JP7704757B2 - Terminal device and base station device - Google Patents

Description

The present invention relates to a terminal device, a base station device, and a communication method thereof.
This application claims priority to Japanese Patent Application No. 2020-134327, filed in Japan on August 7, 2020, the contents of which are incorporated herein by reference.

In the NR (New Radio) communication system specified by the 3GPP (Third Generation Partnership Project), an OFDM symbol containing one or more DMRS (Demodulation Reference Signals) is inserted into a slot consisting of multiple OFDM symbols. The 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 repeat transmission to improve communication reliability and expand coverage. With inter-slot repeat, the same data can be repeatedly transmitted in multiple slots. However, since multiple slots are required for repeated transmission, there was a problem in terms of latency. Therefore, in NR Release 16, intra-slot repeat transmission was specified. With intra-slot repeat transmission, multiple repetition units can be set within a slot and transmission can be performed.

In specifications up to Rel-16, the DMRS that could be used for channel estimation was limited to within a repetition unit or within a slot, but the accuracy of channel estimation can be significantly improved by using DMRS contained in different repetition units or different slots. Therefore, in NR Release 17, DMRS sharing (DMRS bundling), which makes it possible to use DMRS contained in different repetition units or different slots, is being considered. (Non-Patent Document 1)

DMRS sharing (DMRS bundling) is effective not only when moving at low speeds but also when moving at high speeds.

Qualcomm, “Potential techniques for coverage enhancements,” 3GPP TSG-RAN WG1 Meeting #101, R1-2004499, May 2020.

DMRS sharing has been proposed in 3GPP, but no consideration has been given to how to actually introduce it into the system. In addition, other technologies besides DMRS sharing can be considered as methods for expanding coverage.

One aspect of the present invention has been made in consideration of these circumstances, and its purpose is to expand coverage by changing the DMRS policy method and control information related to DMRS.

In order to solve the above-mentioned problems, the configurations of a base station device, a terminal device, and a communication method according to one embodiment of the present invention are as follows.

(1) One aspect of the present invention is a terminal device that communicates with a base station device through repeated transmission, and includes an upper layer processing unit that sets a repetition number and a redundancy version in the repeated transmission, and a slot configuration unit that configures slots, and the slot configuration unit changes the number of reference signals in each repeated transmission based on the redundancy version in the repeated transmission.
(2) In one aspect of the present invention, in a repeated transmission in which a value other than 0 is set as the redundancy version, the slot configuration section includes a smaller number of reference signals than in a repeated transmission in which the redundancy version is set to 0.
(3) In one aspect of the present invention, the slot configuration unit transmits a reference signal only in repeated transmissions in which 0 is set as the redundancy version.
(4) One aspect of the present invention is a base station device that communicates with a terminal device through repeated transmission, and includes an upper layer processing unit that sets a repetition number and a redundancy version in the repeated transmission, and a slot configuration unit that configures slots, and the slot configuration unit changes the number of reference signals in each repeated transmission based on the redundancy version in the repeated transmission.
(5) In one aspect of the present invention, in a repeated transmission in which a value other than 0 is set as the redundancy version, the slot configuration section includes a smaller number of reference signals than in a repeated transmission in which the redundancy version is set to 0.
(6) In one aspect of the present invention, the slot configuration unit transmits a reference signal only in a repeated transmission in which 0 is set as the redundancy version.

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

1 is a diagram illustrating an example of the configuration of a communication system 1 according to an embodiment of the present invention. FIG. 2 is a diagram illustrating an example of the configuration of a base station device according to the present embodiment. FIG. 2 is a diagram illustrating an example of the configuration of a terminal device according to the present embodiment. FIG. 1 is a diagram illustrating an example of DMRS sharing according to the present embodiment. FIG. 13 is a diagram showing an example of DMRS sharing during frequency hopping according to the present embodiment. A figure showing an example of DMRS placement using RV patterns in this embodiment.

The communication system according to this embodiment includes a base station device (cell, small cell, serving cell, component carrier, eNodeB, Home eNodeB, gNodeB) and a terminal device (terminal, mobile terminal, UE: User Equipment). In the communication system, in the case of downlink, the base station device is a transmitting device (transmitting point, transmitting antenna group, transmitting antenna port group, TRP (Tx/Rx Point)), and the terminal device is a receiving device (receiving point, receiving terminal, receiving antenna group, receiving antenna port group). In the case of uplink, the base station device is a receiving device, and the terminal device is a transmitting device. 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 that requires human intervention. In other words, it can also be applied to data communication forms that do not require 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). In this case, the terminal device becomes an MTC terminal. The communication system can use a multicarrier transmission method such as CP-OFDM (Cyclic Prefix - Orthogonal Frequency Division Multiplexing) in the uplink and downlink. When upper layer parameters related to the Transform precoder are set in the uplink, the communication system uses a transmission method such as DFTS-OFDM (Discrete Fourier Transform Spread - Orthogonal Frequency Division Multiplexing, also referred to as SC-FDMA) that applies Transform precoding, that is, DFT. In the following, a case will be described in which the OFDM transmission method is used in the uplink and downlink, but the present invention is not limited to this and other transmission methods can also be applied.

