WO2025094902A1 - Terminal device and communication method - Google Patents

Abstract

This terminal device, if applying a multi-channel access procedure to perform a plurality of sidelink transmissions with a plurality of channels in one or more consecutive slots, selects the highest channel access priority class value among a plurality of channel access priority class values related to the plurality of sidelink transmissions, and uses that channel access priority class value selected in the multi-channel access procedure for a channel in which a Type 1 channel access procedure is performed.

Description

Terminal device and communication method

The present invention relates to a terminal device and a communication method.
This application claims priority to Japanese Patent Application No. 2023-188071, filed in Japan on November 2, 2023, the contents of which are incorporated herein by reference.

A radio access method and radio network for cellular mobile communications (hereinafter referred to as "Long Term Evolution (LTE)" or "EUTRA: Evolved Universal Terrestrial Radio Access") is being studied by the 3rd Generation Partnership Project (3GPP: 3rd Generation Partnership Project). In LTE, base station equipment is also called eNodeB (evolved NodeB), and terminal equipment is also called UE (User Equipment). LTE is a cellular communication system in which the areas covered by base station equipment are arranged in multiple cell-like configurations. A single base station equipment may manage multiple serving cells.

3GPP is currently studying and standardizing the next-generation standard (NR: New Radio) as the communications method for 5G. NR is expected to meet the requirements for three scenarios within a single technology framework: eMBB (enhanced Mobile BroadBand), mMTC (massive Machine Type Communication), and URLLC (Ultra Reliable and Low Latency Communication).

NR supports sidelink technology, which allows terminal devices to communicate directly with each other without going through a base station. In addition, the application of sidelink technology in unlicensed spectrum is being considered (Non-Patent Document 1).

"Title: New WID on NR sidelink evolution", RP-213678, OPPO, LG Electronics. 3GPP TSG RAN Meeting #94e, Dec.6-17, 2021

In unlicensed bands, LBT (Listen Before Talk) based on CCA (Clear Channel Assessment) is used to coexist with other systems. In Japan, Europe, and other countries, the LBT function is required for systems operating in the unlicensed 5 GHz band.
An object according to one aspect of the present invention is to provide a terminal device capable of realizing fair channel access and a communication method used in the terminal device.

(1) A first aspect of the present invention is a terminal device comprising a processor and a memory for storing computer program code, the terminal device performing operations including applying a multi-channel access procedure for performing multiple sidelink transmissions on multiple channels in one or more consecutive slots, selecting a maximum channel access priority class value among multiple channel access priority class values associated with the multiple sidelink transmissions, and using the channel access priority class value selected in the multi-channel access procedure on a channel on which a Type 1 channel access procedure is performed.

(2) A second aspect of the present invention is a communication method for use in a terminal device, comprising the steps of: applying a multi-channel access procedure to perform multiple sidelink transmissions on multiple channels in one or more consecutive slots; selecting a maximum channel access priority class value among multiple channel access priority class values associated with the multiple sidelink transmissions; and using the channel access priority class value selected in the multi-channel access procedure on a channel on which a Type 1 channel access procedure is performed.

Fair channel access can be achieved.

1 is a conceptual diagram of a wireless communication system according to an embodiment of the present invention. FIG. 2 is a schematic diagram illustrating an example of a resource grid in a subframe according to an aspect of the present embodiment. 1 is a schematic block diagram showing a configuration of a terminal device 1 according to an aspect of the present embodiment. 1 is a schematic block diagram showing a configuration of a base station device 3 according to one aspect of the present embodiment. FIG. 2 is a diagram illustrating an example of interlace mapping according to an aspect of this embodiment. A figure showing an example of an arrangement of PSCCHs monitored in a terminal device 1 according to one embodiment of the present invention. A figure showing an example of an arrangement of PSCCHs monitored in a terminal device 1 according to one embodiment of the present invention. A figure showing an example of a resource selection procedure in a terminal device 1 relating to one aspect of this embodiment. A figure showing an example of the arrangement of slots of MCSt of a terminal device 1 according to one embodiment of the present invention. A figure showing an example of an arrangement of consecutive slot transmissions including multiple sidelink transmissions of a terminal device 1 according to one aspect of this embodiment. A figure showing an example of sidelink transmission in multiple channels of a terminal device 1 according to one aspect of this embodiment. A diagram showing multiple sidelink transmissions in multiple channels in consecutive slots of a terminal device 1 in one embodiment of the present invention. A figure showing an example of processing of a multi-channel access procedure for performing multiple sidelink transmissions in multiple channels in one or more consecutive slots of a terminal device 1 according to one embodiment of this invention.

The following describes an embodiment of the present invention.

"A and/or B" may be a term including "A", "B", or "A and B".

A parameter or information indicating one or more values may mean that the parameter or information at least includes a parameter or information indicating the one or more values. The upper layer parameter may be a single upper layer parameter. The upper layer parameter may be an information element (IE) including multiple parameters.

FIG. 1 is a conceptual diagram of a wireless communication system according to one aspect of this embodiment. In FIG. 1, the wireless communication system includes terminal devices 1A to 1C and a base station device 3 (gNB). Hereinafter, terminal devices 1A to 1D are also referred to as terminal device 1 (UE).

The base station device 3 may be configured to include one or both of an MCG (Master Cell Group) and an SCG (Secondary Cell Group). The MCG is a group of serving cells including at least a PCell (Primary Cell). The SCG is a group of serving cells including at least a PSCell (Primary Secondary Cell). The PCell is a cell on which an initial connection establishment procedure or a connection re-establishment procedure is performed by the terminal device 1. The PSCell is a serving cell on which a random access procedure is performed by the terminal device 1. The MCG may be configured to include one or more SCells (Secondary Cells). The SCG may be configured to include one or more SCells. The serving cell identity is a short identifier for identifying a serving cell. The serving cell identity may be given by an upper layer parameter.

Serving cell group (cell group) is a general term for MCG, SCG, and PUCCH cell group. A serving cell group may include one or more serving cells (or component carriers). One or more serving cells (or component carriers) included in a serving cell group may be operated by carrier aggregation.

The base station device 3 communicates with the terminal device 1 using different frequency bands (carrier frequencies, frequency spectrums). This operation (multi-carrier operation) may be called carrier aggregation or dual connectivity. Different cells (serving cells) use different frequency bands. In the base station device 3 and the terminal device 1, the multiple cells used in carrier aggregation may be such that one cell uses the downlink frequency band and the uplink frequency band, and the other cells use only the downlink frequency band, or the other cells may also use the downlink frequency band and the uplink frequency band. The terminal device 1 makes an initial connection with the base station device 3, and after the connection with the base station device 3 is established, multiple cell connections are added. The terminal device 1 is added with a frequency band used for communication. The terminal device 1 is added with a cell (serving cell) used for communication. The terminal device 1 is added with a connection to the base station device 3.

Terminal device 1A and terminal device 1B communicate directly using side link technology. Terminal device 1A and terminal device 1B are located within the coverage of base station device 3 (in-coverage). Terminal device 1A and terminal device 1C communicate directly using side link technology. Terminal device 1C and terminal device 1D communicate directly using side link technology. Terminal device 1C and terminal device 1D are located outside the coverage of base station device 3 (out-of-coverage). There are three cases: direct communication between in-coverage terminal devices 1, direct communication between in-coverage terminal device 1 and out-of-coverage terminal device 1, and direct communication between out-of-coverage terminal devices 1.

In a wireless communication system, the terminal device 1 and the base station device 3 may use one or more communication methods. For example, CP-OFDM (Cyclic Prefix-Orthogonal Frequency Division Multiplex) may be used in the downlink of the wireless communication system. Also, either CP-OFDM or DFT-s-OFDM (Discrete Fourier Transform-spread-Orthogonal Frequency Division Multiplex) may be used in the uplink of the wireless communication system. Here, DFT-s-OFDM is a communication method in which transform precoding is applied prior to signal generation in CP-OFDM. Here, transformed precoding is also referred to as DFT precoding.

CP-OFDM may be used for the side link between terminal device 1 and terminal device 1. Also, DFT-s-OFDM may be used for the side link between terminal device 1 and terminal device 1.

As shown in FIG. 1, the base station device 3 may be configured with one transceiver device (or a transmission point, a transmitting device, a receiving point, a receiving device, a transceiver point). On the other hand, in some cases, the base station device 3 may be configured to include multiple transceivers. When the base station device 3 is configured with multiple transceivers, each of the multiple transceivers may be located in a different geographical location.

The subcarrier spacing (SCS: SubCarrier Spacing) Δf for a certain subcarrier spacing setting μ may be Δf = 2μ × 15kHz. For example, the subcarrier spacing setting μ may indicate any of 0, 1, 2, 3, or 4.

A time unit Tc=1/(Δfmax×Nf) may be used to express the length of the time domain. Here, Δfmax=480 kHz. Nf=4096. The constant κ may be κ=Δfmax×Nf/(ΔfrefNf,ref)=64. Δfref may be 15 kHz. Nf,ref
f is 2048.

The transmission of downlink/uplink signals may be organized into radio frames (system frames, frames) of length Tf, where Tf = (Δfmax × Nf/100) × Ts = 10 ms.

The transmission of sidelink signals may be organized in radio frames (system frames, frames) of length Tf, where Tf = (Δfmax × Nf/100) × Ts = 10 ms.

The radio frame may be configured to include 10 subframes. Here, the length of the subframe may be Tsf = (Δfmax × Nf/1000) × Ts = 1 ms. In addition, the number of OFDM symbols per subframe may be Nsubframe, μsymb = Nslotsymb × Nsubframe, μslot.

The OFDM symbol is used as the unit of time domain for the communication method used in the wireless communication system. For example, the OFDM symbol may be used as the unit of time domain for CP-OFDM. The OFDM symbol may also be used as the unit of time domain for DFT-s-OFDM.

A slot may be composed of multiple OFDM symbols. For example, one slot may be composed of Nslotsymb consecutive OFDM symbols. For example, in a normal CP setting, Nslotsymb = 14. Also, in an extended CP setting, Nslotsymb = 12.

The slots may be indexed in the time domain. For example, the slot index nμs may be given in ascending order as integer values ranging from 0 to Nsubframe,μslot-1 in the subframe. Also, the slot index nμs,f may be given in ascending order as integer values ranging from 0 to Nframe,μslot-1 in the radio frame.

FIG. 2 is a diagram showing an example of the configuration of a resource grid according to one aspect of this embodiment. In the resource grid of FIG. 2, the horizontal axis is the OFDM symbol index lsym, and the vertical axis is the subcarrier index ksc. The resource grid of FIG. 2 includes Nsize, μgrid, x × NRBsc subcarriers, and Nsubframe, μsymb OFDM symbols. Here, Nsize, μgrid, x indicate the bandwidth of the SCS-specific carrier. The values of Nsize, μgrid, x are expressed in units of resource blocks.

Within the resource grid, a resource identified by the subcarrier index ksc and the OFDM symbol index lsym is also called a resource element (RE: ResourceElement).

A resource block (RB) contains NRBsc consecutive subcarriers. Resource block is a general term for common resource blocks (CRBs), physical resource blocks (PRBs), and virtual resource blocks (VRBs). For example, NRBsc may be 12.

A BandWidth Part (BWP) may be configured as a subset of the resource grid.
Here, the BWP set for the downlink is also called a downlink BWP, and the BWP set for the uplink is also called an uplink BWP.

The BWP set for a sidelink is also called a sidelink BWP.

Carrier aggregation may be performing communication using multiple aggregated serving cells. Also, carrier aggregation may be performing communication using multiple aggregated component carriers. Also, carrier aggregation may be performing communication using multiple aggregated downlink component carriers. Also, carrier aggregation may be performing communication using multiple aggregated uplink component carriers.

Below, an example configuration of a terminal device 1 according to one aspect of this embodiment is described.

FIG. 3 is a schematic block diagram showing the configuration of a terminal device 1 according to one aspect of this embodiment. As shown in the figure, the terminal device 1 includes a radio transmission/reception unit 10 and an upper layer processing unit 14. The radio transmission/reception unit 10 includes at least an antenna unit 11, an RF (Radio Frequency) unit 12, and part or all of a baseband unit 13. The upper layer processing unit 14 includes at least a medium access control layer processing unit 15, and part or all of a radio resource control layer processing unit 16. The radio transmission/reception unit 10 is also referred to as a transmitting unit, a receiving unit, or a physical layer processing unit.

The wireless transceiver unit 10 performs physical layer processing.

For example, the radio transceiver unit 10 may generate a baseband signal of an uplink physical channel. Here, a transport block delivered from a higher layer on the UL-SCH may be arranged on the uplink physical channel. For example, the radio transceiver unit 10 may generate a baseband signal of an uplink physical signal.

For example, the wireless transceiver 10 may attempt to detect information transmitted by a downlink physical channel. Here, a transport block of the information transmitted by the downlink physical channel may be delivered to a higher layer on DL-SCH. For example, the wireless transceiver 10 may attempt to detect information transmitted by a downlink physical signal.

