMRS configuration information if not notified by DCI, is generated or acquired from a higher node, and output to transmission section 106 . The upper layer processing unit 102 manages various setting information of the terminal device 20 . Note that part of the radio resource control function may be performed in the MAC layer or the physical layer.

The upper layer processing unit 102 receives information about the terminal device, such as the functions supported by the terminal device (UE capabilities), from the terminal device 20 (via the receiving unit 112). The terminal device 20 transmits its own function to the base station device 10 using a higher layer signal (RRC signaling). Information about the terminal device includes information indicating whether the terminal device supports a given function or information indicating that the terminal device has completed installation and testing for the given function. Whether or not a given function is supported includes whether installation and testing for the given function have been completed.

　If the terminal device supports a predetermined function, the terminal device transmits information (parameters) indicating whether or not the predetermined function is supported. If a terminal device does not support a given function, the terminal device may not transmit information (parameters) indicating whether it supports the given function. That is, whether or not the predetermined function is supported is notified by transmitting information (parameters) indicating whether or not the predetermined function is supported. Information (parameter) indicating whether or not a predetermined function is supported may be notified using one bit of 1 or 0.

Upper layer processing section 102 acquires DL-SCH from the decoded uplink data (including CRC) from receiving section 112 . The upper layer processing unit 102 performs error detection on the uplink data transmitted by the terminal device. For example, the error detection is done at the MAC layer.

The control unit 104 controls the transmission unit 106 and the reception unit 112 based on various setting information input from the upper layer processing unit 102/reception unit 112 . Control section 104 generates downlink control information (DCI) based on the setting information input from upper layer processing section 102 /receiving section 112 and outputs it to transmitting section 106 . For example, the control unit 104 considers the DMRS setting information (whether it is the DMRS configuration 1 or the DMRS configuration 2) input from the upper layer processing unit 102/receiving unit 112, DMRS frequency allocation (DMRS configuration 1 In the case of , an even numbered subcarrier or an odd numbered subcarrier, and in the case of DMRS configuration 2, one of the 0th to 2nd sets) is set, and DCI is generated.

The control unit 104 determines the MCS of PUSCH in consideration of the channel quality information (CSI measurement results) measured by the propagation path estimation unit 1122. The control unit 104 determines an MCS index corresponding to the MCS of the PUSCH. Control section 104 includes the determined MCS index in the uplink grant.

The transmission section 106 generates PBCH, PDCCH, PDSCH, downlink reference signals, etc. according to the signal input from the upper layer processing section 102/control section 104 . Encoding section 1060 converts BCH, DL-SCH, etc. input from upper layer processing section 102 into block code, convolutional code, turbo using a predetermined/determined encoding method by upper layer processing section 102. Encoding (including repetition) is performed using code, polar encoding, LDPC code, or the like. Coding section 1060 punctures the coded bits based on the coding rate input from control section 104 . Modulation section 1062 data-modulates the coded bits input from encoding section 1060 using a predetermined modulation scheme (modulation order) input from control section 104 such as BPSK, QPSK, 16QAM, 64QAM, 256QAM. . The modulation order is based on the MCS index selected by controller 104 .

The downlink control signal generation section 1064 adds CRC to the DCI input from the control section 104 . The downlink control signal generator 1064 performs encryption (scrambling) on the CRC using the RNTI. Furthermore, the downlink control signal generating section 1064 performs QPSK modulation on the DCI to which the CRC is added to generate PDCCH. The downlink reference signal generating section 1066 generates a sequence known by the terminal device as a downlink reference signal. The known sequence is obtained according to a predetermined rule based on a physical cell identifier for identifying base station apparatus 10 or the like.

A multiplexing section 1068 multiplexes the modulation symbols of each channel input from the PDCCH/downlink reference signal/modulation section 1062 . That is, multiplexing section 1068 maps PDCCH/downlink reference signals and modulation symbols of each channel to resource elements. Resource elements to be mapped are controlled by downlink scheduling input from the control section 104 . A resource element is the minimum unit of physical resource consisting of one OFDM symbol and one subcarrier. A plurality of resource elements form a resource block (RB), and scheduling is applied using the RB as the minimum unit. When performing MIMO transmission, transmitting section 106 includes coding section 1060 and modulating section 1062 in the number of layers. In this case, upper layer processing section 102 sets MCS for each transport block of each layer.

The radio transmission unit 1070 performs Inverse Fast Fourier Transform (IFFT) on the multiplexed modulation symbols and the like to generate OFDM symbols. A radio transmitter 1070 adds a cyclic prefix (CP) to the OFDM symbol to generate a baseband digital signal. Furthermore, radio transmission section 1070 converts the digital signal into an analog signal, removes unnecessary frequency components by filtering, up-converts to a carrier frequency, amplifies the power, and outputs the signal to transmission antenna 108 for transmission.