The base station device and terminal device in this embodiment can communicate in frequency bands known as licensed bands, for which permission to use (license) has been obtained from the country or region in which the wireless carrier provides services, and/or in frequency bands known as unlicensed bands, for which permission to use (license) is not required from the 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)
1 is a diagram showing an example of the configuration of a communication system 1 according to the present embodiment. The communication system 1 in the present embodiment includes a base station device 10 and a terminal device 20. A coverage 10a is a range (communication area) in which the base station device 10 can connect (communicate) with the terminal device 20 (also called a cell). The base station device 10 can accommodate multiple terminal devices 20 in the coverage 10a.

1, the uplink wireless communication r30 includes at least the following uplink physical channels: The 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). Uplink control information includes positive acknowledgement (ACK)/negative acknowledgement (NACK) for downlink data. Here, downlink data refers to Downlink transport block, Medium Access Control Protocol Data Unit (MAC PDU), Downlink-Shared Channel (DL-SCH), Physical Downlink Shared Channel (PDSCH), etc. ACK/NACK is also called HARQ-ACK (Hybrid Automatic Repeat request ACKnowledgement), HARQ feedback, HARQ response, or HARQ control information, a signal indicating delivery confirmation.

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 one or two OFDM symbols, and other PUCCHs are composed of four to fourteen OFDM symbols. PUCCH format 0 and PUCCH format 1 are composed of a bandwidth of 12 subcarriers. In PUCCH format 0, 1 bit (or 2 bits) of ACK/NACK is transmitted in a resource element of 12 subcarriers and one OFDM symbol (or two OFDM symbols).

The uplink control information includes a Scheduling Request (SR) that is used to request Uplink-Shared Channel (UL-SCH) resources for the initial transmission. The Scheduling Request indicates a request for UL-SCH resources for the initial transmission.

The uplink control information includes downlink channel state information (CSI). The downlink channel state information includes a rank indicator (RI) indicating a suitable spatial multiplexing number (number of layers), a precoding matrix indicator (PMI) indicating a suitable precoder, a channel quality indicator (CQI) specifying a suitable transmission rate, and the like. The PMI indicates a codebook determined by the terminal device. The codebook is related to the precoding of the physical downlink shared channel.

In NR, the upper layer parameter RI restriction can be configured. There are multiple configuration parameters for RI restriction, one of which is type 1 single panel RI restriction, which is composed of 8 bits. The type 1 single panel RI restriction, which is a bitmap parameter, forms a bit sequence _r7 , ... _r2 , _r1 , where _r7 , is the most significant bit (MSB) and _r0 , is the least significant bit (LSB). When _{r i} is zero (i is 0, 1, ... 7), PMI and RI reporting corresponding to the precoder associated with the i+1 layer are not allowed. In addition to the type 1 single panel RI restriction, the RI restriction also includes type 1 multi-panel RI restriction, which is composed of 4 bits. The type 1 multi-panel RI restriction, which is a bitmap parameter, forms a bit sequence _r4 , _r3 , _r2 , _r1 , where _r4 , is the most significant bit (MSB) and _r0 , is the least significant bit (LSB). When r _i is zero (i is 0, 1, 2, 3), PMI and RI reporting corresponding to the precoder associated with the i+1 layer is not allowed.

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

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

The PUSCH is used to transmit Radio Resource Control (RRC) signaling. RRC signaling is also referred to as an RRC message, RRC layer information, RRC layer signal, RRC layer parameter, or RRC information element. RRC signaling is information/signal processed in the radio resource control layer. The RRC signaling transmitted from the base station device may be common signaling for multiple terminal devices in a cell. The RRC signaling transmitted from the base station device may be dedicated signaling for a certain terminal device. That is, user device-specific information is transmitted using dedicated signaling for a certain terminal device. The RRC message may include the UE Capability of the terminal device. The UE Capability is information indicating the functions supported by the terminal device.

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

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

In uplink wireless communication, an 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 reference signal (PTRS), etc. The DMRS is related to the transmission of the physical uplink shared channel/physical uplink control channel. For example, when demodulating the physical uplink shared channel/physical uplink control channel, the base station device 10 uses the demodulation reference signal to perform propagation path estimation/propagation path correction.

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

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

In Fig. 1, at least the following downlink physical channels are used in the wireless communication of the downlink r31: The 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 (MIB, Broadcast Channel: BCH) commonly used by terminal devices. The MIB is one of the system information. For example, the MIB includes a downlink transmission bandwidth setting and a system frame number (SFN). The MIB may include information indicating at least a portion 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 the downlink control information, multiple formats (also called DCI formats) based on the application are defined. The DCI format may be defined based on the type and number of bits of the DCI that constitutes one DCI format. Each format is used according to the application. The downlink control information includes control information for downlink data transmission and control information for uplink data transmission. The DCI format for downlink data transmission is also called downlink assignment (or downlink grant). The DCI format for uplink data transmission is also called uplink grant (or uplink assignment).