For example, the wireless transceiver unit 10 may generate a baseband signal of a sidelink physical channel. For example, the wireless transceiver unit 10 may generate a baseband signal of a sidelink physical signal. For example, the wireless transceiver unit 10 may attempt to detect information transmitted by the sidelink physical channel. For example, the wireless transceiver unit 10 may attempt to detect information transmitted by the sidelink physical signal.

The receiving unit of the terminal device 1 receives the PDCCH. The receiving processing unit of the terminal device 1 performs processing to receive the PDCCH in the downlink frequency band (cell, component carrier, carrier). The receiving processing unit of the terminal device 1 performs processing such as demodulation and decoding on the PDCCH. The receiving processing unit of the terminal device 1 performs processing to receive the PDCCH and performs processing to detect downlink control information.

The receiving unit of the terminal device 1 receives the PDSCH. The receiving processing unit of the terminal device 1 performs processing to receive the PDSCH in the downlink frequency band (cell, component carrier, carrier). The receiving processing unit of the terminal device 1 performs processing such as demodulation and decoding on the PDSCH.

The receiving unit of the terminal device 1 receives the PSCCH. The receiving processing unit of the terminal device 1 performs processing such as demodulation and decoding on the PSCCH. The receiving processing unit of the terminal device 1 performs processing to receive the PSCCH and to detect side link control information. The receiving unit of the terminal device 1 determines the frequency resources (interlaces and resource blocks described later) that constitute the PSCCH. The receiving unit of the terminal device 1 determines the OFDM symbol in which the PSCCH may be placed. The receiving unit of the terminal device 1 blind decodes the PSCCH. The receiving unit of the terminal device 1 blind decodes the PSCCH in one slot in one resource pool. The receiving unit of the terminal device 1 may blind decode the PSCCH in two or more slots in one resource pool. The receiving unit of the terminal device 1 may blind decode two or more PSCCHs in one slot in one resource pool. The receiving unit of the terminal device 1 receives the PSSCH. The receiving processing unit of the terminal device 1 performs processing such as demodulation and decoding on the PSSCH. The receiving unit of terminal device 1 receives the PSFCH. The receiving processing unit of terminal device 1 receives the HARQ-ACK on the PSFCH.

The transmitting unit (also referred to as the transmission processing unit) of the terminal device 1 transmits a HARQ-ACK. The transmitting processing unit of the terminal device 1 transmits a HARQ-ACK for the PDSCH. The transmitting processing unit of the terminal device 1 transmits a HARQ-ACK in the uplink frequency band (cell, component carrier, carrier).

The transmission processing unit of the terminal device 1 transmits a HARQ-ACK for the PSSCH. The transmission processing unit of the terminal device 1 transmits a HARQ-ACK in the sidelink frequency band. The transmission processing unit of the terminal device 1 transmits a HARQ-ACK on the PSFCH. The transmission processing unit of the terminal device 1 may transmit a HARQ-ACK on the PSSCH. The transmission processing unit of the terminal device 1 may not transmit a HARQ-ACK for the PSSCH.

The transmission unit of the terminal device 1 transmits the PSCCH. The transmission processing unit of the terminal device 1 performs processing such as encoding and modulation on the PSCCH. The transmission processing unit of the terminal device 1 performs processing to transmit side link control information using the PSCCH. The transmission unit of the terminal device 1 determines the frequency resources (interlaces and resource blocks described below) that constitute the PSCCH. The transmission unit of the terminal device 1 determines the OFDM symbol in which the PSCCH can be placed. The transmission unit of the terminal device 1 transmits the PSSCH. The transmission processing unit of the terminal device 1 performs processing such as encoding and modulation on the PSSCH.

The upper layer processing unit 14 outputs uplink data (transport blocks) generated by user operations, etc., to the wireless transceiver unit 10. The upper layer processing unit 14 processes the MAC layer, Packet Data Convergence Protocol (PDCP) layer, Radio Link Control (RLC) layer, and RRC layer.

The upper layer processing unit 14 outputs the side link data (transport block) to the radio transceiver unit 10.

The media access control layer processing unit (MAC layer processing unit) 15 provided in the upper layer processing unit 14 performs MAC layer processing.

The radio resource control layer processing unit 16 included in the upper layer processing unit 14 performs RRC layer processing. The radio resource control layer processing unit 16 manages various setting information/parameters (RRC parameters) of its own device. The radio resource control layer processing unit 16 sets various setting information/parameters (RRC parameters) based on upper layer signals received from the base station device 3. That is, the radio resource control layer processing unit 16 sets various setting information/parameters (RRC parameters) based on information indicating the various setting information/parameters (RRC parameters) received from the base station device 3. The setting information may include information related to processing or setting of physical channels and physical signals (i.e., the physical layer), the MAC layer, the PDCP layer, the RLC layer, and the RRC layer. The parameters may be upper layer parameters.

For example, the radio resource control layer processing unit 16 may acquire RRC parameters contained in an RRC message on a certain logical channel, and set the acquired RRC parameters in a memory area of the terminal device 1. The RRC parameters set in the memory area of the terminal device 1 may be provided to a lower layer.

The radio resource control layer processing unit 16 sets a control resource set based on the RRC signaling received from the base station device 3. The radio resource control layer processing unit 16 sets (configures) a search space in the control resource set. The radio resource control layer processing unit 16 sets (configures) PDCCH candidates to be monitored in the control resource set. The radio resource control layer processing unit 16 sets (configures) the number of PDCCH candidates to be monitored in the control resource set. The radio resource control processing unit 16 sets (configures) an aggregation level of the PDCCH candidates to be monitored in the control resource set.

The radio resource control layer processing unit 16 sets the DCI format to be monitored within the control resource set. The radio resource control layer processing unit 16 may set the DCI format to be monitored within the search area. The radio resource control layer processing unit 16 sets the DCI format to be monitored within the control resource set based on the RRC signaling indicated from the base station device 3. The radio resource control layer processing unit 16 may set the DCI format to be monitored within the search area based on the RRC signaling indicated from the base station device 3. The radio resource control layer processing unit 16 sets one or more DCI formats to be monitored in the reception processing unit.

The radio resource control layer processing unit 16 performs settings related to multiple search areas. Each setting related to the multiple search areas is indexed.

The radio resource control layer processing unit 16 performs settings related to CSI feedback (transmission of channel state information) based on the RRC signaling received from the base station device 3. The radio resource control layer processing unit 16 sets the CSI feedback transmission period, the CSI feedback transmission start timing (offset), the CSI feedback information type, and the like. The radio resource control layer processing unit 16 performs settings related to multiple CSI feedbacks. The settings related to multiple CSI feedbacks are each indexed.

The radio resource control layer processing unit 16 performs settings related to the SPS based on the RRC signaling received from the base station device 3. The radio resource control layer processing unit 16 sets the period of the SPS resources (PDSCH resources), the start timing (offset) of the SPS resources (PDSCH resources), the number of HARQ processes set for the SPS, the offset used to derive the HARQ process ID used for the SPS, the RNTI value for scheduling the SPS, and the like. The radio resource control layer processing unit 16 performs settings related to multiple SPS. The settings related to multiple SPS are each indexed.

The radio resource control layer processing unit 16 configures carrier aggregation based on the RRC signaling received from the base station device 3. The radio resource control layer processing unit 16 configures a serving cell (secondary cell, primary secondary cell) as the carrier aggregation configuration. The serving cell may be configured with a downlink component carrier. The serving cell may be configured with a downlink component carrier and an uplink component carrier. The radio resource control layer processing unit 16 controls the radio transmission/reception unit 10 to perform reception processing with the downlink component carrier configured in the carrier aggregation configuration. The radio resource control layer processing unit 16 controls the radio transmission/reception unit 10 to perform transmission processing with the uplink component carrier configured in the carrier aggregation configuration.

The radio resource control layer processing unit 16 performs settings related to the side link based on the RRC signaling received from the base station device 3. The radio resource control layer processing unit 16 sets parameters related to the side link notified from the base station device 3. The parameters related to the side link are described below. For example, the radio resource control layer processing unit 16 sets the OFDM symbol in which the PSCCH can be placed. For example, the radio resource control layer processing unit 16 sets the band in which the PSCCH is placed. For example, the radio resource control layer processing unit 16 sets the number of resource blocks or interlaces that make up one PSCCH. The radio resource control layer processing unit 16 performs settings related to the transmission and reception of the PSCCH for the radio transmission and reception unit 10.

The medium access control layer processing unit (MAC layer processing unit) 15 activates/deactivates the secondary cell based on the MAC CE (MAC Control Element) received from the base station device 3. The medium access control layer processing unit (MAC layer processing unit) 15 outputs information indicating activation/deactivation for multiple serving cells configured by the radio resource control layer processing unit 16 to the radio transceiver unit 10 based on the MAC CE (SCell Activation/Deactivation MAC CEs) including information on activation/deactivation of the secondary cell. The medium access control layer processing unit (MAC layer processing unit) 15:
The deactivation of the secondary cell is performed based on a timer. The medium access control layer processing unit (MAC layer processing unit) 15 determines that the base station device 3 has not performed scheduling for the serving cell for a certain period of time by measuring with a timer, and deactivates the serving cell and controls the radio transceiver unit 10.

The medium access control layer processing unit (MAC layer processing unit) 15 processes sidelink HARQ operations, sidelink scheduling requests, sidelink buffer status reports, and CSI reports.

The radio resource control layer processing unit 16 may include functional information generated based on the functions of the terminal device 1 in an RRC message and transmit the information to the base station device 3.

The wireless transceiver 10 performs modulation, encoding, and transmission processing. The wireless transceiver 10 generates a physical signal by encoding data (transport block), modulating it, and generating a baseband signal (converting it into a time-continuous signal), and transmits the physical signal to the base station device 3.

The wireless transceiver unit 10 performs demodulation, decoding, and reception processing. The wireless transceiver unit 10 outputs the transport block of the information detected based on the demodulation and decoding processing of the received physical signal to the upper layer processing unit 14 on the DL-SCH.

The wireless transceiver unit 10 stops various reception processes and various transmission processes in the deactivated serving cell. For example, the wireless transceiver unit 10 stops monitoring the PDCCH in the deactivated serving cell. For example, the wireless transceiver unit 10 stops receiving the PDSCH in the deactivated serving cell. For example, the wireless transceiver unit 10 stops transmitting the SRS in the deactivated serving cell. For example, the wireless transceiver unit 10 stops transmitting the PUSCH in the deactivated serving cell.

The RF unit 12 converts the signal received via the antenna unit 11 into a baseband signal (down-converts) and removes unnecessary frequency components. The RF unit 12 outputs the baseband signal to the baseband unit 13.

The baseband unit 13 converts the analog signal input from the RF unit 12 into a digital signal. The baseband unit 13 removes the portion corresponding to the CP (Cyclic Prefix) from the converted digital signal. The baseband unit 13 performs a fast Fourier transform (FFT) on the signal from which the CP has been removed, and extracts the signal in the frequency domain.

The baseband unit 13 performs an Inverse Fast Fourier Transform (IFFT) on the physical signal to generate an OFDM symbol. The baseband unit 13 adds a CP to the generated OFDM symbol to generate a baseband digital signal. The baseband unit 13 converts the baseband digital signal into an analog signal. The baseband unit 13 outputs the converted analog signal to the RF unit 12.

The RF unit 12 uses a low-pass filter to remove unnecessary frequency components from the analog signal input from the baseband unit 13, and upconverts the analog signal to a carrier frequency to generate an RF signal. The RF unit 12 transmits the RF signal via the antenna unit 11. The RF unit 12 also amplifies the power. The RF unit 12 may also have a function of controlling the transmission power. The RF unit 12 is also referred to as a transmission power control unit.

The wireless transceiver 10 performs carrier sensing (LBT) before transmitting a signal in order to avoid collision of signals with other devices. The following types of LBT are used:
Type 1: LBT with a random backoff process using a variable-sized contention window
Type 2A: LBT with no random backoff process, performing carrier sense for 25us before transmitting a signal
Type 2B: LBT with no random backoff process, performing carrier sensing for 16us before transmitting a signal
・Type 2C: LBT not performed

The wireless transceiver 10 transmits a signal after detecting in listening that no other devices are transmitting (idle state), and does not transmit a signal when detecting in listening that other devices are transmitting (busy state). The wireless transceiver 10 acquires a transmission opportunity and transmits when the LBT result is idle, and does not transmit when the LBT result is busy. The time of the transmission opportunity is called the Channel Occupancy Time (COT). In LBT, the terminal device 1 monitors the channel before transmitting data, evaluates the idle channel, and transmits data only when it is confirmed that the channel is in an idle state.