Receiving section 112 detects (separates, demodulates, and decodes) a signal received from terminal device 20 via receiving antenna 110 according to an instruction from control section 104, and sends the decoded data to upper layer processing section 102/control section 104. input. The radio receiving unit 1120 down-converts the uplink signal received via the receiving antenna 110 into a baseband signal, removes unnecessary frequency components, and amplifies the signal so that the signal level is appropriately maintained. It controls the level, performs quadrature demodulation based on the in-phase and quadrature components of the received signal, and converts the quadrature-demodulated analog signal to a digital signal. Radio receiving section 1120 removes the portion corresponding to CP from the converted digital signal. Radio receiving section 1120 performs Fast Fourier Transform (FFT) on the CP-removed signal to extract a signal in the frequency domain. The frequency domain signal is output to demultiplexing section 1124 .

Based on the uplink scheduling information (uplink data channel allocation information, etc.) input from the control unit 104, the demultiplexing unit 1124 converts the signal input from the radio receiving unit 1120 into PUSCH, PUCCH, and uplink reference signals. and other signals. The separated uplink reference signals are input to the channel estimation section 1122 . The separated PUSCH and PUCCH are output to equalization section 1126 .

The propagation path estimation unit 1122 estimates the frequency response (or delay profile) using the uplink reference signal. A frequency response result obtained by channel estimation for demodulation is input to equalization section 1126 . The propagation path estimation unit 1122 uses the uplink reference signal to measure uplink channel conditions (measurement of RSRP (Reference Signal Received Power), RSRQ (Reference Signal Received Quality), RSSI (Received Signal Strength Indicator)). conduct. Measurement of uplink channel conditions is used for determination of MCS for PUSCH and the like.

The equalization section 1126 performs processing for compensating the influence of the propagation path from the frequency response input from the propagation path estimation section 1122 . As a compensation method, any existing channel compensation such as a method of multiplying MMSE weights or MRC weights, a method of applying MLD, or the like can be applied. The demodulation section 1128 performs demodulation processing based on the information of the modulation scheme determined in advance/instructed by the control section 104 .

The decoding unit 1130 performs decoding processing on the output signal of the demodulation unit based on the coding rate information instructed by the predetermined coding rate/control unit 104 . Decoding section 1130 inputs the decoded data (such as UL-SCH) to upper layer processing section 102 .

FIG. 3 is a schematic block diagram showing the configuration of the terminal device 20 in this embodiment. The terminal device 20 includes an upper layer processing unit (upper layer processing step) 202, a control unit (control step) 204, a transmitting unit (transmitting step) 206, a transmitting antenna 208, a receiving antenna 210, and a receiving unit (receiving step) 212. consists of

The upper layer processing unit 202 processes the medium access control (MAC) layer, the packet data integration protocol (PDCP) layer, the radio link control (RLC) layer, and the radio resource control (RRC) layer. The upper layer processing unit 202 manages various setting information of its own terminal device. The upper layer processing section 202 notifies the base station apparatus 10 of information (UE Capability) indicating the functions of the terminal device supported by the own terminal apparatus via the transmitting section 206 . The upper layer processing unit 202 notifies the UE Capability by RRC signaling.

The upper layer processing unit 202 acquires the decoded data such as DL-SCH and BCH from the receiving unit 212 . The upper layer processing unit 202 generates HARQ-ACK from the DL-SCH error detection result. The upper layer processing unit 202 generates SR. The upper layer processing unit 202 generates UCI including HARQ-ACK/SR/CSI (including CQI report). Further, when DMRS configuration information is notified by the upper layer, upper layer processing section 202 inputs information on the DMRS configuration to control section 204 . The upper layer processing section 202 inputs the UCI and UL-SCH to the transmitting section 206 . Note that part of the functions of the upper layer processing unit 202 may be included in the control unit 204 .

The control unit 204 interprets the downlink control information (DCI) received via the receiving unit 212. The control unit 204 controls the transmission unit 206 according to the PUSCH scheduling/MCS index/TPC (Transmission Power Control) obtained from the DCI for uplink transmission. The control unit 204 controls the receiving unit 212 according to the PDSCH scheduling/MCS index obtained from the DCI for downlink transmission. Further, the control unit 204 identifies the DMRS frequency allocation according to the information about the DMRS frequency allocation (port number) included in the DCI for downlink transmission and the DMRS configuration information input from the upper layer processing unit 202. .

The transmitting unit 206 includes an encoding unit (encoding step) 2060, a modulation unit (modulation step) 2062, an uplink reference signal generation unit (uplink reference signal generation step) 2064, an uplink control signal generation unit (uplink control signal generation step) 2066 , multiplexing section (multiplexing step) 2068 , and radio transmission section (radio transmission step) 2070 .

Coding section 2060 convolutionally encodes the uplink data (UL-SCH) input from upper layer processing section 202 under the control of control section 204 (according to the coding rate calculated based on the MCS index), and converts it to LDPC. Encoding such as encoding, polar encoding, and turbo encoding is performed.

Modulation section 2062 modulates the coded bits input from coding section 2060 with a modulation method/modulation method predetermined for each channel, such as BPSK, QPSK, 16QAM, 64QAM, and 256QAM, instructed by control section 204. (generate modulation symbols for PUSCH).