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

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

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

The PDCCH is generated by adding a Cyclic Redundancy Check (CRC) to the downlink control information. In the PDCCH, the CRC parity bits are scrambled (exclusive-OR operation, also called masking) using a predetermined identifier. The parity bits are scrambled with the Cell-Radio Network Temporary Identifier (C-RNTI), Configured Scheduling (CS)-RNTI, Temporary C-RNTI, Paging (P)-RNTI, System Information (SI)-RNTI, Random Access (RA)-RNTI, Semi-Persistent Channel State-Information (SP-CSI)-RNTI, or MCS-C-RNTI. The C-RNTI and CS-RNTI are identifiers for identifying terminal devices within a cell. The 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. The C-RNTI and the Temporary C-RNTI are used to control PDSCH transmission or PUSCH transmission in a single subframe. The CS-RNTI is used to periodically allocate resources for the PDSCH or PUSCH. Here, the PDCCH (DCI format) scrambled with the CS-RNTI 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 with the CS-RNTI is included in the higher layer parameters related to CS, and the CS is activated (set) by the higher layer parameters. The P-RNTI is used to transmit a paging message (Paging Channel: PCH). The SI-RNTI is used to transmit SIBs. The RA-RNTI is used to transmit the random access response (message 2 in the random access procedure). The SP-CSI-RNTI is used for semi-static CSI reporting. The MCS-C-RNTI is used to select the MCS table with low spectral efficiency.

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 Blocks: SIBs). Some or all of the SIBs can be included in an RRC message.

The PDSCH is used to transmit RRC signaling. The RRC signaling transmitted from the base station device may be common (cell-specific) to multiple terminal devices in a cell. That is, information common to user devices in the cell is transmitted using cell-specific RRC signaling. The RRC signaling transmitted from the base station device may be a message dedicated to a certain terminal device (also referred to as dedicated signaling). That is, information specific to a certain terminal device is transmitted using a message dedicated to a certain terminal device.

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

In the downlink wireless communication in Figure 1, a synchronization signal (SS) and a downlink reference signal (DL RS) are used as downlink physical signals. The 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. The downlink reference signal is used by the terminal device to perform propagation path estimation/propagation path correction of the downlink physical channel. For example, the downlink reference signal is used to demodulate the PBCH, PDSCH, and PDCCH. The downlink reference signal can also be used by the terminal device to measure the downlink channel condition (CSI measurement).

The downlink physical channel and the downlink physical signal are collectively referred to as the downlink signal. The uplink physical channel and the uplink physical signal are collectively referred to as the uplink signal. The downlink physical channel and the uplink physical channel are collectively referred to as the physical channel. The downlink physical signal and the uplink physical signal are collectively referred to as the physical signal.

BCH, UL-SCH and DL-SCH are transport channels. A channel used in the MAC layer is called a transport channel. The unit of the transport channel 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. In the physical layer, the transport block is mapped to a code word, and encoding processing is performed for each code word.

Figure 2 is a schematic block diagram of the configuration of the base station device 10 according to this embodiment. The base station device 10 is configured to include an upper layer processing unit (upper layer processing step) 102, a control unit (control step) 104, a transmission unit (transmission step) 106, a transmission antenna 108, a reception antenna 110, and a reception unit (reception step) 112. The transmission unit 106 generates a physical downlink channel according to the logical channel input from the upper layer processing unit 102. The transmission unit 106 is configured to include 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, a multiplexing unit (multiplexing step) 1068, and a radio transmission unit (radio transmission step) 1070. The reception unit 112 detects the physical uplink channel (demodulation, decoding, etc.) and inputs the contents to the upper layer processing unit 102. The receiving unit 112 is composed of a wireless receiving unit (wireless receiving step) 1120, a propagation path estimating unit (propagation path estimating step) 1122, a demultiplexing unit (demultiplexing step) 1124, an equalization unit (equalization step) 1126, a demodulation unit (demodulation step) 1128, and a decoding unit (decoding step) 1130.

The upper layer processing unit 102 performs processing of layers higher than the physical layer, such as the Medium Access Control (MAC) layer, the Packet Data Convergence Protocol (PDCP) layer, the Radio Link Control (RLC) layer, and the Radio Resource Control (RRC) layer. The upper layer processing unit 102 generates information necessary for controlling the transmitting unit 106 and the receiving unit 112, and outputs it to the control unit 104. The upper layer processing unit 102 outputs downlink data (such as DL-SCH), system information (MIB, SIB), and the like to the transmitting unit 106. Note that the DMRS configuration information may be notified to the terminal device by system information (MIB or SIB) rather than by a higher layer such as RRC.

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

The upper layer processing unit 102 sets various RNTIs for each terminal device. The RNTIs are used for encryption (scrambling) of the PDCCH, PDSCH, etc. The upper layer processing unit 102 outputs the RNTIs to the control unit 104, the transmission unit 106, and the reception unit 112.

The upper layer processing unit 102 generates or acquires from an upper node downlink data (transport block, DL-SCH) arranged in the PDSCH, terminal device-specific system information (System Information Block: SIB), RRC message, MAC CE, DMRS configuration information, system information such as SIB or MIB, or DMRS configuration information if not notified by DCI, and outputs it to the transmission unit 106. The upper layer processing unit 102 manages various setting information of the terminal device 20. Note that some of the functions of radio resource control may be performed in the MAC layer or physical layer.

The upper layer processing unit 102 receives information about the terminal device from the terminal device 20 (via the receiving unit 112), such as functions supported by the terminal device (UE capability). The terminal device 20 transmits its own functions to the base station device 10 by means of upper layer signals (RRC signaling). The information about the terminal device includes information indicating whether the terminal device supports a specified function, or information indicating that the terminal device has completed installation and testing of the specified function. Whether a specified function is supported includes whether installation and testing of the specified function has been completed.