When performing a random backoff process, the wireless transmission/reception unit 10 randomly generates a backoff counter value within the range of the contention window size after the previous transmission. In random backoff, the terminal device 1 evaluates whether the channel is idle by detecting channel energy at each time interval using the random backoff counter. The wireless transmission/reception unit 10 waits until it is confirmed that the channel is idle for a certain period of time, and performs carrier sense (sensing) for each sensing slot time. If the result of the carrier sense shows that the channel is idle, the wireless transmission/reception unit 10 decreases the backoff counter value. If the result of the carrier sense shows that the channel is busy, the wireless transmission/reception unit 10 maintains the backoff counter value, waits until it is confirmed that the channel is idle for a certain period of time, and then performs carrier sense. After repeating the above operations, the wireless transmission/reception unit 10 obtains access to the channel after the backoff counter value becomes zero, and can start transmitting signals on that channel.

When HARQ-ACK feedback is applied to the sidelink, the wireless transceiver unit 10 updates the contention window size based on the status of the HARQ-ACK. If the status of the HARQ-ACK is ACK, the wireless transceiver unit 10 sets the contention window size to the minimum value. If the status of the HARQ-ACK is NACK, the wireless transceiver unit 10 sets the contention window size to the next largest value. If the contention window size reaches the maximum value that can be set, the wireless transceiver unit 10 continues to use the maximum value even if the status of the HARQ-ACK is NACK.

The initial value of the random backoff counter may be an integer between 0 and the contention window size. Before the random backoff counter is initialized, the contention window size is adjusted to control the average time required for terminal device 1 to access the channel.

Terminal device 1 performs listen-before-talk (LBT) on the channel before transmitting on the channel. Terminal device 1 may adjust the amount of time that it performs LBT. Terminal device 1 may select a random number between zero and the contention window size. If the channel is free for at least the amount of time associated with the random number, terminal device 1 gets a transmission opportunity and can transmit.

Below, an example configuration of a base station device 3 according to one aspect of this embodiment is described.

FIG. 4 is a schematic block diagram showing the configuration of a base station device 3 according to one aspect of this embodiment. As shown in the figure, the base station device 3 includes a radio transmission/reception unit 30 and a higher layer processing unit 34. The radio transmission/reception unit 30 includes an antenna unit 31, an RF (Radio Frequency) unit 32, and a baseband unit 33. The higher layer processing unit 34 includes a medium access control layer processing unit 35 and a radio resource control layer processing unit 36. The radio transmission/reception unit 30 is also referred to as a transmitting unit, a receiving unit, or a physical layer processing unit.

The upper layer processing unit 34 processes the MAC (Medium Access Control) layer, the Packet Data Convergence Protocol (PDCP) layer, the Radio Link Control (RLC) layer, and the Radio Resource Control (RRC) layer. Here, the MAC layer is also referred to as the MAC sublayer. The PDCP layer is also referred to as the PDCP sublayer. The RLC layer is also referred to as the RLC sublayer. The RRC layer is also referred to as the RRC sublayer.

The medium access control layer processing unit 35 provided in the upper layer processing unit 34 performs MAC layer processing. Here, the MAC layer processing may include mapping between logical channels and transport channels, multiplexing one or more MAC SDUs (Service Data Units) into transport blocks, decomposing a transport block delivered from the physical layer on the UL-SCH into one or more MAC SDUs, applying HARQ (Hybrid Automatic Repeat reQuest) to the transport block, and some or all of the processing of scheduling requests.

The radio resource control layer processing unit 36 included in the upper layer processing unit 34 performs RRC layer processing. The RRC layer processing may include some or all of the management of broadcast signals, management of RRC connection/RRC idle states, and RRC reconfiguration. The radio resource control layer processing unit 36 generates downlink data (transport blocks), system information, RRC messages, MAC CE, etc. that are placed in the PDSCH, or obtains them from the upper node, and outputs them to the radio transceiver unit 30.

The radio resource control layer processing unit 36 also manages various setting information/parameters (RRC parameters) for each terminal device 1. The radio resource control layer processing unit 36 may set various setting information/parameters for each terminal device 1 via a higher layer signal. That is, the radio resource control layer processing unit 36 transmits/reports information indicating various setting information/parameters. The setting information may include information related to processing or setting of a physical channel or physical signal (i.e., the physical layer), the MAC layer, the PDCP layer, the RLC layer, and the RRC layer. The parameters may be higher layer parameters. For example, the radio resource control layer processing unit 36 may include the RRC parameters in an RRC message on a certain logical channel and transmit it to the terminal device 1. Here, the RRC message may be mapped to any one of the BCCH (Broadcast Control CHannel), CCCH (Common Control CHannel), and DCCH (Dedicated Control CHannel).

The radio resource control layer processing unit 36 may determine the RRC parameters to be transmitted to the terminal device 1 based on the RRC parameters included in the RRC message transmitted from the terminal device 1. Here, the RRC message transmitted from the terminal device 1 may be related to a functional information report of the terminal device 1.

The radio resource control layer processing unit 36 sets a control resource set for the terminal device 1. Multiple PDCCH candidates are configured (set) within the set control resource set. The radio resource control layer processing unit 36 sets a search space for the terminal device 1. The radio resource control layer processing unit 36 sets a DCI format to be monitored in the search space for the terminal device 1.

The radio resource control layer processing unit 36 sets the DCI format to be applied to the terminal device 1 within the control resource set. The radio resource control layer processing unit 36 generates RRC signaling indicating the DCI format to be applied to the terminal device 1. The radio resource control layer processing unit 36 sets one or more DCI formats to be applied in the transmission processing unit.

The radio resource control layer processing unit 36 performs settings related to multiple search areas. Each setting related to the multiple search areas is indexed.

The radio resource control layer processing unit 36 sets resources for transmitting HARQ-ACK to the terminal device 1. The radio resource control layer processing unit 36 sets resources for transmitting HARQ-ACK for PDSCH in the downlink frequency band (cell, component carrier, carrier). The radio resource control layer processing unit 36 sets resources for transmitting HARQ-ACK for PDSCH in the uplink frequency band (cell, component carrier, carrier).

The radio resource control layer processing unit 36 performs settings related to CSI feedback (transmission of channel state information) for the terminal device 1. The radio resource control layer processing unit 36 sets the CSI feedback transmission period, the CSI feedback transmission start timing (offset), the CSI feedback information type, and the like. The radio resource control layer processing unit 36 performs settings related to multiple CSI feedbacks. Each of the settings related to multiple CSI feedbacks is indexed.

The radio resource control layer processing unit 36 performs settings related to SPS for the terminal device 1. The radio resource control layer processing unit 36 sets the period of the SPS resources (PDSCH resources), the start timing (offset) of the SPS resources (PDSCH resources), the number of HARQ processes set for the SPS, the offset used to derive the HARQ process ID used for the SPS, the RNTI value for scheduling the SPS, and the like. The radio resource control layer processing unit 36 performs settings related to multiple SPS. The settings related to multiple SPS are each indexed.

The radio resource control layer processing unit 36 configures carrier aggregation for the terminal device 1. The radio resource control layer processing unit 36 configures a serving cell (secondary cell, primary secondary cell) as the carrier aggregation configuration. The serving cell may be configured with a downlink component carrier. The serving cell may be configured with a downlink component carrier and an uplink component carrier. The radio resource control layer processing unit 36 controls the radio transmission/reception unit 30 to perform transmission processing for the terminal device 1 using the downlink component carrier configured in the carrier aggregation configuration. The radio resource control layer processing unit 36 controls the radio transmission/reception unit 30 to perform reception processing for the terminal device 1 using the uplink component carrier configured in the carrier aggregation configuration.

The radio resource control layer processing unit 36 performs settings related to the side link for the terminal device 1. The radio resource control layer processing unit 36 sets parameters related to the side link for the terminal device 1 and notifies the terminal device 1 via the radio transceiver unit 30. For example, the following information is used as the parameters related to the side link.
- Configuring Sidelink BWP - Configuring Sidelink Radio Bearer - Configuring Sidelink Measurements

The information indicating the sidelink BWP configuration includes information indicating the starting position of the symbol in the slot used for the sidelink, the symbol length, the PSBCH configuration, the sidelink resource pool configuration, etc. The information indicating the PSBCH configuration includes information indicating parameters used for PSBCH transmission power control. The information indicating the sidelink resource pool configuration includes information indicating the sidelink receiving resource pool configuration, the sidelink transmitting resource pool configuration, etc. The sidelink transmission resource pool configuration includes the transmission resource pool configuration for the method (mode 1) in which the base station device 3 indicates scheduling information to the terminal device 1, and the transmission resource pool configuration for the method (mode 2) in which the terminal device 1 autonomously selects resources.

The information indicating the sidelink resource pool configuration includes information indicating the PSCCH configuration, information indicating the PSSCH configuration, information indicating the PSFCH configuration, information indicating the sidelink subchannel size, information indicating the start position of the sidelink subchannel, information indicating the MCS table used in the sidelink, information indicating the sidelink PTRS configuration, information indicating the sidelink TDD UL-DL configuration, information indicating the number of PRBs in the sidelink resource pool, information indicating the time resources in the sidelink resource pool, information indicating parameters of the sidelink transmit power control, information indicating the maximum number of reserved PSCCH/PSSCH resources that can be indicated in one SCI, information indicating the set of reservable resource intervals, information indicating whether the PSCCH or PSSCH DM RS is used for L1 RSRP measurement in the sensing operation, information indicating the start position of the sensing window, information indicating the end position of the sensing window, information indicating the sidelink synchronization configuration, etc.

In addition, the information indicating the configuration of the sidelink resource pool may include information indicating the slot configuration. It may include information indicating which of the following slot configurations is applied: a slot configuration in which the PSCCH can be placed only in the first half of the slot (the second OFDM symbol, or the second and third OFDM symbols), a slot configuration in which the PSCCH can be placed in the first half of the slot (the second OFDM symbol, or the second and third OFDM symbols), or a slot configuration in which the PSCCH can be placed in the second half of the slot (the ninth OFDM symbol, or the ninth and tenth OFDM symbols).

The PSSCH is arranged in the OFDM symbol following the OFDM symbol in which the PSCCH is arranged. For example, the PSSCH is arranged in the second or subsequent OFDM symbols in a slot. For example, when the PSCCH is arranged in the first half of a slot, the PSSCH is arranged in the second or subsequent OFDM symbols in the slot, and when the PSCCH is arranged in the second half of a slot, the PSSCH is arranged in the ninth or subsequent OFDM symbols in the slot.

The information indicating the configuration of the PSCCH includes information indicating the number of symbols in the PSCCH, information indicating the number of RBs that make up the PSCCH, information indicating the initial value (ID) of the scrambling of the DM RS of the PSCCH, and information indicating the number of bits reserved in the first stage SCI.

The information indicating the configuration of the PSSCH includes information indicating candidates for β offsets used to determine the number of coded modulation symbols in the 2nd stage SCI, information indicating the time domain pattern of the DM RS of the PSSCH, and information indicating a scaling factor for limiting the number of resource elements assigned to the 2nd stage SCI of the PSSCH.

The information indicating the configuration of the PSFCH includes information indicating the set of PRBs used for transmitting and receiving the PSFCH, information indicating the number of cyclic shift pairs used for transmitting the PSFCH that can be multiplexed onto one PRB, information indicating the number of PSFCH resources available for multiplexing HARQ-ACK information, information indicating the scrambling ID for sequence hopping of the PSFCH, information indicating the interval of the PSFCH resources, and information indicating the minimum time gap between the PSSCH and the PSFCH.

The information indicating the parameters of the sidelink transmission power control includes information indicating the parameters used for the transmission power control based on the sidelink path loss and information indicating the parameters used for the transmission power control based on the downlink path loss.

The information indicating the sidelink synchronization configuration includes information indicating whether the sidelink synchronization configuration is used for transmitting and receiving the sidelink synchronization signal when the terminal device 1 is synchronized to the GNSS, or whether the sidelink synchronization configuration is used for transmitting and receiving the sidelink synchronization signal when the terminal device 1 is synchronized to the base station device 3, information indicating the type of hysteresis when evaluating the synchronization reference terminal device 1, information indicating the number of sidelink SSB transmissions in one sidelink SSB section, information indicating the section and starting position of the sidelink SSB, information indicating the ID of the sidelink synchronization signal, information indicating the threshold used to determine the transmission of the sidelink synchronization signal, etc.

The information indicating the configuration of the sidelink radio bearer includes information indicating whether the terminal device 1 is the synchronization source, information indicating parameters used to detect a sidelink radio link failure, information indicating the frequency used by the sidelink, information indicating the configuration for the method (mode 1) in which the base station device 3 indicates scheduling information to the terminal device 1, information indicating the configuration for the method (mode 2) in which the terminal device 1 autonomously selects resources, information indicating whether CSI reporting is used, information indicating the configuration of the sidelink scheduling request, information indicating the priority of transmission and reception of the sidelink SSB, information indicating the RLC mode, information indicating the configuration of the sidelink logical channel, information indicating the configuration of the sidelink RLC, etc.