Uplink reference signal generating section 2064 arranges a physical cell identifier (referred to as PCI, Cell ID, etc.) for identifying base station apparatus 10 and an uplink reference signal, according to an instruction from control section 204. A sequence determined by a predetermined rule (formula) is generated based on the bandwidth, cyclic shift, parameter values for DMRS sequence generation, and frequency allocation.

Uplink control signal generation section 2066 encodes UCI, performs BPSK/QPSK modulation, and generates modulation symbols for PUCCH according to instructions from control section 204 .

When the upper layer parameter (frequencyHopping) related to Rel-15 frequency hopping is set, mode 1 or mode 2 can be set as its value. Mode 2 is slot-to-slot hopping, which is a mode in which when transmission is performed using a plurality of slots, the frequency is changed for each slot and transmitted. On the other hand, mode 1 is intra-slot hopping, in which when one or more slots are used for transmission, the slot is divided into a first half and a second half, and the first half and the second half are transmitted with different frequencies. As frequency allocation in frequency hopping, radio resource allocation in the frequency domain notified by DCI or RRC is applied to the first hop, and frequency allocation of the second hop is applied to the radio resources used in the first hop. , a radio resource shifted by a value set by a higher-layer parameter (frequencyHoppingOffset) regarding the amount of frequency hopping.

Multiplexing unit 2068, uplink scheduling information from the control unit 204 (transmission interval in CS (Configured Scheduling) for uplink included in the RRC message, frequency domain and time domain resource allocation included in DCI, etc.), according to PUSCH , modulation symbols for PUCCH, and uplink reference signals are multiplexed for each transmit antenna port (DMRS port) (that is, each signal is mapped to a resource element).

Here, CS (configured scheduling, configured grant scheduling) will be explained. There are two types of transmission without dynamic grant. One is a configured grant type 1 given by RRC and stored as configured grant and one is given by PDCCH and stored as configured grant based on L1 signaling indicating configured grant activation or deactivation. Cleared configured grant type 2. Type 1 and type 2 are configured in RRC per serving cell and per BWP. Multiple configurations can be active simultaneously only in different serving cells. For Type 2, activation and deactivation are independent between serving cells. For the same serving cell, MAC entities are configured as either type 1 or type 2. When Type 1 is configured, RRC configures the following parameters.
- cs-RNTI: CS-RNTI for retransmission
periodicity: the periodicity of the configured grant type 1 timeDomainOffset: the offset of the resource for SFN=0 in the time domain timeDomainAllocation: the allocation of the configured grant in the time domain, including the parameter startSymbolAndLength nrofHARQ-Processes: the number of HARQ processes, also type 2 is set, RRC sets the following parameters:
cs-RNTI: CS-RNTI for activation, deactivation and retransmission
• periodicity: the periodicity of the configured grant type 2 • nrofHARQ-Processes: the number of HARQ processes or ConfiguredGrantConfig is used to configure uplink transmission without dynamic grant according to two schemes. The actual uplink grant is configured via RRC for Configured Grant Type 1 and given via PDCCH processed by CS-RNTI for Configured Grant Type 2.

The parameter repK set in the upper layer defines the number of repetitions applied to the transmitted transport block. A parameter repK-RV set in the upper layer indicates a redundancy version pattern to be applied repeatedly. If repK-RV is not set (given), the redundancy version of each actual repeat in the configured grant is set to zero. Otherwise, for the n-th transmission opportunity among all actual iterations (including omitted actual iterations) in the K nominal iterations, the set RV sequence (redundancy version pattern) The transmission associated with the (mod (n−1, 4)+1) th value in . Also, the initial transmission of one transport block is started at the first transmission opportunity of K repetitions when the set RV sequence is {0, 2, 3, 1}. If the configured RV sequence is {0, 3, 0, 3}, start on any transmission opportunity of K repetitions associated with RV=0. If the configured RV sequence is {0, 0, 0, 0}, it will start on any transmission opportunity of K repetitions, except for the last transmission opportunity when K=8. For any RV sequence, the iteration is after K iteration transmissions, or the last transmission opportunity during K iterations in period P, or received an uplink grant to schedule the same transport block in period P. Terminates when either of the times is reached first. In Rel-15, the terminal equipment does not expect to set a time period for K repeated transmissions longer than the time period calculated by the period P. For both Type 1 and Type 2 PUSCH transmissions with configured grants, when the terminal is set with repK>1, the terminal repeats its transport block over repK consecutive slots. At this time, the terminal equipment applies the same symbol allocation in each slot. If the terminal's procedure for slot configuration determination determines that the symbols of the allocated slot are downlink symbols, the transmission in that slot is skipped for multi-slot PUSCH transmission. If repK is set, the value can be 1 time, 2 times, 4 times, or 8 times. However, if the RRC parameter itself does not exist, the number of repetitions is set to 1 for transmission. Also, repK-RV can be set to {0, 2, 3, 1}, {0, 3, 0, 3}, or {0, 0, 0, 0}. Note that signals of different redundancy versions generated from the same transport block are signals composed of the same transport block (information bit sequence), but differ in at least part of the coded bits composed.