If a terminal device supports a specified function, the terminal device transmits information (parameters) indicating whether or not the specified function is supported. If a terminal device does not support a specified function, the terminal device may not transmit information (parameters) indicating whether or not the specified function is supported. In other words, whether or not the specified function is supported is notified by whether or not information (parameters) indicating whether or not the specified function is supported is transmitted. Note that the information (parameters) indicating whether or not the specified function is supported may be notified using one bit of 1 or 0.

The upper layer processing unit 102 obtains the DL-SCH from the decoded uplink data (including the CRC) from the receiving unit 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 performed 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. The control unit 104 generates downlink control information (DCI) based on the setting information input from the upper layer processing unit 102/reception unit 112 and outputs it to the transmission unit 106. For example, the control unit 104 sets the frequency arrangement of the DMRS (even subcarriers or odd subcarriers in the case of DMRS configuration 1, or one of the 0th to 2nd sets in the case of DMRS configuration 2) in consideration of the setting information regarding the DMRS input from the upper layer processing unit 102/reception unit 112 (whether it is DMRS configuration 1 or DMRS configuration 2), and generates DCI.

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

The transmission unit 106 generates PBCH, PDCCH, PDSCH, downlink reference signal, etc. according to the signal input from the upper layer processing unit 102/control unit 104. The coding unit 1060 performs coding (including repetition) of the BCH, DL-SCH, etc. input from the upper layer processing unit 102 using a coding method determined in advance/by the upper layer processing unit 102, using block code, convolutional code, turbo code, polar coding, LDPC code, etc. The coding unit 1060 punctures the coding bits based on the coding rate input from the control unit 104. The modulation unit 1062 data-modulates the coding bits input from the coding unit 1060 using a modulation method (modulation order) determined in advance/by the control unit 104, such as BPSK, QPSK, 16QAM, 64QAM, 256QAM, etc. The modulation order is based on the MCS index selected by the control unit 104.

The downlink control signal generating unit 1064 adds a CRC to the DCI input from the control unit 104. The downlink control signal generating unit 1064 encrypts (scrambles) the CRC using the RNTI. Furthermore, the downlink control signal generating unit 1064 performs QPSK modulation on the DCI to which the CRC has been added, to generate a PDCCH. The downlink reference signal generating unit 1066 generates a sequence known to the terminal device as a downlink reference signal. The known sequence is determined according to a predetermined rule based on a physical cell identifier for identifying the base station device 10, etc.

The multiplexing unit 1068 multiplexes the modulation symbols of each channel input from the PDCCH/downlink reference signal/modulation unit 1062. That is, the multiplexing unit 1068 maps the modulation symbols of each channel of the PDCCH/downlink reference signal to resource elements. The resource elements to be mapped are controlled by the downlink scheduling input from the control unit 104. A resource element is the smallest unit of physical resources consisting of one OFDM symbol and one subcarrier. A resource block (RB) is composed of multiple resource elements, and scheduling is applied with the RB as the smallest unit. When MIMO transmission is performed, the transmission unit 106 has an encoding unit 1060 and a modulation unit 1062 for the number of layers. In this case, the upper layer processing unit 102 sets the MCS for each transport block of each layer.

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

The receiving unit 112 detects (separates, demodulates, decodes) the received signal from the terminal device 20 via the receiving antenna 110 according to the instruction of the control unit 104, and inputs the decoded data to the upper layer processing unit 102/control unit 104. The wireless receiving unit 1120 converts the uplink signal received via the receiving antenna 110 into a baseband signal by down-conversion, removes unnecessary frequency components, controls the amplification level so that the signal level is appropriately maintained, performs quadrature demodulation based on the in-phase component and quadrature component of the received signal, and converts the quadrature demodulated analog signal into a digital signal. The wireless receiving unit 1120 removes the part corresponding to the CP from the converted digital signal. The wireless receiving unit 1120 performs a fast Fourier transform (FFT) on the signal from which the CP has been removed, and extracts the frequency domain signal. The frequency domain signal is output to the multiplexing and demultiplexing unit 1124.

The multiplexing/demultiplexing unit 1124 separates the signal input from the radio receiving unit 1120 into signals such as PUSCH, PUCCH, and uplink reference signal based on uplink scheduling information (such as uplink data channel allocation information) input from the control unit 104. The separated uplink reference signal is input to the propagation path estimation unit 1122. The separated PUSCH and PUCCH are output to the equalization unit 1126.

The propagation path estimation unit 1122 estimates the frequency response (or delay profile) using the uplink reference signal. The frequency response result estimated for demodulation is input to the equalization unit 1126. The propagation path estimation unit 1122 measures the uplink channel conditions (measures RSRP (Reference Signal Received Power), RSRQ (Reference Signal Received Quality), and RSSI (Received Signal Strength Indicator)) using the uplink reference signal. The measurement of the uplink channel conditions is used to determine the MCS for the PUSCH, etc.

The equalization unit 1126 performs a process of compensating for the influence of the propagation path using the frequency response input from the propagation path estimation unit 1122. As a compensation method, any existing propagation path compensation can be applied, such as a method of multiplying MMSE weights or MRC weights, or a method of applying MLD. The demodulation unit 1128 performs a demodulation process based on information on the modulation method that is predetermined/instructed by the control unit 104.

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

Figure 3 is a schematic block diagram showing the configuration of the terminal device 20 in this embodiment. The terminal device 20 is configured to include 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.