The information indicating the frequency at which the sidelink is used further includes information indicating the subcarrier spacing, information indicating the frequency position of the sidelink SSB, information indicating the synchronization priority, etc.

The information indicating the configuration for the method (mode 1) in which the base station device 3 instructs the terminal device 1 about scheduling information includes information indicating the RNTI used by the base station device 3 to scramble the CRC of a DCI format (e.g., DCI format 3_0) including scheduling information for the terminal device 1, information indicating the configuration of the sidelink MAC, and information indicating the configuration of the sidelink Configured Grant. The information indicating the configuration of the sidelink MAC includes information indicating the configuration of the sidelink BSR and information indicating a threshold used to determine the priority of sidelink transmission and uplink transmission. The information indicating the configuration of the Sidelink Configured Grant includes information indicating an ID for identifying the Sidelink Configured Grant, information indicating the frequency resource of the Sidelink Configured Grant, information indicating the time resource of the Sidelink Configured Grant, information indicating the HARQ process ID of the Sidelink Configured Grant, information indicating the resources used for the Sidelink HARQ-ACK transmission, information indicating the duration of the Sidelink Configured Grant, information indicating the resource pool to which the Sidelink Configured Grant is applied, information indicating the starting subchannel of the Sidelink Configured Grant, etc.

The information indicating the configuration for the method (mode 2) in which the terminal device 1 autonomously selects resources includes information indicating PSSCH transmission parameters such as MCS, subchannel number, number of retransmissions, and transmission power parameters, information indicating the probability used in resource selection, and information indicating the threshold value for RSRP used in resource selection.

The information indicating the configuration of the sidelink logical channel includes information indicating the sidelink logical channel priority, information indicating the configuration of the scheduling request applicable to the sidelink logical channel, information indicating the bit rate, information indicating the sidelink bucket size interval, information indicating whether to apply HARQ feedback to the sidelink logical channel, information indicating the subcarrier spacing applied to the resource to which the sidelink logical channel is mapped, information indicating the maximum physical channel interval of the resource to which the sidelink logical channel is mapped, information indicating the ID of the sidelink logical channel group, etc.

The information indicating the configuration of the sidelink measurement includes information indicating the frequency at which the sidelink measurement is performed, information indicating the filter coefficient applied to the sidelink measurement, information indicating the interval at which the sidelink measurement results are reported, information indicating the threshold used to decide whether to report the sidelink measurement results, information indicating the interval used to decide whether to report the sidelink measurement results, etc.

The terminal device 1 notifies the base station device 3 of information related to the sidelink by RRC signaling. The information includes information indicating the frequencies at which the terminal device 1 is interested in receiving sidelink communications, information indicating the frequencies at which the terminal device 1 is interested in transmitting sidelink communications, information indicating parameters for requesting sidelink transmission resources, information about sidelink capabilities, information indicating the cast type (broadcast, groupcast, unicast) for which sidelink resources are requested, information indicating the destination identity, information about sidelink QoS, information indicating the RLC mode, and information indicating a list of synchronization references used by the terminal device 1.

The medium access control layer processing unit (MAC layer processing unit) 35 generates MAC CE (SCell Activation/Deactivation MAC CEs) that instructs activation/deactivation of a secondary cell. The medium access control layer processing unit (MAC layer processing unit) 35 generates MAC CE that instructs activation/deactivation of a secondary cell for a plurality of serving cells configured by the radio resource control layer processing unit 36. The medium access control layer processing unit (MAC layer processing unit) 35 deactivates a secondary cell based on a timer. The medium access control layer processing unit (MAC layer processing unit) 35 determines that scheduling is not performed for a certain period of time for a serving cell by measuring with a timer, deactivates the serving cell, and controls the radio transmission/reception unit 30.

The functions of the wireless transceiver unit 30 are similar to those of the wireless transceiver unit 10, and therefore a description thereof will be omitted where appropriate. The wireless transceiver unit 30 performs physical layer processing. Here, the physical layer processing may include some or all of the following: generation of a baseband signal for a physical channel, generation of a baseband signal for a physical signal, detection of information transmitted by the physical channel, and detection of information transmitted by the physical signal. Furthermore, the physical layer processing may include a mapping process of a transport channel to a physical channel. Here, the baseband signal is also referred to as a time-continuous signal.

The wireless transceiver 30 may perform one or both of demodulation and decoding processes. The wireless transceiver 30 may deliver a transport block of the information detected based on the demodulation and decoding processes of the received physical signal to a higher layer on the UL-SCH. For example, the wireless transceiver 30 may generate a baseband signal of a downlink physical channel. Here, the transport block delivered from a higher layer on the DL-SCH may be placed in the downlink physical channel. For example, the wireless transceiver 30 may generate a baseband signal of a downlink physical signal.

The wireless transceiver 30 may perform some or all of the modulation process, the encoding process, and the transmission process. The wireless transceiver 30 may generate a physical signal based on some or all of the encoding process, the modulation process, and the baseband signal generation process for the transport block. The wireless transceiver 30 may place the physical signal in a certain BWP. The wireless transceiver 30 may transmit the generated physical signal. For example, the wireless transceiver 30 may attempt to detect information transmitted by an uplink physical channel. Here, the transport block of the information transmitted by the uplink physical channel may be delivered to a higher layer on the UL-SCH. For example, the wireless transceiver 30 may attempt to detect information transmitted by an uplink physical signal.

The wireless transmission/reception unit 30 grasps the SS (Search space) configured in the terminal device 1. The wireless transmission/reception unit 30 grasps the search space in the control resource set configured in the terminal device 1. The wireless transmission/reception unit 30 grasps the PDCCH candidates monitored in the terminal device 1 to grasp the search space. The wireless transmission/reception unit 30 grasps which control channel element each PDCCH candidate monitored in the terminal device 1 is composed of (grabs the number of the control channel element in which the PDCCH candidate is composed). The wireless transmission/reception unit 30 includes an SS grasping unit, which grasps the SS configured in the terminal device 1. The SS grasping unit grasps one or more PDCCH candidates in the control resource set configured as the search space of the terminal device. The SS grasping unit grasps the PDCCH candidates (the number of PDCCH candidates, the number of the PDCCH candidate) configured in the search space of the control resource set of the terminal device 1.

The SS grasping unit grasps the configuration of the search area within the control resource set (the number of PDCCH candidates, the OFDM symbols of the PDCCH candidates, and the aggregation level of the PDCCH candidates). The transmitting unit (transmission processing unit) of the wireless transceiver unit 30 transmits a PDCCH to the terminal device 1 using the PDCCH candidates within the search area of the control resource set.

A transmitter (also referred to as a transmission processing unit) of the base station device 3 transmits the PDCCH. The transmission processing unit of the base station device 3 transmits the PDCCH using PDCCH candidates monitored in the terminal device 1. The transmission processing unit of the base station device 3 transmits the PDCCH using resources corresponding to PDCCH candidates in a search space set for the terminal device 1. The transmission processing unit of the base station device 3 transmits the PDCCH using PDCCH candidates in a search space where the PDCCH is monitored in the terminal device 1, among a plurality of search spaces set for the terminal device 1.

The receiving unit (also referred to as the receiving processing unit) of base station device 3 receives the HARQ-ACK. The receiving processing unit of base station device 3 receives the HARQ-ACK for the PDSCH. The receiving processing unit of base station device 3 receives the HARQ-ACK in the uplink frequency band (cell, component carrier, carrier). The receiving processing unit of base station device 3 receives the HARQ-ACK for the PDSCH in the downlink frequency band (cell, component carrier, carrier) managed by base station device 3.

The receiving section of the base station device 3 receives the sidelink HARQ-ACK from the terminal device 1. The terminal device 1 transmits the sidelink HARQ-ACK information acquired from the PSFCH received from the communication destination terminal device 1 via the sidelink to the base station device 3 using the PUCCH.

The wireless transceiver unit 30 stops various reception processes and various transmission processes in the deactivated serving cell. For example, the wireless transceiver unit 30 stops transmitting the PDCCH in the deactivated serving cell. For example, the wireless transceiver unit 30 stops transmitting the PDSCH in the deactivated serving cell. For example, the wireless transceiver unit 30 stops receiving the SRS in the deactivated serving cell. For example, the wireless transceiver unit 30 stops receiving the PUSCH in the deactivated serving cell.

The RF unit 32 may convert the signal received via the antenna unit 31 into a baseband signal and remove unnecessary frequency components. The RF unit 32 outputs the baseband signal to the baseband unit 33.

The baseband unit 33 may digitize the baseband signal input from the RF unit 32. The baseband unit 33 may remove a portion corresponding to a cyclic prefix (CP) from the digitized baseband signal. The baseband unit 33 may perform a fast Fourier transform (FFT) on the baseband signal from which the CP has been removed, and extract a signal in the frequency domain.

The baseband unit 33 may generate a baseband signal by performing an inverse fast Fourier transform (IFFT) on the physical signal. The baseband unit 33 may add a CP to the generated baseband signal. The baseband unit 33 may convert the baseband signal to which the CP has been added into an analog signal. The baseband unit 33 may output the analogized baseband signal to the RF unit 32.

The RF unit 32 may remove unnecessary frequency components from the baseband signal input from the baseband unit 33. The RF unit 32 may up-convert the baseband signal to a carrier frequency to generate an RF signal. The RF unit 32 may transmit the RF signal via the antenna unit 31. The RF unit 32 may also have a function of controlling the transmission power.

Each of the units numbered 10 to 16 in the terminal device 1 may be configured as a circuit. Each of the units numbered 30 to 36 in the base station device 3 may be configured as a circuit.

The following describes the physical channels and physical signals related to various aspects of this embodiment.

Physical signal is a general term for the downlink physical channel, downlink physical signal, uplink physical channel, and uplink physical channel. Physical channel is a general term for the downlink physical channel and uplink physical channel. Physical signal is a general term for the downlink physical signal and uplink physical signal.

The uplink physical channel may correspond to a set of resource elements carrying information generated in a higher layer. The uplink physical channel is a physical channel used in an uplink component carrier. The uplink physical channel may be transmitted by the radio transceiver unit 10. The uplink physical channel may be received by the radio transceiver unit 30. In a wireless communication system according to one aspect of the present embodiment, at least some or all of the following uplink physical channels are used.
・PUCCH (Physical Uplink Control CHannel)
・PUSCH (Physical Uplink Shared CHannel)
・PRACH (Physical Random Access CHannel)

The PUCCH may be used to transmit (transmit) uplink control information (UCI). The uplink control information may be placed in the PUCCH. The radio transceiver unit 10 may transmit the PUCCH in which the uplink control information is placed. The radio transceiver unit 30 may receive the PUCCH in which the uplink control information is placed.

The uplink control information (uplink control information bit, uplink control information sequence, uplink control information type) includes some or all of the channel state information (CSI: Channel State Information), scheduling request (SR: Scheduling Request), and HARQ-ACK (Hybrid Automatic Repeat request ACKnowledgement) information. Note that the uplink control information may also include information not described above.

The channel state information is also called channel state information bits or channel state information sequences. The scheduling request is also called scheduling request bits or scheduling request sequences. The HARQ-ACK information is also called HARQ-ACK information bits or HARQ-ACK information sequences.

The HARQ-ACK information may consist of HARQ-ACK bits corresponding to one transport block (TB). The HARQ-ACK bits may indicate an acknowledgement (ACK) or a negative-acknowledgement (NACK) corresponding to the transport block. The ACK may indicate that the decoding of the transport block has been successfully completed. The NACK may indicate that the decoding of the transport block has not been successfully completed. The HARQ-ACK information may include one or more HARQ-ACK bits.

HARQ-ACK for a transport block is also referred to as HARQ-ACK for a PDSCH. Here, "HARQ-ACK for a PDSCH" may refer to a HARQ-ACK for a transport block included in the PDSCH.

The scheduling request may be used to request UL-SCH resources for the initial transmission. The scheduling request bit may be used to indicate either a positive SR or a negative SR. When the scheduling request bit indicates a positive SR, this is also referred to as "a positive SR is transmitted (communicated)". A positive SR may indicate that UL-SCH resources for the initial transmission are requested by the terminal device 1. When the scheduling request bit indicates a negative SR, this is also referred to as "a negative SR is transmitted (communicated)". A negative SR may indicate that UL-SCH resources for the initial transmission are not requested by the terminal device 1.

The channel state information may include some or all of a Channel Quality Indicator (CQI), a Precoder Matrix Indicator (PMI), and a Rank Indicator (RI). CQI is an indicator related to the quality of the propagation path (e.g., propagation strength) or the quality of the physical channel, and PMI is an indicator related to the precoder. RI is an indicator related to the transmission rank (or the number of transmission layers).

The channel state information is an indicator regarding the reception state of a physical signal (e.g., CSI-RS) used for channel measurement. The value of the channel state information may be determined by the terminal device 1 based on the reception state assumed by the physical signal used for channel measurement. The channel measurement may include interference measurement.