In NR Release 16, PUSCH repetition type B was specified. Except for PUSCH, which transmits CSI reports without transport blocks, the nominal number of repetitions is given by the higher layer parameter numberofrepetitions. Let K _s be the slot where PUSCH transmission starts, N _{symb be} the number of symbols per slot, S be the start symbol for the beginning of the slot, and L be the number of consecutive symbols counted from the symbol S assigned as PUSCH. The slot where repetition starts is given by K _s +ceil((S+n·L)/N _symb ), and the start symbol for the beginning of the slot is given by mod(S+n·L, N _symb ). Also, the slot where the nominal repetition ends is K _s + ceil ((S + (n + 1) · L - 1) / N _symb ), the end symbol for the beginning of the slot is mod (S + (n + 1) · L - 1, N _symb ).

For PUSCH repetition type B, after determining invalid symbols due to TDD configuration and reception of downlink control information for each of the K nominal repetitions, the remaining symbols are for PUSCH repetition type B transmission, Considered a potentially valid symbol. If the number of potentially valid symbols for PUSCH repetition type B transmission in a nominal repetition is greater than zero, then that nominal repetition constitutes one or more actual repetitions. Here, each actual repetition constitutes a set of consecutive valid symbols used for PUSCH repetition type B transmission within the slot. The actual repetition by one symbol is omitted except when L=1. Actual iterations are omitted based on other conditions. Redundancy versions are applied based on the actual number of iterations.

Explain frequency hopping between repetitions in PUSCH repetition type B. The start RB in the actual iteration within the nth nominal iteration is determined by the start RB in the uplink BWP when mod(n,2)=0, and when mod(n,2)=1, It is determined by the start RB in the uplink BWP, the offset during frequency hopping notified by RRC signaling, and the bandwidth of the uplink BWP. On the other hand, in inter-slot frequency hopping, a start RB is determined based on a certain slot number.

With PUSCH mapping type B, a DMRS is placed at the beginning of a slot. FIG. 4 shows an example of DMRS arrangement described in Non-Patent Document 2. In FIG. In FIG. 4, D denotes a downlink symbol, G a guard symbol, U an uplink symbol, and DMRS symbols are hatched. As a result, in the current specifications, the allocation of DMRSs is biased across S slots and U slots. This is because the DMRS cannot be shared between the S slot and the U slot, that is, the joint channel estimation cannot be applied, so it is necessary to arrange the DMRS at the beginning of the U slot. However, in the DMRS arrangement of the current specifications, there is a problem that the accuracy of channel estimation differs depending on the data symbol. For example, since the last symbol of the U slot is temporally distant from the DMRS, the channel estimation accuracy is low. , and high channel estimation accuracy can be expected. However, there is a possibility that an error will occur in the entire packet (coding block, transport block) due to the last data symbol of the U slot with low accuracy. Therefore, Non-Patent Document 2 proposes a smart DMRS arrangement as shown in FIG. 4 as a DMRS arrangement suitable for joint channel estimation. In smart DMRS allocation, the DMRS is allocated at the beginning of the allocation, and the DMRS is allocated at approximately equal intervals (constant intervals) within the allocation, so data symbols with lower channel estimation accuracy are generated compared to the current specifications. can be made difficult.

Although Non-Patent Document 2 does not disclose signaling for performing smart DMRS arrangement or specific DMRS arrangement criteria, for example, parameters related to joint channel estimation are set, and joint channel estimation is applied according to the parameters. / It is conceivable to decide non-applicability. When joint channel estimation is applied, the DMRS deployment of the current specifications (up to Release 16) causes a large deviation in channel estimation accuracy. It becomes possible to The range to which joint channel estimation is applied, that is, how many symbols in time over which DMRSs are shared may be set by signaling different from RRC signaling for joint channel estimation. Note that the applicable range may be set as a parameter of RRC signaling related to joint channel estimation.

However, the DMRS arrangement of the current specifications can apply multi-user MIMO in which resources are shared at the same frequency and at the same time among multiple terminal devices having the same slot configuration. Application of multi-user MIMO can improve system throughput (cell throughput). Even when smart DMRS deployment is used, joint channel estimation can be set and multi-user MIMO can be applied between transmitters with the same DMRS configuration. However, joint channel estimation is configured for multiple terminals participating in multi-user MIMO, and the DMRS deployment should also be identical. In other words, since the number of terminal devices that can participate in multi-user MIMO is limited, the possibility of applying multi-user MIMO decreases. As a result, cell throughput is reduced. Although multi-user MIMO is shown as an example here, multi-user MIMO is not limited as long as it is a technology in which a plurality of terminal devices share radio resources. The same can be said for other techniques such as Non-Orthogonal Multiple Access (NOMA). Furthermore, when considering orthogonalizing DMRS with transmission of a terminal (or another base station) in another cell (transmission on any link, such as downlink transmission, uplink transmission, sidelink transmission, etc.) , it is necessary to match settings so that the DMRS allocation is the same as that of terminal equipment in other cells, and coordination between base station equipment is required.