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

The upper layer processing unit 202 obtains decoded data such as DL-SCH and BCH from the receiving unit 212. The upper layer processing unit 202 generates an HARQ-ACK from the error detection result of the DL-SCH. The upper layer processing unit 202 generates an SR. The upper layer processing unit 202 generates UCI including HARQ-ACK/SR/CSI (including a CQI report). In addition, when DMRS configuration information has been notified by the upper layer, the upper layer processing unit 202 inputs information regarding the DMRS configuration to the control unit 204. The upper layer processing unit 202 inputs the UCI and UL-SCH to the transmitting unit 206. Note that some 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 transmitting unit 206 according to the scheduling/MCS index/TPC (Transmission Power Control) of the PUSCH acquired from the DCI for uplink transmission. The control unit 204 controls the receiving unit 212 according to the scheduling/MCS index of the PDSCH acquired from the DCI for downlink transmission. Furthermore, the control unit 204 specifies the frequency arrangement of the DMRS according to information regarding the frequency arrangement (port number) of the DMRS included in the DCI for downlink transmission and the DMRS configuration information input from the upper layer processing unit 202.

The transmitting unit 206 is composed of an encoding unit (encoding step) 2060, a modulation unit (modulation step) 2062, an uplink reference signal generating unit (uplink reference signal generating step) 2064, an uplink control signal generating unit (uplink control signal generating step) 2066, a multiplexing unit (multiplexing step) 2068, and a radio transmitting unit (radio transmitting step) 2070.

The encoding unit 2060 performs convolutional encoding, LDPC encoding, polar encoding, turbo encoding, etc. on the uplink data (UL-SCH) input from the upper layer processing unit 202 according to the control of the control unit 204 (according to the encoding rate calculated based on the MCS index).

The modulation unit 2062 modulates the coded bits input from the coding unit 2060 using a modulation method predetermined for each modulation method/channel instructed by the control unit 204, such as BPSK, QPSK, 16QAM, 64QAM, 256QAM, etc. (to generate modulation symbols for the PUSH).

The uplink reference signal generating unit 2064, in accordance with instructions from the control unit 204, generates a sequence determined by a predetermined rule (formula) based on a physical cell identifier (PCI, also referred to as Cell ID, etc.) for identifying the base station device 10, the bandwidth in which the uplink reference signal is allocated, the cyclic shift, parameter values for generating the DMRS sequence, and frequency allocation, etc.

The uplink control signal generating unit 2066 encodes the UCI, performs BPSK/QPSK modulation, and generates modulation symbols for the PUCCH in accordance with the instructions of the control unit 204.

When the higher layer parameter (frequencyHopping) for frequency hopping of Rel-15 is set, the value can be set to mode 1 or mode 2. Mode 2 is inter-slot hopping, and when multiple slots are used for transmission, the frequency is changed for each slot. On the other hand, mode 1 is intra-slot hopping, and when one or multiple slots are used for transmission, the slot is divided into a first half and a second half, and the frequency is changed between the first half and the second half. For frequency allocation in frequency hopping, the frequency domain radio resource allocation notified by DCI or RRC is applied to the first hop, and the frequency allocation for the second hop is assigned to radio resources shifted by the value set in the higher layer parameter (frequencyHoppingOffset) for the amount of frequency hopping from the radio resources used in the first hop.

The multiplexing unit 2068 multiplexes the modulation symbols for the PUSH, the modulation symbols for the PUCCH, and the uplink reference signal for each transmitting antenna port (DMRS port) in accordance with the uplink scheduling information from the control unit 204 (such as the transmission interval in CS (Configured Scheduling) for the uplink included in the RRC message, the frequency domain and time domain resource allocation included in the DCI, etc.) (i.e., each signal is mapped to a resource element).

Here, we will explain about CS (configured scheduling). There are two types of transmission without dynamic grant. One is configured grant type 1, which is given by RRC and saved as configured grant, and one is configured grant type 2, which is given by PDCCH and saved and cleared as configured grant based on L1 signaling indicating configured grant activation or deactivation. Type 1 and type 2 are configured by 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, the MAC entity is configured with either type 1 or type 2. When type 1 is configured, RRC configures the following parameters:
cs-RNTI: CS-RNTI for retransmission
periodicity: periodicity of configured grant type 1 timeDomainOffset: resource offset with respect to SFN=0 in the time domain timeDomainAllocation: allocation of configured grant in the time domain, including parameter startSymbolAndLength nrofHARQ-Processes: number of HARQ processes. Furthermore, when type 2 is configured, RRC configures the following parameters:
cs-RNTI: CS-RNTI for activation, deactivation, and retransmission
periodicity: periodicity of configured grant type 2 nrofHARQ-Processes: number of HARQ processes, i.e. 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 with CS-RNTI for Configured Grant type 2.