The PUCCH may be accompanied by a PUCCH format. Here, the PUCCH format may be the format of the physical layer processing of the PUCCH. The PUCCH format may also be the format of the information transmitted using the PUCCH.

The PUSCH may be transmitted to transmit uplink control information and/or a transport block. The PUSCH may be used to transmit uplink control information and/or a transport block. The PUSCH may be used to transmit at least some or all of the transport block, HARQ-ACK, channel state information, and scheduling request. The PUSCH is used at least to transmit the random access message 3. The PUSCH may be used to transmit information not described above. The terminal device 1 may transmit a PUSCH in which the uplink control information and/or a transport block is arranged. The base station device 3 may receive a PUSCH in which the uplink control information and/or a transport block is arranged.

The PRACH may be transmitted to convey the index of the random access preamble (random access message 1). The terminal device 1 may transmit the PRACH. The base station device 3 may receive the PRACH. The terminal device 1 may transmit the random access preamble on the PRACH. The base station device 3 may receive the random access preamble on the PRACH.

The uplink physical signal may correspond to a set of resource elements. The uplink physical signal may not be used to transmit information generated in a higher layer. In addition, the uplink physical signal may be used to transmit information generated in a physical layer. The uplink physical signal may be a physical signal used in an uplink component carrier. The radio transceiver unit 10 may transmit the uplink physical signal. The radio transceiver unit 30 may receive the uplink physical signal. In the uplink of the wireless communication system according to one aspect of the present embodiment, some or all of the following uplink physical signals may be used.
・UL DMRS (UpLink Demodulation Reference Signal)
・SRS (Sounding Reference Signal)
・UL PTRS (UpLink Phase Tracking Reference Signal)

UL DMRS is a general term for DMRS for PUSCH and DMRS for PUCCH.

The set of antenna ports for the DMRS for the PUSCH (DMRS related to the PUSCH, DMRS included in the PUSCH, DMRS corresponding to the PUSCH) may be given based on the set of antenna ports for the PUSCH. For example, the set of antenna ports for the DMRS for the PUSCH may be the same as the set of antenna ports for the PUSCH.

The propagation path of the PUSCH may be estimated from the DMRS for that PUSCH.

The set of antenna ports for DMRS for PUCCH (DMRS related to PUCCH, DMRS included in PUCCH, DMRS corresponding to PUCCH) may be the same as the set of antenna ports for PUCCH.

The propagation path of the PUCCH may be estimated from the DMRS for that PUCCH.

The downlink physical channel may correspond to a set of resource elements that convey information generated in a higher layer. The downlink physical channel may be a physical channel used in a downlink component carrier. The radio transceiver unit 30 may transmit the downlink physical channel. The radio transceiver unit 10 may receive the downlink physical channel. In the downlink of the wireless communication system according to one aspect of the present embodiment, some or all of the following downlink physical channels may be used.
・PBCH (Physical Broadcast Channel)
・PDCCH (Physical Downlink Control Channel)
・PDSCH (Physical Downlink Shared Channel)

The PBCH is transmitted to convey the Master Information Block (MIB) and/or physical layer control information. Here, the physical layer control information is information generated in the physical layer. The MIB is an RRC message delivered from higher layers on the BCCH (Broadcast Control CHannel).

The PDCCH is used at least for transmitting (transmitting) downlink control information (DCI). The downlink control information may be placed in the PDCCH. The terminal device 1 may receive the PDCCH in which the downlink control information is placed. The base station device 3 may transmit the PDCCH in which the downlink control information is placed.

The downlink control information may be transmitted with a DCI format. The DCI format may be interpreted as a format of the downlink control information. The DCI format may also be interpreted as a set of downlink control information set to a certain downlink control information format.

The base station device 3 may notify the terminal device 1 of the downlink control information using a PDCCH with a DCI format. Here, the terminal device 1 may monitor the PDCCH to acquire the downlink control information. Unless otherwise specified, the DCI format and the downlink control information may be described as equivalent. For example, the base station device 3 may include the downlink control information in the DCI format and transmit it to the terminal device 1. Furthermore, the terminal device 1 may control the radio transceiver unit 10 using the downlink control information included in the detected DCI format.

The downlink control information may include at least one of a downlink grant (DL grant) or an uplink grant (UL grant). The DCI format used for scheduling the PDSCH is also referred to as the downlink DCI format. The DCI format used for scheduling the PUSCH is also referred to as the uplink DCI format. The downlink grant is also referred to as a downlink assignment (DL assignment) or a downlink allocation (DL allocation).

DCI format 0_0, DCI format 0_1, DCI format 1_0, and DCI format 1_1 are DCI formats. The uplink DCI format is a general term for DCI format 0_0 and DCI format 0_1. The downlink DCI format is a general term for DCI format 1_0 and DCI format 1_1.

DCI format 0_0 is used for scheduling a PUSCH allocated to a certain cell. DCI format 0_0 includes at least some or all of DCI formats 1A to 1E.
1A) Identifier for DCI formats field
1B) Frequency domain resource assignment field
1C) Time domain resource assignment field
1D) Frequency hopping flag field
1E) MCS field (Modulation and Coding Scheme field)

The DCI format specification field may indicate whether the DCI format including the DCI format specification field is an uplink DCI format or a downlink DCI format. In other words, the DCI format specification field may be included in both the uplink DCI format and the downlink DCI format. Here, the DCI format specification field included in DCI format 0_0 may indicate 0.

The frequency domain resource allocation field included in DCI format 0_0 may be used to indicate the allocation of frequency resources for the PUSCH scheduled by DCI format 0_0.

The time domain resource allocation field included in DCI format 0_0 may be used to indicate the allocation of time resources for the PUSCH scheduled by DCI format 0_0.

The frequency hopping flag field may be used to indicate whether frequency hopping is applied to the PUSCH scheduled by the DCI format 0_0.

The MCS field included in DCI format 0_0 may be used to indicate one or both of the modulation scheme for the PUSCH scheduled by DCI format 0_0 and the target coding rate scheduled by DCI format 0_1.
The target coding rate may be a target coding rate for a transport block arranged in the PUSCH. A size of a transport block (TBS) arranged in the PUSCH may be determined based on the target coding rate and a part or all of a modulation scheme for the PUSCH.

DCI format 0_0 may not include fields used in CSI requests. DCI format 0_0 may not include a carrier indicator field. DCI format 0_0 may not include a BWP field.

DCI format 0_1 is used for scheduling a PUSCH allocated to a certain cell. DCI format 0_1 includes some or all of fields 2A to 2H.
2A) DCI Format Specific Fields
2B) Frequency domain resource allocation field
2C) Time domain resource allocation field
2D) Frequency hopping flag field
2E) MCS Field
2F) CSI request field
2G) BWP field
2H) UL DAI field (downlink assignment index)

The DCI format specific field included in DCI format 0_1 may indicate 0.

The frequency domain resource allocation field included in DCI format 0_1 may be used to indicate the allocation of frequency resources for the PUSCH scheduled by the DCI format 0_1.

The time domain resource allocation field included in DCI format 0_1 may be used to indicate the allocation of time resources for the PUSCH scheduled by the DCI format 0_1.

The MCS field included in DCI format 0_1 may be used to indicate one or both of the modulation scheme for the PUSCH scheduled by the DCI format 0_1 and the target coding rate for the PUSCH scheduled by the DCI format 0_1.

The CSI request field may be used to indicate the reporting of CSI.

The BWP field of DCI format 0_1 may be used to indicate the uplink BWP in which the PUSCH scheduled by the DCI format 0_1 is placed. In other words, DCI format 0_1 may or may not involve a change in the active uplink BWP. The terminal device 1 may recognize the uplink BWP in which the PUSCH is placed based on detecting DCI format 0_1 used for scheduling the PUSCH.

If DCI format 0_1 includes a carrier indicator field, the carrier indicator field may be used to indicate the serving cell of the uplink component carrier in which the PUSCH is placed. Based on detecting DCI format 0_1 in the downlink component carrier of a serving cell, the terminal device 1 may recognize that the PUSCH scheduled by the DCI format 0_1 is placed in the uplink component carrier of the serving cell indicated by the carrier indicator field included in the DCI format 0_1.

If DCI format 0_1 does not include a carrier indicator field, the serving cell to which the uplink component carrier on which the PUSCH scheduled by DCI format 0_1 is placed may be the same as the serving cell of the downlink component carrier on which the PDCCH including the DCI format 0_1 is placed. Based on detecting DCI format 0_1 in a downlink component carrier of a serving cell, the terminal device 1 may recognize that the PUSCH scheduled by DCI format 0_1 is to be placed on the uplink component carrier of the serving cell.

The UL DAI field is at least used to indicate the transmission status of the PDSCH. If a dynamic HARQ-ACK codebook is used, the size of the UL DAI field may be 2 bits. The UL DAI field indicates the size of the HARQ-ACK codebook transmitted on the PUSCH. The UL DAI field indicates the number of HARQ-ACKs included in the HARQ-ACK codebook transmitted on the PUSCH. The UL DAI field indicates the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH. The UL DAI field indicates the number of PDSCHs and SPS releases in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH.

The UL DAI field may indicate a value to which a modulo operation has been applied. An example will be described in which the UL DAI field is 2 bits. If the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH is 0, the UL DAI field indicates "00". If the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH is 1, the UL DAI field indicates "01". If the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH is 2, the UL DAI field indicates "10". If the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted on the PUSCH is 3, the UL DAI field indicates "11". If the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted by the PUSCH is four, the UL DAI field indicates "00". If the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted by the PUSCH is five, the UL DAI field indicates "01". If the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted by the PUSCH is six, the UL DAI field indicates "10". If the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted by the PUSCH is seven, the UL DAI field indicates "11". In this example, a modulo operation is performed using the number '4' on the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted by the PUSCH.

The terminal device 1 interprets the UL DAI field taking into consideration the total number of received PDSCHs. For example, the terminal device 1 receives four PDSCHs and receives a UL DAI field indicating "00". In this case, the terminal device 1 interprets that the number of PDSCHs in which the corresponding HARQ-ACK is included in the HARQ-ACK codebook transmitted by the PUSCH, which is indicated by the UL DAI field, is four.
For example, the terminal device 1 receives three PDSCHs and receives a UL DAI field indicating "00." In this case, the terminal device 1 interprets that the number of PDSCHs including the corresponding HARQ-ACK in the HARQ-ACK codebook transmitted by the PUSCH, which is indicated by the UL DAI field, is four, and determines that reception of one PDSCH has been missed.

DCI format 1_0 is used for scheduling a PDSCH allocated to a certain cell. DCI format 1_0 includes some or all of 3A to 3F.
3A) DCI Format Specific Fields
3B) Frequency domain resource allocation field
3C) Time domain resource allocation field
3D) MCS field
3E) PDSCH to HARQ feedback timing indicator field
3F) PUCCH resource indicator field

The DCI format specific field included in DCI format 1_0 may indicate 1.

The frequency domain resource allocation field included in DCI format 1_0 may be used to indicate the allocation of frequency resources for the PDSCH scheduled by that DCI format.

The time domain resource allocation field included in DCI format 1_0 may be used to indicate the allocation of time resources for the PDSCH scheduled by that DCI format.

The MCS field included in DCI format 1_0 may be used to indicate one or both of a modulation scheme for a PDSCH scheduled by the DCI format and a target coding rate for a PDSCH scheduled by the DCI format. The target coding rate may be a target coding rate for a transport block arranged in the PDSCH. The size of the transport block (TBS) arranged in the PDSCH may be determined based on one or both of the target coding rate and the modulation scheme for the PDSCH.

The PDSCH_HARQ feedback timing indication field may be used to indicate an offset from the slot containing the last OFDM symbol of the PDSCH to the slot containing the first OFDM symbol of the PUCCH. The timing indication field from the PDSCH to the HARQ feedback may be a field indicating timing K1. If the index of the slot containing the last OFDM symbol of the PDSCH is slot n, the index of the slot containing a PUCCH or a PUSCH containing at least a HARQ-ACK corresponding to a transport block contained in the PDSCH may be n+K1. If the index of the slot containing the last OFDM symbol of the PDSCH is slot n, the index of the slot containing the first OFDM symbol of the PUCCH or the first OFDM symbol of the PUSCH containing at least a HARQ-ACK corresponding to a transport block contained in the PDSCH may be n+K1.

The PDSCH_HARQ feedback timing indication field may be referred to as the PDSCH-to-HARQ feedback timing indicator field or the HARQ indication field.

The PUCCH resource indication field may be used to indicate the PUCCH resource.

DCI format 1_1 is used for scheduling a PDSCH arranged in a certain cell. DCI format 1_1 includes some or all of 4A to 4I.
4A) DCI Format Specific Fields
4B) Frequency domain resource allocation field
4C) Time domain resource allocation field
4E) MCS Field
4F) PDSCH_HARQ feedback timing indication field
4G) PUCCH resource indication field
4H) BWP Field
4I) Career Indicator Field

The DCI format specific field contained in DCI format 1_1 may indicate 1.