Therefore, it is desirable to be able to apply the DMRS arrangement of the current specifications even when joint channel estimation is applied. In other words, in addition to RRC signaling (parameters, elements, information elements) that configure application of joint channel estimation, there is RRC signaling that specifies DMRS allocation, so that DMRS allocation can be matched with other terminal devices. This makes it easier to apply multi-user MIMO and the like. As a result, cell throughput can be increased. Note that the above two settings do not necessarily need to apply different signaling. For example, the RRC signaling may be signaling related to joint channel estimation, and the parameters of the signaling may be the current specification DMRS arrangement and the smart DMRS arrangement. When the signaling is set by RRC, transmission is performed by a DMRS transmission method (such as keeping the phase constant) for performing joint channel estimation regardless of the value. By this means, application/non-application of joint channel estimation and setting of DMRS allocation when joint channel estimation is applied can be performed without increasing RRC signaling. In addition, although the RRC signaling has been described above as an example, the present invention is not limited to RRC signaling and can also be applied to dynamic signaling by DCI. Furthermore, depending on the scheduling method, it may be changed whether the setting is performed by RRC signaling or by DCI. For example, in the case of configured grant scheduling type 1, which is a scheduling method in which resources for terminal device transmission are allocated only by RRC signaling, application of joint channel estimation is set by RRC signaling, and configured grant scheduling type 2 or dynamic scheduling, in the case of a scheduling method in which resources for terminal device transmission are allocated by DCI, application of joint channel estimation may be set by DCI. However, setting the application of joint channel estimation by DCI above may be only for dynamic scheduling. In this way, by enabling settings for performing joint channel estimation and settings for DMRS allocation, it is possible to match DMRS allocations among a plurality of terminal apparatuses. As a result, there are more opportunities to apply multi-user MIMO, so cell throughput can be increased.

By the way, repeated transmission is an important technique for realizing low delay because data can be decoded for each repeated transmission, and error judgment can be made during repeated transmission. However, considering the entire repeated transmission, there is a possibility that the transmission characteristics can be improved by lowering the coding rate rather than repeating the transmission. Therefore, it is conceivable to transmit one TB (transport block) using a plurality of slots. Non-Patent Document 3 proposes switching between repeated transmission and single TB transmission by dynamic signaling. As a result, repeated transmission can be applied to secure a low delay, and batch encoding transmission of 1 TB can be performed to improve transmission characteristics, making it possible to perform control according to QoS.

If the same DMRS arrangement as for repeated transmission is applied during transmission in 1 TB, channel estimation accuracy will be biased due to biased DMRSs when considering all allocated resources. Therefore, when transmitting 1 TB across multiple slots by dynamic signaling, a different DMRS arrangement from the current DMRS arrangement is applied. As a result, good transmission characteristics can be obtained with a small amount of control information.

The above will be explained with reference to the drawings. An example is shown in FIG. The upper part of FIG. 5 shows an example of repeated transmission. The figure shows an example in which the actual repetition is three times, each consisting of 8 symbols, 2 symbols, and 6 symbols. FIG. 5 is an example of PUSCH mapping type B and the DMRS addition position is set to "pos3". FIG. 6 shows a table showing DMRS positions up to Release 16. From FIG. 6, with PUSCH mapping type B, when the DMRS addition position is "pos3", in the case of 8 symbols, "l ₀ , 3, 6", in the case of 2 symbols, "l ₀ ", in the case of 6 symbols is "l ₀ , 4". In the case of PUSCH mapping type B, since "l ₀ =0" according to the NR specification, DMRS symbols are arranged at the hatched positions in FIG. The lower part of FIG. 5 shows an example in which 1 TB is transmitted using resources allocated by multiple repeated transmissions or multiple slot transmissions instead of repeated transmissions. The figure shows an example in which the specifications up to NR release 16 are followed and the DMRS is determined every 14 symbols at maximum. Since the allocation is 16 symbols, it is divided into 14 symbols and 2 symbols. From FIG. 6, with PUSCH mapping type B, when the DMRS additional position is "pos3", DMRS symbols are arranged at positions (positions) of "l ₀ , 3, 6, 9" with 14 symbols allocated, and with 2 symbols A DMRS symbol is placed at the position of 'l ₀ '. As a result, the DMRS allocation for 1 TB transmission has less DMRS bias (only one data symbol between DMRSs) than the DMRS allocation for repeated transmission in the upper part of FIG. Note that in the example of FIG. 5, the number of DMRS symbols is one less for 1 TB. Another example is shown in FIG. FIG. 7 shows an example of PUSCH mapping type B, in which "pos0" is set as the DMRS additional position. In the example of FIG. 7 as well, the DMRS bias (only one data symbol between DMRSs) is reduced. In this way, when switching between repeated transmission and 1 TB transmission by dynamic signaling, the DMRS arrangement is also changed. This allows DMRS deployment to be switched without additional signaling. Although an example of dynamic signaling is shown above, higher layer signaling such as RRC signaling may be used instead of dynamic signaling. For example, RRC parameters for performing 1 TB transmission may be set, and when the RRC parameters for performing 1 TB transmission are set, DMRS allocation may be smart DMRS allocation. Alternatively, whether to repeat transmission or 1 TB may be set by RRC signaling, and DMRS allocation may be notified by dynamic signaling by DCI. Alternatively, smart DMRS deployment may be applied when RRC parameters (information elements) for smart DMRS deployment are defined and RRC parameters (information elements) for smart DMRS deployment are configured. Furthermore, one of a plurality of parameter sets may be set as the RRC parameter for the smart DMRS deployment, and one value may be designated from the parameter set. The parameter set may specify the number of consecutive slots to apply smart DMRS deployment. By separating signaling in this way, it is possible to dynamically change the arrangement of DMRSs according to the situation of other terminal devices. Although an example in which smart DMRS is applied to radio resources for transmission in one TB is shown, the present invention is not limited to this, and smart DMRS may be applied by dividing the allocated radio resources by slot boundaries. . Note that when smart DMRS is applied, each DMRS symbol is transmitted with the same power and the same phase (within a predetermined range) in the relevant DMRS.