The parameter repK configured by the higher layer defines the number of repetitions applied to the transmitted transport block. repK-RV indicates the redundancy version pattern applied to the repetition. For the nth transmission opportunity in the K repetitions, a transmission associated with the (mod(n-1, 4)+1)th value in the configured RV sequence (redundancy version pattern) is performed. The first transmission of one transport block starts at the first transmission opportunity of the K repetitions if the configured RV sequence is {0, 2, 3, 1}. If the configured RV sequence is {0, 3, 0, 3}, it starts at any transmission opportunity of the K repetitions associated with RV=0. If the configured RV sequence is {0, 0, 0, 0}, it starts at any transmission opportunity of the K repetitions except the last transmission opportunity when K=8. For any RV sequence, the repetition is terminated after K repetitions, or at the last transmission opportunity of the K repetitions in period P, or when an uplink grant for scheduling the same transport block is received within period P, whichever comes first. In Rel-15, the terminal device is not expected to set a time period for K-times repetition transmission longer than the time period calculated by the period P. For both type 1 and type 2 PUSCH transmission by configured grant, when the terminal device sets repK>1, the terminal device repeats the transport block over repK consecutive slots. In this case, the terminal device applies the same symbol arrangement in each slot. If the terminal device procedure for determining the slot arrangement determines (determines) the symbol of the arranged slot as a downlink symbol, the transmission in that slot is omitted for multi-slot PUSCH transmission. When repK is set, it can be set to one of the following values: 1, 2, 4, or 8. However, if the RRC parameter itself does not exist, the number of repetitions is set to 1 for transmission. In addition, repK-RV can be set to one of the following values: {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 at least some of the composed coded bits are different. In NR Release 16, inter-slot repetition is named PUSCH repetition type B. In the Release 16 specification, for PUSCH repetition type B, after determining the invalid symbols for each of K nominal repetitions, the remaining symbols are considered as potential valid symbols for PUSCH repetition type B. If the number of potential valid symbols for PUSCH repetition type B is greater than 0 for a nominal repetition, the nominal repetition constitutes one or more actual repetitions. Here, each actual repetition constitutes a set of consecutive potential valid symbols that may be used for PUSCH repetition type B in one slot. An actual repetition consisting of one symbol is omitted except when the symbol length L is 1. An actual repetition is omitted according to a specific condition. The redundancy version applied to the nth actual repetition (by counting including the omitted actual repetition) is determined according to a table in the specification.

If DMRS sharing (DMRS bundling) under consideration in 3GPP is applied, it becomes possible to share DMRS between the above slots, but if DMRS sharing is applied to all transmission slots, there is a problem that the terminal cannot change the phase of the transmission signal. Therefore, the solution to the above problem is shown below. When the setting related to DMRS sharing is transmitted by RRC signaling or signaling by DCI and the setting related to DMRS sharing is performed in the terminal, information on the time domain slot of DMRS is notified to the terminal device by separate signaling by RRC signaling or DCI. The terminal device transmits so that DMRS sharing can be applied by the base station device, which is the receiver, during the number of slots determined by the information on the time domain slot from the initial transmission slot. In other words, the transmission is performed so that it can be considered as QCL (Quasi-Colocation). In other words, the transmission is performed so that the amplitude and phase of the propagation path do not change between slots (so that it does not become discontinuous). FIG. 4 is a diagram for explaining a case where the number of repeated transmissions is 4, and two slots are set as the DMRS sharing period by higher layer signaling such as RRC. In the case of the figure, the transmitting device performs transmission with DMRS sharing in the first and second slots, and further performs transmission with DMRS sharing in the third and fourth slots. In this case, the second slot and the third slot are consecutive slots, but DMRS sharing cannot be applied. In addition, in the case where the four-time repeated transmission is applied, even if the terminal device does not perform the first transmission, starts transmission from the second time, and performs a total of three repeated transmissions up to the fourth repetition, the slot that satisfies the QCL is determined based on the repetition number specified by the base station, not the actual transmission. However, if it is specified by separate control information, the count may be started from the actual transmission. In addition, the slots specified by the information on the time domain slots may be transmitted so that non-consecutive slots are QCL, rather than consecutive slots. In addition, whether transmission from the first assigned repetition other than the first one is possible or not may be set by RRC signaling.

In NR, intra-slot frequency hopping/inter-slot frequency hopping/inter-repetition frequency hopping are specified, but if DMRS sharing is applied to the hopped frequency, the transmission characteristics generally deteriorate significantly in a frequency selective fading environment. Therefore, when the above hopping is applied by RRC signaling, etc., even if the hopping offset is 0, DMRS sharing may not be applied regardless of the setting of RRC signaling regarding DMRS sharing. Note that DMRS sharing may be applied at each hopped frequency, rather than not being applied completely. That is, for example, in FIG. 5 showing an example of inter-slot hopping and inter-slot repeated transmission, DMRS sharing may be applied to the first and third slots, and the second and fourth slots, which use the same frequency.

Although the above explanation assumes inter-slot repetition, it is not limited to inter-slot repetition and may be applied to intra-slot repetition. In this case, the setting regarding DMRS sharing by RRC signaling or DCI signaling is based on the repetition unit, that is, the number of repetitions within a slot, rather than the slot. Furthermore, the QCL may be limited to one slot of intra-slot repetition, and repetition outside the slot may not be considered as a QCL.