The frequency domain resource allocation field included in DCI format 1_1 may be used to indicate the allocation of frequency resources for the PDSCH scheduled by DCI format 1_1.

The time domain resource allocation field included in DCI format 1_1 may be used to indicate the allocation of time resources for the PDSCH scheduled by DCI format 1_1.

The MCS field included in DCI format 1_1 may be used to indicate one or both of the modulation scheme for the PDSCH scheduled by DCI format 1_1 and the target coding rate for the PDSCH scheduled by DCI format 1_1.

If DCI format 1_1 includes a PDSCH_HARQ feedback timing indication field, the PDSCH_HARQ feedback timing indication field may be used to indicate an offset from the slot containing the last OFDM symbol of the PDSCH to the slot containing the first OFDM symbol of the PUCCH. If DCI format 1_1 does not include a PDSCH_HARQ feedback timing indication field, a parameter indicating the offset from the slot containing the last OFDM symbol of the PDSCH to the slot containing the first OFDM symbol of the PUCCH may be provided by the RRC layer.

The PUCCH resource indication field may be used to indicate the PUCCH resource.

The BWP field of DCI format 1_1 may be used to indicate the downlink BWP in which the PDSCH scheduled by the DCI format 1_1 is placed. In other words, DCI format 1_1 may or may not involve a change in the active downlink BWP. The terminal device 1 may recognize the downlink BWP in which the PDSCH is placed based on detecting DCI format 1_1 used for scheduling the PDSCH.

The DCI format 1_1 that does not include a BWP field may be a DCI format that schedules a PDSCH without changing the active downlink BWP. The terminal device 1 may recognize that it will receive the PDSCH without switching the active downlink BWP based on detecting the DCI format 1_1 that is used for scheduling a PDSCH and does not include a BWP field.

When a carrier indicator field is included in DCI format 1_1, the carrier indicator field may be used to indicate a serving cell of a downlink component carrier on which a PDSCH scheduled by the DCI format 1_1 is arranged. Based on detecting DCI format 1_1 in a downlink component carrier of a serving cell, the terminal device 1 may recognize that a PDSCH scheduled by the DCI format 1_1 is arranged on a downlink component carrier of a serving cell indicated by the carrier indicator field included in the DCI format 1_1.

If DCI format 1_1 does not include a carrier indicator field, the downlink component carrier on which the PDSCH scheduled by DCI format 1_1 is arranged may be the same as the downlink component carrier on which the PDCCH including the DCI format 1_1 is arranged. The terminal device 1 may recognize that the PDSCH scheduled by the DCI format 1_1 is arranged on a downlink component carrier based on detecting DCI format 1_1 in the downlink component carrier.

The downlink grant is used at least for scheduling one PDSCH in one serving cell. The downlink grant is used at least for scheduling a PDSCH in the same slot in which the downlink grant is transmitted. The downlink grant may be used for scheduling a PDSCH in a slot different from the slot in which the downlink grant is transmitted. The uplink grant is used at least for scheduling one PUSCH in one serving cell.

In addition, various DCI formats may further include fields different from the above-mentioned fields. A field indicating the cumulative number of PDCCHs transmitted (C-DAI: Counter Downlink Assignment Index field) may be included. A field indicating the total number of PDCCHs transmitted (T-DAI: Total Downlink Assignment Index field) may be included.

The PDSCH may be transmitted to transmit a transport block. The PDSCH may be used to transmit a transport block. The transport block may be placed in the PDSCH. The base station device 3 may transmit the PDSCH in which the transport block is placed. The terminal device 1 may receive the PDSCH in which the transport block is placed.

The downlink physical signal may correspond to a set of resource elements. The downlink physical signal may not be used to transmit information generated in a higher layer. The downlink physical signal may be used to transmit information generated in a physical layer. The downlink physical signal may be a physical signal used in a downlink component carrier. The radio transceiver unit 10 may receive the downlink physical signal. The radio transceiver unit 30 may transmit the downlink physical signal. In the downlink of the wireless communication system according to one aspect of the present embodiment, at least some or all of the following downlink physical signals may be used.
・Synchronization signal (SS)
・DL DMRS (DownLink DeModulation Reference Signal)
・CSI-RS (Channel State Information-Reference Signal)
・DL PTRS (DownLink Phase Tracking Reference Signal)

The synchronization signal is used by the terminal device 1 to synchronize the frequency domain and/or time domain of the downlink. The synchronization signal is a general term for the PSS (Primary Synchronization Signal) and the SSS (Secondary Synchronization Signal).

An SS block (SS/PBCH block) is composed of at least the PSS, SSS, and some or all of the PBCH.

The antenna ports for PSS, SSS, PBCH, and DMRS for PBCH may be the same.

The PBCH on which the PBCH symbol is transmitted at a certain antenna port is a DMRS for the PBCH that is placed in the slot to which the PBCH is mapped, and may be estimated by the DMRS for the PBCH included in the SS/PBCH block to which the PBCH belongs.

DL DMRS is a general term for DMRS for PBCH, DMRS for PDSCH, and DMRS for PDCCH.

The set of antenna ports for a DMRS for a PDSCH (DMRS related to a PDSCH, DMRS included in a PDSCH, DMRS corresponding to a PDSCH) may be given based on the set of antenna ports for the PDSCH. For example, the set of antenna ports for a DMRS for a PDSCH may be the same as the set of antenna ports for the PDSCH.

The propagation path of a PDSCH may be estimated from the DMRS for the PDSCH. If a set of resource elements through which a PDSCH symbol is transmitted and a set of resource elements through which a DMRS symbol for the PDSCH is transmitted are included in the same precoding resource group (PRG), the PDSCH through which the PDSCH symbol is transmitted at an antenna port may be estimated by the DMRS for the PDSCH.

The antenna port for DMRS for PDCCH (DMRS related to PDCCH, DMRS included in PDCCH, DMRS corresponding to PDCCH) may be the same as the antenna port for PDCCH.

The propagation path of a PDCCH may be estimated from the DMRS for that PDCCH. If the same precoder is applied (assumed to be applied, assumed to be applied) to a set of resource elements on which a PDCCH symbol is transmitted and a set of resource elements on which a DMRS symbol for that PDCCH is transmitted, the PDCCH on which a PDCCH symbol is transmitted at an antenna port may be estimated by the DMRS for that PDCCH.

BCH (Broadcast CHannel), UL-SCH (Uplink-Shared CHannel), and DL-SCH (Downlink-Shared CHannel) are transport channels.

The BCH of the transport layer may be mapped to the PBCH of the physical layer. That is, the transport block delivered from a higher layer on the BCH of the transport layer may be placed on the PBCH of the physical layer. Also, the UL-SCH of the transport layer may be mapped to the PUSCH of the physical layer.

The transport layer may apply Hybrid Automatic Repeat reQuest (HARQ) to the transport block.

The BCCH (Broadcast Control CHannel), the CCCH (Common Control CHannel), and the DCCH (Dedicated Control CHannel) are logical channels. For example, the BCCH may be used to deliver an RRC message including an MIB or an RRC message including system information. The CCCH may be used to transmit an RRC message including an RRC parameter common to a plurality of terminal devices 1. Here, the CCCH may be used, for example, for a terminal device 1 that is not RRC-connected. The DCCH may be used to transmit an RRC message dedicated to a certain terminal device 1. Here, the DCCH may be used, for example, for a terminal device 1 that is RRC-connected.

The BCCH may be mapped to the BCH or DL-SCH. In other words, an RRC message containing MIB information may be delivered to the BCH. An RRC message containing system information other than MIB may be delivered to the DL-SCH. The CCCH may be mapped to the DL-SCH or UL-SCH. In other words, an RRC message mapped to the CCCH may be delivered to the DL-SCH or UL-SCH. The DCCH may be mapped to the DL-SCH or UL-SCH. In other words, an RRC message mapped to the DCCH may be delivered to the DL-SCH or UL-SCH.

UL-SCH may be mapped to PUSCH. DL-SCH may be mapped to PDSCH. BCH may be mapped to PBCH.

The media access control layer processing unit 15 may implement a random access procedure.

For example, downlink control information including a downlink grant or an uplink grant is transmitted and received on the PDCCH, including the C-RNTI (Cell-Radio Network Temporary Identifier).

A physical channel may be mapped to a serving cell. A physical channel may be mapped to a BWP that is configured on a carrier included in the serving cell.

The terminal device 1 may be configured with one or more control resource sets (CORESET: Control Resource SET). The terminal device 1 monitors the PDCCH in one or more control resource sets. Here, monitoring the PDCCH in one or more control resource sets may include monitoring one or more PDCCHs corresponding to each of the one or more control resource sets. Note that the PDCCH may include one or more PDCCH candidates and/or a set of PDCCH candidates. Furthermore, monitoring the PDCCH may include monitoring and detecting the PDCCH and/or a DCI format transmitted via the PDCCH.

Multiple control resource sets may be configured in the terminal device 1, and each control resource set may be assigned an index (control resource set index). One or more control channel elements (CCEs) may be configured within the control resource set, and each CCE may be assigned an index (CCE index).

The set of PDCCH candidates monitored by terminal device 1 is defined in terms of a search space. In other words, the set of PDCCH candidates monitored by terminal device 1 is given by the search space.

The search space may be configured to include one or more PDCCH candidates of one or more aggregation levels. The aggregation level of a PDCCH candidate may indicate the number of CCEs that make up the PDCCH. A PDDCH candidate may be mapped to one or more CCEs.

The search area set may be configured to include at least one or more search areas. Each search area may be assigned an index (search area index).

Each of the search area sets may be associated with at least one control resource set. Each of the search area sets may be included in one control resource set. For each of the search area sets, an index of the control resource set associated with the search area set may be given.

The terminal device 1 can detect the PDCCH and/or DCI for the terminal device 1 by blindly searching the PDCCH candidates included in the search area within the control resource set.

In various aspects of this embodiment, unless otherwise specified, the number of resource blocks refers to the number of resource blocks in the frequency domain.

The terminal device 1 transmits uplink control information (UCI) to the base station device 3. The terminal device 1 may multiplex the UCI onto a PUCCH and transmit it. The terminal device 1 may multiplex the UCI onto a PUSCH and transmit it. The UCI may include at least one of downlink channel state information (Channel State Information: CSI), a scheduling request (Scheduling Request: SR) indicating a request for PUSCH resources, and a Hybrid Automatic Repeat request ACKnowledgement (HARQ-ACK) for downlink data (Transport block, Medium Access Control Protocol Data Unit: MAC PDU, Downlink-Shared Channel: DL-SCH, Physical Downlink Shared Channel: PDSCH).

HARQ-ACK may also be referred to as ACK/NACK, HARQ feedback, HARQ-ACK feedback, HARQ response, HARQ-ACK response, HARQ information, HARQ-ACK information, HARQ control information, and HARQ-ACK control information.

If the data is successfully decoded, an ACK is generated for the data. If the data is not successfully decoded, a NACK is generated for the data. The HARQ-ACK may include at least a HARQ-ACK bit corresponding to at least one transport block. The HARQ-ACK bit may indicate an ACK (ACKnowledgement) or a NACK (Negative-ACKnowledgement) corresponding to one or more transport blocks. The HARQ-ACK may include at least a HARQ-ACK codebook including one or more HARQ-ACK bits. The HARQ-ACK bit corresponding to one or more transport blocks may correspond to a PDSCH including the one or more transport blocks.

HARQ control for one transport block may be referred to as an HARQ process. One HARQ process identifier may be given for each HARQ process. The DCI format includes a field indicating the HARQ process identifier (HARQ process number).

An NDI (New Data Indicator) is indicated in the DCI format for each HARQ process. For example, an NDI field is included in a DCI format (DL assignment) that includes scheduling information for PDSCH. The NDI field is 1 bit. The terminal device 1 stores (stores) an NDI value for each HARQ process. The base station device 3 stores (stores) an NDI value for each HARQ process for each terminal device 1. The terminal device 1 updates the stored NDI value using the NDI field of the detected DCI format. The base station device 3 sets the updated NDI value or the non-updated NDI value in the NDI field of the DCI format and transmits it to the terminal device 1. The terminal device 1 updates the stored NDI value using the NDI field of the detected DCI format for the HARQ process corresponding to the value of the HARQ process identifier field of the detected DCI format.

The terminal device 1 determines whether the received transport block is a new transmission or a retransmission based on the value of the NDI field of the DCI format (DL assignment). The terminal device 1 compares the value of the NDI field of the detected DCI format with the value of the NDI previously received for the transport block of a certain HARQ process, and if the value is toggled, determines that the received transport block is a new transmission. When the base station device 3 transmits a transport block of a new transmission in a certain HARQ process, it toggles the value of the NDI stored for the HARQ process and transmits the toggled NDI to the terminal device 1. When the base station device 3 transmits a transport block of a retransmission in a certain HARQ process, it does not toggle the value of the NDI stored for the HARQ process, and transmits the untoggled NDI to the terminal device 1. The terminal device 1 compares the value of the NDI field of the detected DCI format with the value of the NDI previously received for the transport block of a certain HARQ process, and if the value is not toggled (they are the same), determines that the received transport block is a retransmission. Note that toggling here means switching between different values.