Next, a conventional transport block size determination method will be described. First, the control unit of the terminal device determines the number of resource elements (N _RE ) in the slot as follows when the retransmission is not due to a retransmission request. First, the number of resource elements (REs) in one physical resource block (PRB) allocated for PUSCH (N' _RE ) based on N' _RE = N _SC × N _symb - N _DMRS - N _oh decide. where N _SC is the number of frequency domain subcarriers in one physical resource block, 12, N _symb is the number of symbols in PUSCH allocation, and N _DMRS is for DMRS per PRB indicated by RRC signaling or dynamic signaling. , N _oh is the overhead set by RRC signaling. If Noh is not configured by _RRC signaling, _Noh is assumed to be zero. For PUSCH repetition type B, N _DMRS is determined assuming a nominal repetition of length (duration) of L symbols without segmentation. Next, the terminal determines the total number of REs allocated for PUSCH (N _RE ) by N _RE =min(156, N′ _RE )×n _PRB . Here, n _PRB is the total number of PRBs allocated to the terminal device. Using the obtained N _RE , an intermediate variable N _info without quantization is calculated. N _info is given by N _info =N _RE ×R×Q _m ×ν. Here, R is the target coding rate and _Qm is the modulation order, which are calculated from the MCS index and the MCS table notified by RRC signaling or DCI. ν is the number of transmission layers. If the non-quantized intermediate variable N _info is less than or equal to 3284, determine the quantized intermediate variable N' _info based on N' _info =max(24, 2n×floor(N _info /2 ⁿ )). where n=max(3, floor(log ₂ (N _info ))−6). Using FIG. 11, determine the closest value that does not exceed N' _info as TBS. Description of the case of non-quantized intermediate variables N _info > 3284 is omitted here, but specifications for calculating N' _info based on a formula without using a table such as the one shown in FIG. 11 are adopted in NR. .

Next, a method for determining the transport block size in this embodiment will be described. For repeated transmissions, the conventional TBS determination method is applied to the first iteration. When collective TB transmission is performed by higher layer signaling and/or dynamic signaling from the base station, N _info is changed by changing the N _RE used for TBS calculation. One method is to use a nominal iteration number X for allocation reservation, and determine based on N′ _RE =X×(N _SC ×N _symb −N _DMRS )−N _oh . Note that N′ _RE =X×(N _SC ×N _symb −N _DMRS −N _oh ), and N _oh may also be multiplied by X. Note that X may be the actual number of repetitions instead of the nominal number of repetitions. Another way is to define N' _symb as different from N _symb as N' _RE =N _SC ×N' _symb -N _DMRS -N _oh . For example, when there is signaling for repetition and there is also a setting for collective TB, the number of symbols used for one PUSCH transmission is set to N′ _symb , which is the number of symbols allocated for the entire repetition. For example, in FIG. 5, N _symb is 8, which is the actual number of symbols included in repetition 1, but in the case of lumped TB, N′ _symb =16. Note that this allows N' _symb to be defined as different from N _symb .

N _DMRS should also be configured, but should be determined considering the number of symbols to be allocated across repetitions. N _DMRS =5 in FIG. However, N _DMRS is a value set on the basis of one slot, and the current specifications do not assume the number of symbols exceeding 14 OFDM symbols. Therefore, when there are allocations exceeding 14 symbols, N _DMRSs may be set by separating every 14 symbols. At this time, similarly, _N'symb may be a value of 14 or less, or _N'symb may be calculated independently of the DMRS number N _DMRS . In this case, N _DMRS =4. Note that the reference value is not fixed at 14, and may be set by RRC signaling or the like.

The radio transmission unit 2070 performs IFFT (Inverse Fast Fourier Transform) on the multiplexed signal to generate OFDM symbols. Radio transmission section 2070 adds a CP to the OFDM symbol to generate a baseband digital signal. Further, the radio transmission section 2070 converts the baseband digital signal to an analog signal, removes unnecessary frequency components, converts it to a carrier frequency by up-conversion, amplifies the power, and transmits the signal to the base station via the transmission antenna 208. Send to device 10 .

The receiving unit 212 includes a radio receiving unit (radio receiving step) 2120, a demultiplexing unit (demultiplexing step) 2122, a channel estimating unit (channel estimating step) 2144, an equalizing unit (equalizing step) 2126, a demodulating unit ( demodulation step) 2128 and a decoding unit (decoding step) 2130 .