When DMRS sharing is possible, channel compensation can be performed using DMRS included in other slots, so it is not necessary to insert DMRS into the slot. If DMRS is not inserted, many information bits or parity bits can be transmitted, so the communication error rate can be reduced, leading to improved quality or coverage. For example, when a setting for reducing DMRS is made by control information such as RRC signaling, many information bits or parity bits can be transmitted by inserting DMRS only in the first repetition and not inserting DMRS in the second and subsequent repetitions. However, if transmission is started from the second repetition among the repetitions specified by the base station device, DMRS will not be transmitted. A configuration is adopted in which DMRS is placed only in slots (repetitions) with RV 0, and DMRS is not placed in slots (repetitions) with RV other than 0. The above will be explained using FIG. 6. The upper part of FIG. 6 shows the case where the RV pattern in the repeated transmission is {0, 0, 0, 0}. The figure shows a 4-slot repetition, with the DMRS symbols in the slots shown with diagonal lines and the data OFDM symbols with dotted patterns. When the RV pattern is {0, 0, 0, 0}, DMRS is transmitted in all slots. Next, when the RV pattern is {0, 3, 0, 3}, DMRS is transmitted in the first and third slots, and DMRS is not included in the second and fourth slots. When the RV pattern is {0, 2, 3, 1}, DMRS is transmitted only in the first slot, and DMRS is not included in the second, third, and fourth slots. In other words, since it is not specified in NR to start repeated transmission from a slot (repetition) with RV other than 0, transmission will always start from a slot with RV = 0. This makes it possible to avoid only transmission that does not include DMRS. Here, a configuration is set in which DMRS is not included in slots with RV other than 0, but rather than being completely not included, it may be reduced. For example, only the front-loaded DMRS may be transmitted, and all or part of the additional DMRS set by the RRC may be reduced. Information regarding the reduction criteria may be notified by RRC signaling. However, if the above transmission is performed when intra-slot frequency hopping/inter-slot frequency hopping/inter-repetition frequency hopping is applied, there is a problem that the DMRS will not be transmitted in the hop with the offset. Therefore, when any of the above frequency hopping is applied, the DMRS may be configured to be transmitted every repetition (slot) even when the DMRS sharing is set by the RRC and the DMRS sharing is enabled. In addition, with regard to the DMRS reduction, information regarding the time domain slot of the DMRS may be notified by RRC signaling or signaling by DCI, and the reduction may be applied every set slot (repetition), and the DMRS may be transmitted outside the set slot.

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

The receiving unit 212 is composed of a radio receiving unit (radio receiving step) 2120, a multiplexing/demultiplexing unit (multiplexing/demultiplexing step) 2122, a propagation path estimation unit (propagation path estimation step) 2144, an equalization unit (equalization step) 2126, a demodulation unit (demodulation step) 2128, and a decoding unit (decoding step) 2130.

The wireless receiver 2120 converts the downlink signal received via the receiving antenna 210 into a baseband signal by down-conversion, removes unnecessary frequency components, controls the amplification level so that the signal level is appropriately maintained, performs quadrature demodulation based on the in-phase and quadrature components of the received signal, and converts the quadrature demodulated analog signal into a digital signal. The wireless receiver 2120 removes the portion corresponding to the CP from the converted digital signal, performs FFT on the signal from which the CP has been removed, and extracts the signal in the frequency domain.

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

The equalization unit 2126 generates equalization weights based on the MMSE standard from the frequency response input from the channel estimation unit 2124. The equalization unit 2126 multiplies the input signals (PUCCH, PDSCH, PBCH, etc.) from the multiplexing/demultiplexing unit 2122 by the equalization weights. The demodulation unit 2128 performs demodulation processing based on information on the modulation order that is predetermined/instructed by the control unit 204.

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

In the first embodiment, the criteria for DMRS sharing and the reduction of DMRS are explained assuming DMRS sharing. In the second embodiment, a method for reducing the error rate in repeated transmission without assuming DMRS sharing is explained.

In configured grant scheduling type 2, the allocation period, number of repetitions, etc. are set by RRC signaling, and the settings of the remaining transmission parameters (MCS and resource blocks to be used) are notified by PDCCH (DCI), and configured grant scheduling type 2 is activated. After that, transmission is generally performed with the same settings for a while. To deactivate configured grant scheduling type 2, certain parameters of PDCCH (DCI) are set to certain values and notified to the terminal device.

As described above, in configured grant scheduling type 2, the parameters set in the PDCCH continue to be used for a certain period of time. If the situation changes significantly, the parameters can be changed by reactivating the PDCCH by transmitting it again. However, after the change, the transmission parameters set by the PDCCH will continue to be used for a certain period of time. In particular, when a terminal has multiple antenna ports, the optimal values for information regarding pre-coding (beamforming) are prone to change, making it difficult to set optimal values when there is a time difference between the time the PDCCH is transmitted and the time the actual data is transmitted.

Therefore, in the repeated transmission in configured grant scheduling, it is possible to apply different precoding for each repetition. That is, when configured grant scheduling type 2 is configured by RRC and DCI, if a separate setting related to precoding cycling is applied by RRC signaling, a specified precoding index is used for the first transmission, and for the second and subsequent repetitions, different precoding is applied according to a precoding pattern set in advance. However, one precoding pattern may be specified, or a base station may specify a precoding pattern from among multiple patterns by control information. Also, when configured by RRC, the notified precoding may not be used, and the precoding determined by the terminal device may be used. In this case, it may be restricted to apply the same precoding.
Third Embodiment

The number of spatial multiplexing in NR is a maximum of 8 for DMRS configuration 1 and a maximum of 12 for DMRS configuration 2. This is because DMRS (front loaded DMRS) can only be placed in two consecutive OFDM symbols. Up until NR Rel-16, there was a problem that allocating DMRS to three or more consecutive OFDM symbols limited the OFDM symbols (resource elements) that could be used for data transmission, resulting in a reduced transmission rate.