The terminal device 1 may report HARQ-ACK information to the base station device 3 using a HARQ-ACK codebook in a slot indicated by the value of the HARQ indication field included in DCI format 1_0 corresponding to PDSCH reception or DCI format 1_1.

For DCI format 1_0, the value of the HARQ indication field may be mapped to a set of slot numbers (1, 2, 3, 4, 5, 6, 7, 8). For DCI format 1_1, the value of the HARQ indication field may be mapped to a set of slot numbers given by the higher layer parameter dl-DataToUL-ACK. The number of slots indicated based at least on the value of the HARQ indication field may also be referred to as HARQ-ACK timing or K1. For example, a HARQ-ACK indicating the decoding status of the PDSCH (downlink data) transmitted in slot n may be reported (transmitted) in slot n+K1.

dl-DataToUL-ACK indicates a list of timings of HARQ-ACK for PDSCH. The timing is the number of slots between the slot in which PDSCH is received (or the slot containing the last OFDM symbol to which PDSCH is mapped) and the slot in which HARQ-ACK for the received PDSCH is transmitted. For example, dl-DataToUL-ACK is a list of 1, 2, 3, 4, 5, 6, 7, or 8 timings. If dl-DataToUL-ACK is a list of 1 timing, the HARQ indication field is 0 bits. If dl-DataToUL-ACK is a list of 2 timings, the HARQ indication field is 1 bit. If dl-DataToUL-ACK is a list of 3 or 4 timings, the HARQ indication field is 2 bits. If dl-DataToUL-ACK is a list of 5, 6, 7, or 8 timings, the HARQ indication field is 3 bits. For example, the dl-DataToUL-ACK is composed of a list of timings whose values range from 0 to 31. For example, the dl-DataToUL-ACK is composed of a list of timings whose values range from 0 to 63.

The size of the dl-DataToUL-ACK is defined as the number of elements it contains. The size of the dl-DataToUL-ACK may be referred to as Lpara. The index of the dl-DataToUL-ACK indicates the order (number) of the elements of the dl-DataToUL-ACK. For example, if the size of the dl-DataToUL-ACK is 8 (Lpara = 8), the index of the dl-DataToUL-ACK is one of the values 1, 2, 3, 4, 5, 6, 7, or 8. The index of the dl-DataToUL-ACK may be given, indicated, or indicated by the value indicated by the HARQ indication field.

The terminal device 1 may set the size of the HARQ-ACK codebook according to the size of the dl-DataToUL-ACK. For example, if the dl-DataToUL-ACK consists of eight elements, the size of the HARQ-ACK codebook is eight. For example, if the dl-DataToUL-ACK consists of two elements, the size of the HARQ-ACK codebook is two. Each piece of HARQ-ACK information that constitutes the HARQ-ACK codebook is HARQ-ACK information for PDSCH reception at each slot timing of the dl-DataToUL-ACK. This type of HARQ-ACK codebook is also called a Semi-static HARQ-ACK codebook.

The terminal device 1 may report HARQ-ACK information for PDSCH reception in slot n by using PUCCH transmission and/or PUSCH transmission in slot n+k. Here, k may be the number of slots indicated by the HARQ indication field included in the DCI format corresponding to the PDSCH reception. In addition, if the HARQ indication field is not included in the DCI format, k may be given by the upper layer parameter dl-DataToUL-ACK.

The terminal device 1 determines a set of multiple opportunities for one or more candidate PDSCH receptions for transmitting corresponding HARQ-ACK information in the PUCCH of a certain slot. The terminal device 1 determines multiple slots of slot timing K1 included in the dl-DataToUL-ACK as multiple opportunities for candidate PDSCH reception. K1 may be a set of k. For example, when dl-DataToUL-ACK is (1, 2, 3, 4, 5, 6, 7, 8), in the PUCCH of slot n, HARQ-ACK information is transmitted for PDSCH reception in slot n-1, PDSCH reception in slot n-2, PDSCH reception in slot n-3, PDSCH reception in slot n-4, PDSCH reception in slot n-5, PDSCH reception in slot n-6, PDSCH reception in slot n-7, and PDSCH reception in slot n-8. When the terminal device 1 actually receives a PDSCH in a slot corresponding to the candidate PDSCH reception, it sets an ACK or NACK as the HARQ-ACK report based on the transport block contained in the PDSCH, and when it does not receive a PDSCH in a slot corresponding to the candidate PDSCH reception, it sets a NACK as the HARQ-ACK information.

The HARQ-ACK codebook may be based on at least some or all of the set of monitoring occasions for PDCCH, the value of the counter DAI field. The HARQ-ACK codebook may be based on the value of the UL DAI field. The HARQ-ACK codebook may be based on the value of the DAI field. The HARQ-ACK codebook may be based on the value of the total DAI field.

The size of the HARQ-ACK codebook may be set based on the value of the counter DAI field of the last received DCI format, which indicates the cumulative number of PDSCHs or transport blocks scheduled until reception of the corresponding DCI format. The size of the HARQ-ACK codebook may be set based on the value of the total DAI field of the DCI format, which indicates the total number of PDSCHs or transport blocks scheduled until transmission of the HARQ-ACK codebook.

The terminal device 1 may determine a set of PDCCH monitoring opportunities for HARQ-ACK information transmitted in a PUCCH placed in a slot with index n (slot#n) based on at least a part or all of the value of the timing K1 and the value of the slot offset K0. The set of PDCCH monitoring opportunities for HARQ-ACK information transmitted in a PUCCH placed in a slot with index n is also referred to as a set of PDCCH monitoring opportunities for slot n (monitoring occasions for PDCCH for slot#n). Here, the set of PDCCH monitoring opportunities includes M PDCCH monitoring opportunities. For example, the slot offset K0 may be indicated based at least on the value of a time domain resource allocation field included in a downlink DCI format. The slot offset K0 is a value indicating the number of slots (slot difference) from a slot including the last OFDM symbol in which a PDCCH including a DCI format including a time domain resource allocation field indicating the slot offset K0 is placed to the first OFDM symbol of a PDSCH scheduled by the DCI format.

When a DCI format detected in a monitoring opportunity of any search space set corresponding to a monitoring opportunity of a certain PDCCH triggers (includes triggering information) to transmit HARQ-ACK information in slot n, the terminal device 1 may determine the monitoring opportunity of the PDCCH as a PDCCH monitoring opportunity for slot n. Also, when a DCI format detected in a monitoring opportunity of a search space set corresponding to a monitoring opportunity of a certain PDCCH does not trigger (does not include triggering information) to transmit HARQ-ACK information in slot n, the terminal device 1 may not determine the monitoring opportunity of the PDCCH as a PDCCH monitoring opportunity for slot n. Also, when a DCI format is not detected in a monitoring opportunity of a search space set corresponding to a monitoring opportunity of a certain PDCCH, the terminal device 1 may not determine the monitoring opportunity of the PDCCH as a PDCCH monitoring opportunity for slot n.

The Counter DAI indicates, for a PDCCH monitoring opportunity in a serving cell, the cumulative number of PDCCHs detected up to a PDCCH monitoring opportunity in the serving cell among M PDCCH monitoring opportunities (or may be a value at least related to the cumulative number). The Counter DAI may also be referred to as C-DAI. The C-DAI corresponding to a PDSCH may be indicated by a field included in a DCI format used for scheduling the PDSCH. The Total DAI may indicate the cumulative number of PDCCHs detected up to PDCCH monitoring opportunity m among M PDCCH monitoring opportunities (or may be a value at least related to the cumulative number). The Total DAI may also be referred to as T-DAI (Total Downlink Assignment Index).

Physical signal is also a general term for sidelink physical channel and sidelink physical signal. Physical channel is also a general term for sidelink physical channel. Physical signal is also a general term for sidelink physical signal.

A sidelink physical channel may correspond to a set of resource elements carrying information generated in a higher layer. A sidelink physical channel is a physical channel used in a sidelink. The sidelink physical channel may be transmitted by the radio transceiver unit 10. The sidelink physical channel may be received by the radio transceiver unit 10. In a wireless communication system according to one aspect of the present embodiment, at least some or all of the following sidelink physical channels are used.
・PSBCH (Physical Sidelink Broadcast CHannel)
・PSCCH (Physical Sidelink Control CHannel)
・PSSCH (Physical Sidelink Shared CHannel)
・PSFCH (Physical Sidelink Feedback CHannel)

The PSBCH is transmitted to convey the DFN (Direct Frame Number), the TDD UL-DL configuration, the slot index (the slot index of the slot in which the PSBCH is placed), and the in-coverage indicator (an identifier indicating whether the transmitting terminal device 1 is located within the coverage of the base station device 3).

The PSCCH is used at least for transmitting (transmitting) sidelink control information (SCI). The sidelink control information may be placed in the PSCCH. The terminal device 1 may receive the PSCCH in which the sidelink control information is placed. The terminal device 1 may transmit the PSCCH in which the sidelink control information is placed.

Sidelink control information is transmitted and received in the form of a sidelink control information format (SCI format). SCI transmitted and received on the PSCCH is called 1st stage SCI. SCI transmitted and received on the PSSCH is called 2nd stage SCI. The 1st stage SCI format may include SCI format 1-A. SCI format 1-A is used for scheduling the PSSCH and the 2nd stage SCI. SCI format 1-A includes a field indicating priority, a field indicating frequency resource allocation, a field indicating time resource allocation, a field indicating a resource reservation section, a field indicating a DM RS pattern, a field indicating the 2nd stage SCI format (SCI format 2-A, SCI format 2-B), a field indicating a beta offset (a parameter used to determine the amount of resources for the 2nd stage SCI), a field indicating the number of DM RS ports, a field indicating the MCS, a field indicating the MCS table, and a field including a PSFCH overhead indication.

The 2nd stage SCI is used for decoding the PSSCH. SCI format 2-A contains the following information: HARQ process number, NDI, RV (Redundancy version), Source ID, Destination ID, HARQ feedback enable/disable indicator, cast type indicator (unicast, broadcast, groupcast), and CSI request. SCI format 2-B contains the following information: HARQ process number, NDI, RV, Source ID, Destination ID, HARQ feedback enable/disable indicator, Zone ID, and communication range request.

The PSSCH may be transmitted to transmit sidelink data (sidelink transport block, sidelink PDU) and 2nd stage SCI. The PSSCH may be used to transmit sidelink data and 2nd stage SCI. The terminal device 1 may transmit a PSSCH in which the sidelink data and 2nd stage SCI are arranged. The terminal device 1 may receive a PSSCH in which the sidelink data and 2nd stage SCI are arranged.

The PSFCH may be used to transmit HARQ-ACK information corresponding to PSSCH reception. The terminal device 1 may transmit a PSFCH in which the HARQ-ACK information is placed. The terminal device 1 may receive a PSFCH in which the HARQ-ACK information is placed.

The sidelink physical signal may correspond to a set of resource elements. The sidelink physical signal may not be used to convey information generated in a higher layer. The sidelink physical signal may be used to convey information generated in a physical layer. The radio transceiver 10 may transmit the sidelink physical signal. The radio transceiver 10 may receive the sidelink physical signal. In the sidelink of the wireless communication system according to one aspect of the present embodiment, at least some or all of the following sidelink physical signals may be used.
・Sidelink Synchronization Signal (S-SS)
・Side link DM RS
・Sidelink CSI-RS
・Side link PT-RS

The sidelink synchronization signal is used by the terminal device 1 to synchronize the frequency domain and/or time domain of the sidelink. The sidelink synchronization signal is a general term for the S-PSS (Sidelink Primary Synchronization Signal) and the S-SSS (Sidelink Secondary Synchronization Signal).

Sidelink DM RS is a general term for DM RS for PSBCH, DM RS for PSCCH, and DM RS for PSSCH. The time domain pattern of the DM RS for PSSCH is selected by the transmitting terminal device 1. The time domain patterns of the selection candidates are configured for each resource pool.

Sidelink CSI-RS is a reference signal used for measuring the sidelink channel. It is configured with time resource allocation (symbol position to be allocated), frequency resource allocation, number of antenna ports, and number of layers for CSI-RS. The terminal device 1 reports channel state information measured based on the sidelink CSI-RS using MAC CE.

Sidelink PT-RS may be supported only in the high frequency band (FR2). The time and frequency density of sidelink PT-RS is configured per resource pool.

An AGC (Access Gain Control) signal may be used. The AGC signal may be placed in the first OFDM symbol of the slot (first slot, second slot).

The terminal device 1 may report the sidelink HARA-ACK information received from the destination terminal device 1 to the base station device 3 using the uplink PUCCH. A semi-static HARQ-ACK codebook or a dynamic HARQ-ACK codebook may be used.