Radio receiving section 2120 down-converts the downlink signal received via receiving antenna 210 into a baseband signal, removes unnecessary frequency components, and adjusts the amplification level so that the signal level is appropriately maintained. Based on the in-phase and quadrature components of the received signal, it performs quadrature demodulation, and converts the quadrature-demodulated analog signal to a digital signal. Radio receiving section 2120 removes the portion corresponding to the CP from the converted digital signal, performs FFT on the CP-removed signal, and extracts the signal in the frequency domain.

The demultiplexing unit 2122 demultiplexes the extracted frequency-domain signals into downlink reference signals, PDCCH, PDSCH, and PBCH. A channel estimator 2124 estimates a frequency response (or delay profile) using a downlink reference signal (DM-RS, etc.). A frequency response result obtained by channel estimation for demodulation is input to equalization section 1126 . The propagation path estimation unit 2124 uses a downlink reference signal (such as CSI-RS) to measure uplink channel conditions (RSRP (Reference Signal Received Power), RSRQ (Reference Signal Received Quality), RSSI (Received Signal Strength Indicator) and SINR (Signal to Interference plus Noise power Ratio) measurement). Measurement of downlink channel conditions is used for determination of MCS for PUSCH and the like. Measurement results of downlink channel conditions are used for determination of CQI index and the like.

The equalization section 2126 generates equalization weights based on the MMSE criterion from the frequency response input from the channel estimation section 2124 . Equalization section 2126 multiplies the input signal (PUCCH, PDSCH, PBCH, etc.) from demultiplexing section 2122 by the equalization weight. The demodulation section 2128 performs demodulation processing based on information on the modulation order determined in advance/instructed by the control section 204 .

The decoding unit 2130 performs decoding processing on the output signal of the demodulation unit 2128 based on the coding rate information instructed by the predetermined coding rate/control unit 204 . The decoding unit 2130 inputs the decoded data (DL-SCH etc.) to the upper layer processing unit 202 .

(Second embodiment)
In repeated transmission, a reference repetition unit (number of OFDM symbols) L and repetition number K are notified from the base station apparatus to the terminal apparatus by RRC signaling or DCI. However, when considering uplink transmission, the number of symbols of L×K is not necessarily continuously reserved for uplink use. That is, in the case of TDD (Time Division Multiplexing), downlink (DL) and guard symbol allocation are required, and uplink resources cannot be secured continuously, and there is a possibility that part (or all) of the allocation cannot be used. As shown in Figure 8, the specifications up to Release 16 define nominal repetitions, including invalid symbols due to DL assignments, etc., and define actual repetitions in consideration of invalid symbols. . Here, when a value of 2 or more is set as the repetition unit L, when only one symbol can be secured for actual repetition transmission based on nominal repetition as shown in the figure, actual repetition transmission is not performed, Transmission is skipped (omitted). However, this is not the case when L=1. This may be because the repetition of transmitting only DMRS symbols does not make sense if joint channel estimation is not applied. On the other hand, when joint channel estimation is performed, iterations that transmit only DMRS symbols can also be used for data demodulation of previous and subsequent iterations. Therefore, in Non-Patent Document 2, as shown in FIG. 9, even when L=2 or more and only one symbol can actually be secured for repeated transmission, transmission is not omitted, and DMRS is transmitted and used for joint channel estimation. Proposed.

However, when only DMRS is transmitted in repeated transmissions consisting of 1 (single) symbol, in the case of PUSCH mapping type B (repetition type B), the beginning of the next repetition is also DMRS, resulting in excessive DMRS. Therefore, as shown in FIG. 10, data transmission using a single symbol under predetermined conditions will be described below.

For example, if the joint channel estimation is configured in the RRC signaling, and the number of symbols in the actual repetition is 1 with L=2 or more, the 1 symbol is a data symbol instead of a DMRS, resulting in excess DMRS. can be avoided and transmission characteristics can be improved. Note that one OFDM symbol may be composed of OFDM symbols including both DMRS and data. Although the case of PUSCH mapping type B (and repetition type B) has been described above, it may be applied to the case of PUSCH mapping type A as well. In the case of PUSCH mapping type A, since the head symbol of transmission is not always DMRS, when the number of symbols in actual repetition is 1, data symbols are transmitted. Although FIG. 10 shows an example of repetition, RRC signaling and/or dynamic signaling may be used to transmit one transport block on one PUSCH instead of actual repetition.

As described above, the redundancy version is changed for each repetition, but when DMRS is transmitted in repeated transmission of one (single) symbol, it is not regarded as an actual repetition, and a redundancy indicating a puncture pattern in an encoded bit sequence is used. It may not be counted because it is a Darcy version change. However, when an OFDM symbol including both DMRS and data signals is transmitted, it may be counted for changing the redundancy version. Also, in repeated transmission consisting of 1 (single) symbol, if the repetition is the last transmission, or if the next OFDM symbol is transmitted on a different frequency (subcarrier) by frequency hopping, DMRS transmission Instead, either no transmission, data transmission, or OFDM transmission consisting of DMRS and data may be performed. In addition, even if the frequency offset related to frequency hopping is set to 0 and transmission is actually performed on the same frequency, if frequency hopping is set by RRC signaling or the like, no transmission, data transmission, Alternatively, either OFDM transmission consisting of DMRS and data may be performed.