If DMRS sharing can be applied in NR Rel-17, even if the proportion of DMRS becomes high in one repeated transmission, if DMRS can be reduced in the second and subsequent repetitions, spatial multiplexing can be increased without increasing the proportion of DMRS overall.

To achieve the above, even if an RRC parameter (1 or 2) for setting the number of frontloaded DMRSs up to Rel16 is set, if an RRC parameter (an integer of 3 or more) for Rel-17 is set, the DMRSs are arranged according to the RRC parameter (an integer of 3 or more). However, this is not limited to the above, and for example, the number of frontloaded DMRSs in the RRC parameter for Rel-16 may be multiplied by the number set in the RRC parameter set in Rel-17 to determine the true number of DMRSs. In addition, there may be separate restrictions when intra-slot frequency hopping or intra-slot repetition (transmission) is applied. This is because applying the above technology reduces the number of consecutively allocated OFDM symbols, which causes the insertion loss of DMRS to become too large, or makes it impossible to arrange all of the DMRS symbols set in the allocation in the first place.

A program that operates on an apparatus according to one aspect of the present invention may be a program that controls a Central Processing Unit (CPU) or the like to cause a computer to function so as to realize the functions of the above-described embodiment according to one aspect of the present invention. The program or information handled by the program is temporarily loaded into a volatile memory such as a Random Access Memory (RAM) during processing, or is stored in a non-volatile memory such as a flash memory or a Hard Disk Drive (HDD), and is read, modified, and written by the CPU as necessary.

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

Furthermore, "computer-readable recording medium" may also include something that dynamically stores a program for a short period of time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, or something that stores a program for a fixed period of time, such as volatile memory within a computer system that serves as a server or client in such cases. The above program may also be one that realizes part of the functions described above, or one that can realize the functions described above in combination with a program already recorded in the computer system.

In addition, each functional block or feature of the device used in the above-mentioned embodiment may be implemented or executed by an electric circuit, i.e., typically an integrated circuit or a plurality of integrated circuits. The electric circuit designed to execute the functions described herein may include a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or a combination thereof. The general-purpose processor may be a microprocessor, or may be a conventional processor, controller, microcontroller, or state machine. The electric circuit described above may be composed of a digital circuit or an analog circuit. In addition, when a technology for integrated circuitization that replaces the current integrated circuit emerges due to the progress of semiconductor technology, it is also possible to use an integrated circuit based on that technology.

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

Although an embodiment of the present invention has been described above in detail with reference to the drawings, the specific configuration is not limited to this embodiment, and design modifications and the like that do not depart from the gist of the present invention are also included. Furthermore, various modifications of one aspect of the present invention are possible within the scope of the claims, and embodiments obtained by appropriately combining the technical means disclosed in different embodiments are also included in the technical scope of the present invention. Also included are configurations in which elements described in the above embodiments are substituted for elements that have the same effect.

One aspect of the present invention is suitable for use in base station equipment, terminal equipment and communication methods.

10 Base station device 20 Terminal device 10a Range in which the base station device 10 can connect to the terminal device 102 Upper layer processing unit 104 Control unit 106 Transmitter 108 Transmitting antenna 110 Receiving antenna 112 Receiving unit 1060 Encoder 1062 Modulator 1064 Downlink control signal generator 1066 Downlink reference signal generator 1068 Multiplexer 1070 Radio transmitter 1120 Radio receiver 1122 Propagation path estimator 1124 Demultiplexer 1126 Equalizer 1128 Demodulator 1130 Decoder 202 Upper layer processing unit 204 Control unit 206 Transmitter 208 Transmitting antenna 210 Receiving antenna 212 Receiving unit 2060 Encoder 2062 Modulator 2064 Uplink reference signal generator 2066 Uplink control signal generator 2068 Multiplexer 2070 Radio transmitting unit 2120, radio receiving unit 2122, demultiplexing unit 2124, propagation path estimating unit 2126, equalization unit 2128, demodulation unit 2130, decoding unit

Claims (6)

A terminal device that communicates with a base station device through repeated transmission, comprising an upper layer processing unit that sets the number of repetitions in the repeated transmission and the redundancy version in the repeated transmission, and a slot configuration unit that configures slots, the slot configuration unit changing the number of reference signals in each repeated transmission based on the redundancy version in the repeated transmission. A terminal device as described in claim 1, wherein the slot configuration unit includes a smaller number of reference signals in a repeated transmission in which a value other than 0 is set as the redundancy version than in a repeated transmission in which 0 is set as the redundancy version. A terminal device as described in claim 1, wherein the slot configuration unit transmits a reference signal only in repeated transmissions in which the redundancy version is set to 0. A base station device that communicates with a terminal device through repeated transmission, comprising an upper layer processing unit that sets the number of repetitions in the repeated transmission and the redundancy version in the repeated transmission, and a slot configuration unit that configures slots, the slot configuration unit changing the number of reference signals in each repeated transmission based on the redundancy version in the repeated transmission. A base station device as described in claim 4, wherein the slot configuration unit includes a smaller number of reference signals in a repeated transmission in which a value other than 0 is set as the redundancy version than in a repeated transmission in which 0 is set as the redundancy version. A base station device as described in claim 4, wherein the slot configuration unit transmits a reference signal only in repeated transmissions in which the redundancy version is set to 0.

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