The program that runs on the device related to the present invention may be a program that controls the Central Processing Unit (CPU) and the like to make the computer function so as to realize the functions of the above-described embodiments related to the present invention. The program or information handled by the program is temporarily read into volatile memory such as Random Access Memory (RAM) during processing, or stored in non-volatile memory such as flash memory or Hard Disk Drive (HDD), The CPU reads, modifies, and writes accordingly.

It should be noted that part of the devices in the above-described embodiments may be realized by a computer. In that case, the program for realizing the functions of the embodiment may be recorded in a computer-readable recording medium. It may be realized by causing a computer system to read and execute the program recorded on this recording medium. The "computer system" here is a computer system built in the device, and includes hardware such as an operating system and peripheral devices. The "computer-readable recording medium" may be any of semiconductor recording media, optical recording media, magnetic recording media, and the like.

Furthermore, "computer-readable recording medium" means a medium that dynamically stores programs for a short period of time, such as a communication line for transmitting a program via a network such as the Internet or a communication line such as a telephone line. , such as a volatile memory inside a computer system that serves as a server or a client in that case, may also include something that holds the program for a certain period of time. Further, the program may be for realizing part of the functions described above, or may be capable of realizing the functions described above in combination with a program already recorded in the computer system.

Also, each functional block or feature of the apparatus used in the embodiments described above may be implemented or performed in an electrical circuit, typically an integrated circuit or multiple integrated circuits. An electrical circuit designed to perform the functions described herein may be a general purpose processor, digital signal processor (DSP), application specific integrated circuit (ASIC), field programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic, discrete hardware components, or combinations thereof. A general-purpose processor may be a microprocessor, or any conventional processor, controller, microcontroller, or state machine. The electric circuit described above may be composed of a digital circuit, or may be composed of an analog circuit. In addition, when an integrated circuit technology that replaces current integrated circuits emerges due to advances in semiconductor technology, it is also possible to use integrated circuits based on this technology.

It should be noted that the present invention is not limited to the above-described embodiments. In the embodiments, an example of the device was described, but the present invention is not limited to this, and stationary or non-movable electronic equipment installed indoors and outdoors, such as AV equipment, kitchen equipment, It can be applied to terminal devices or communication devices such as cleaning/washing equipment, air conditioning equipment, office equipment, vending machines, and other household equipment.

Although the embodiment of this invention has been described in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes etc. within the scope of the gist of this invention are also included. In addition, the present invention can be modified in various ways within the scope of the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments are also included in the technical scope of the present invention. be Moreover, it is an element described in each said embodiment, and the structure which replaced the element with which the same effect is produced is also included.

INDUSTRIAL APPLICABILITY The present invention is suitable for use in base station apparatuses, terminal apparatuses, and communication methods.

Claims (6)

1. A terminal device that transmits to a base station device,
   an upper layer processing unit that receives higher layer signaling including two parameters of a repetition unit and a repetition number from the base station apparatus;
   Using the higher layer signaling and a predetermined field included in downlink control information, the first transmission that performs repeated transmission using the two parameters, and the radio resources allocated by the two parameters a control unit that switches a second transmission that transmits one transport block;
   A multiplexing unit that switches between the DMRS allocation related to the first transmission and the DMRS allocation related to the second transmission according to a predetermined field included in the downlink control information;
   and a terminal device.
2. The multiplexing unit configures at least one reference signal for each repetition during DMRS configuration associated with the first transmission, and the two parameters during DMRS configuration associated with the second transmission. 2. The terminal device according to claim 1, which arranges at least one reference signal in a radio resource allocated by .
3. When performing DMRS allocation related to the second transmission, the multiplexing unit divides the radio resources allocated by the two parameters into 14 symbols, and arranges DMRSs at predetermined positions of the divided symbols. The terminal device according to claim 1, wherein
4. A base station device that receives a signal transmitted by a terminal device,
   a higher layer processing unit that generates higher layer signaling including two parameters of a repetition unit and a repetition number for the terminal device;
   Using a predetermined field included in the downlink control information, a first transmission that performs repeated transmission using the two parameters, and one transport block using the radio resources allocated by the two parameters a downlink control signal unit for notifying switching of the second transmission to be transmitted and switching between the DMRS allocation related to the first transmission and the DMRS allocation related to the second transmission;
   and a base station device.
5. The downlink control signal unit arranges at least one reference signal for each repetition during DMRS allocation related to the first transmission, and arranges at least one reference signal during DMRS allocation related to the second transmission. 5. The base station apparatus according to claim 4, which notifies that at least one reference signal is allocated to radio resources allocated by two parameters.
6. When performing the DMRS arrangement related to the second transmission, the downlink control signal unit divides the radio resources allocated by the two parameters into 14 symbols, and places the divided symbols at predetermined positions. 5. The base station apparatus according to claim 4, wherein DMRS is arranged.

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