The base station device 3 may notify the terminal device 1 of sidelink scheduling information using a DCI format. DCI format 3_0 is used for scheduling the PSCCH and PSSCH. DCI format 3_0 is configured to include some or all of the following information:
Resource pool index Time gap HARQ process number NDI
Subchannel allocation information SCI format 1_A field Timing indicator for feeding back HARQ-ACK of PSSCH corresponding to PSFCH reception PUCCH resource indicator Configuration index Sidelink allocation index counter

The resource pool index indicates the resource pool used for the scheduled PSCCH and PSSCH. The time gap indicates the time from reception of DCI format 3_0 to sidelink transmission. The subchannel allocation information indicates the subchannel used for the scheduled PSCCH and PSSCH. The SCI format 1_A field includes information on frequency resource allocation and time resource allocation of SCI format 1_A transmitted by the terminal device 1 on the PSCCH. The timing indicator for feeding back HARQ-ACK of PSSCH corresponding to PSFCH reception indicates the timing at which the terminal device 1 feeds back HARQ-ACK information obtained by receiving PSFCH from the counterpart terminal device 1 using PUCCH. The PUCCH resource indicator indicates the PUCCH resource used to feed back HARQ-ACK information obtained by receiving PSFCH. The configuration index indicates the configuration of the sidelink Configured grant. The sidelink allocation index counter indicates the number of sidelink allocations allocated by the base station device 3 to the terminal device 1 within a certain period.

In order to use unlicensed spectrum, certain restrictions must be met. For example, according to regulations of the European Telecommunications Standards Institute (ETSI), when using 5 GHz, which is one type of unlicensed spectrum, the occupied channel bandwidth (OCB), which contains 99% of the signal power, must be equal to or greater than 80% of the available bandwidth (e.g., system bandwidth, LBT sub-band bandwidth, sub-band bandwidth). In addition, restrictions are specified regarding the maximum transmission power density (Power Spectral Density (PSD)) per given bandwidth (1 MHz).

To satisfy such constraints (e.g., OCB rules), unlicensed carriers transmit using a set of multiple frequency domain resources (also called interlaces, RB sets, etc.) at a predetermined interval (interlaced transmission). One interlace may be defined as a set of multiple frequency domain resources allocated at a predetermined frequency interval (e.g., 10 RB intervals).

FIG. 5 is a diagram showing an example of interlace mapping according to one aspect of this embodiment. Here, a case where the total available bandwidth is 20 MHz and there are 100 RBs is described. Interlace #i is composed of 10 RBs with index values of {i, i+10, i+20, ..., i+90}. One interlace is composed of multiple RBs with a frequency interval of 10 RBs. When the total available bandwidth is 20 MHz, 10 interlaces #0-#9 are provided.

In Figure 5, the case where the subcarrier spacing is 15 kHz is described, but when the subcarrier spacing is 30 kHz, the frequency spacing of the resource blocks that make up the interlace may be different. A 20 MHz bandwidth is made up of 50 RBs, and one interlace is made up of 10 RBs. In this case, there are five interlaces provided, #0-#4. In this case, interlace #i is made up of 10 RBs with index values of {i, i+5, i+10, ..., i+45}. One interlace is made up of multiple RBs with a frequency spacing of 5 RBs.

A subchannel may consist of one or more interlaces. Subchannel indexes and interlace indexes may correspond in ascending order.

FIG. 6 is a diagram showing the arrangement of PSCCH monitored in a terminal device 1 according to one embodiment of this invention. One slot consists of 14 OFDM symbols (#0, #1, #2, #3, #4, #5, #6, #7, #8, #9, #10, #11, #12, #13). FIG. 6(a) shows a case where PSCCH is monitored in the second OFDM symbol (#1). PSCCH is monitored in a specific subchannel of the second OFDM symbol (e.g., the subchannel with the smallest subchannel index). When the terminal device 1 detects PSCCH, it receives PSSCH in other subchannels of the second OFDM symbol, and receives PSSCH and DM RS in the third and subsequent OFDM symbols. FIG. 6(b) shows a case where PSCCH is monitored in the second and third OFDM symbols (#1, #2). The PSCCH is monitored in a specific subchannel of the second and third OFDM symbols (for example, the subchannel with the smallest subchannel index). When the terminal device 1 detects the PSCCH, it receives the PSSCH in other subchannels of the second and third OFDM symbols. It receives the PSSCH and DM RS in the fourth and subsequent OFDM symbols. Note that in Figure 6 (b), it is intended to monitor one PSCCH in the second and third OFDM symbols, and not to monitor two PSCCHs.

FIG. 7 is a diagram showing an example of the arrangement of PSCCH monitored in the terminal device 1 according to one aspect of the present embodiment. One slot is composed of 14 OFDM symbols (#0, #1, #2, #3, #4, #5, #6, #7, #8, #9, #10, #11, #12, #13). FIG. 7(a) shows a case where PSCCH is monitored in the second OFDM symbol (#1) and the ninth OFDM symbol (#8) at most. PSCCH is monitored in a specific subchannel of the second OFDM symbol (for example, the subchannel with the smallest subchannel index). When the terminal device 1 can detect PSCCH in the second OFDM symbol, it receives PSSCH in other subchannels of the second OFDM symbol, receives PSSCH and DM RS in the third and subsequent OFDM symbols, and does not monitor PSCCH in the ninth OFDM symbol. If the terminal device 1 cannot detect the PSCCH in the second OFDM symbol, it monitors the PSCCH in a specific subchannel of the ninth OFDM symbol. If the terminal device 1 can detect the PSCCH in the ninth OFDM symbol, it receives the PSSCH in another subchannel of the ninth OFDM symbol, and receives the PSSCH and DM RS in the tenth and subsequent OFDM symbols.

Figure 7(b) shows a case where PSCCH is monitored in a maximum of the second and third OFDM symbols (#1, #2) and the ninth and tenth OFDM symbols (#8, #9). PSCCH is monitored in a specific subchannel of the second and third OFDM symbols (e.g., the subchannel with the smallest subchannel index). If terminal device 1 can detect PSCCH in the second and third OFDM symbols, it receives PSSCH in other subchannels of the second and third OFDM symbols, receives PSSCH and DM RS in the fourth and subsequent OFDM symbols, and does not monitor PSCCH in the ninth and tenth OFDM symbols. If terminal device 1 cannot detect PSCCH in the second and third OFDM symbols, it monitors PSCCH in a specific subchannel of the ninth and tenth OFDM symbols. When terminal device 1 detects a PSCCH in the 9th and 10th OFDM symbols, it receives the PSSCH in other subchannels of the 9th and 10th OFDM symbols, and receives the PSSCH and DM RS in the 11th and subsequent OFDM symbols. Note that in Figure 7(b), it is intended to monitor one PSCCH in the second and third OFDM symbols, and it is not intended to monitor two PSCCHs. Note that in Figure 7(b), it is intended to monitor one PSCCH in the 9th and 10th OFDM symbols, and it is not intended to monitor two PSCCHs.

Before transmitting a signal (channel access), the terminal device 1 senses the channel (carrier sense) to check whether other devices (e.g., base station device, terminal device, WiFi terminal device, WiFi access point, etc.) are transmitting. After transmitting the previous signal, the terminal device 1 randomly generates a back-off counter value within the range of the contention window size (CWS). The terminal device 1 waits until it confirms that the channel (LBT subband, RB set, e.g., a band with a bandwidth of 20 MHz) is idle, and performs carrier sense every sensing slot time. The RB set may be composed of multiple resource blocks. The RB set may be a unit used for resource allocation for sidelink transmission. The RB set may be a unit of frequency used for PSCCH/PSSCH transmission. The RB set may be a unit of frequency used for PSFCH transmission. The RB set may be a unit of frequency used for S-SSB transmission. If the channel is idle, the terminal device 1 sequentially decreases a counter value determined randomly within the contention window size (CWS), and obtains access to the channel after the counter value reaches 0, and transmits a signal. After completing signal transmission, the terminal device 1 performing communication using HARQ-ACK feedback updates the contention window size based on the HARQ-ACK feedback received from the terminal device 1 to which the signal is to be transmitted. If the HARQ-ACK status is ACK, the terminal device 1 sets the contention window size to the minimum value. If the HARQ-ACK status is NACK, the terminal device 1 sets the contention window size to the next largest value. If the contention window size reaches the maximum value that can be set, the terminal device 1 continues to use the maximum value even if the HARQ-ACK status is NACK.

The terminal device 1 acquires a transmission opportunity (Transmission Opportunity: TxOP, Channel Occupancy) when the LBT result is idle and transmits, and does not transmit when the LBT result is busy (LBT-busy). The time of the transmission opportunity is called Channel Occupancy Time (COT). The LBT for acquiring the COT may be referred to as a Type 1 channel access procedure. The Type 1 channel access procedure may be referred to as a Type 1 LBT. The COT is the total time length between all transmissions within a transmission opportunity and gaps within a specified time, and may be less than or equal to the Maximum COT (MCOT). The MCOT may be determined based on a channel access priority class. The channel access priority class may be associated with a contention window size. The Type 1 channel access procedure performed for sidelink transmission may be referred to as a Type 1 SL channel access procedure. The Type 1 SL channel access procedure may be referred to as a Type 1 SL LBT. The Type 1 channel access procedure may be sensing of the channel to obtain the COT.

The Type 1 SL channel access procedure may be a channel access procedure by the terminal device 1 when the duration of the sensing slot detected as being idle before the sidelink transmission is random. The Type 1 SL channel access procedure may be applied to sidelink transmissions including at least either PSCCH/PSSCH or PSFCH or S-SSB. After the terminal device 1 first senses that the channel is idle during the sensing slot period of the defer interval and after the counter N becomes 0 in the fourth step of the Type 1 channel access procedure, the terminal device 1 may transmit. The terminal device 1 may set an initial counter N to the counter N as a first step of the Type 1 channel access procedure. The initial counter N may be a value randomly selected from 0 to the contention window size. After the first step of the Type 1 channel access procedure, the terminal device 1 proceeds to the fourth step of the Type 1 channel access procedure. As a second step of the Type 1 channel access procedure, if the value of counter N is greater than 0, the terminal device 1 decrements the value of counter N by one. As a third step of the Type 1 channel access procedure, the terminal device 1 detects the channel for the additional sensing slot period, and if the channel is idle during the additional sensing slot period, the terminal device 1 proceeds to a fourth step of the Type 1 channel access procedure. As a third step of the Type 1 channel access procedure, the terminal device 1 detects the channel for the additional sensing slot period, and if the channel is not idle during the additional sensing slot period, the terminal device 1 proceeds to a fifth step of the Type 1 channel access procedure. As a fourth step of the Type 1 channel access procedure, if the value of counter N is 0, the terminal device 1 may stop the Type 1 channel access procedure. In the fourth step of the Type 1 channel access procedure, if the value of the counter N is not 0, the terminal device 1 proceeds to the second step of the Type 1 channel access procedure. In the fifth step of the Type 1 channel access procedure, the terminal device 1 senses the channel until a busy sensing slot is detected within the additional defer interval or until all sensing slots of the additional defer interval are detected to be idle. In the sixth step of the Type 1 channel access procedure, if the channel is detected to be idle during all sensing slots of the additional defer interval, the terminal device 1 proceeds to the fourth step of the Type 1 channel access procedure. In the sixth step of the Type 1 channel access procedure, if the channel is not detected to be idle during all sensing slots of the additional defer interval, the terminal device 1 proceeds to the fifth step of the Type 1 channel access procedure. The terminal device 1 may determine the contention window size before the first step of the Type 1 channel access procedure. The Type 1 SL channel access procedure may be referred to as the Type 1 channel access procedure.

Sensing may be performed in 9 μs sensing slot units. During sensing of the channel in the sensing slot period, if the detected power is less than the threshold for at least 4 μs within the sensing slot period, the channel may be determined to be idle. If sensing of the channel in the sensing slot period does not show that the channel is idle, the channel may be determined to be busy.

Channel access priority classes are defined and used. For example, four channel access priority classes (channel access priority class 1, channel access priority class 2, channel access priority class 3, channel access priority class 4) are defined and used. In channel access priority class 1, the minimum contention window size is 3 slots, the maximum contention window size is 7 slots, and there are two permitted contention window sizes: {3 slots, 7 slots}. In channel access priority class 2, the minimum contention window size is 7 slots, the maximum contention window size is 15 slots, and there are two permitted contention window sizes: {7 slots, 15 slots}. In channel access priority class 3, the minimum contention window size is 15 slots, the maximum contention window size is 1023 slots, and there are seven permitted contention window sizes: {15 slots, 31 slots, 63 slots, 127 slots, 255 slots, 511 slots, 1023 slots}. In channel access priority class 4, the minimum contention window size is 15 slots, the maximum contention window size is 1023 slots, and there are seven permitted contention window sizes: {15 slots, 31 slots, 63 slots, 127 slots, 255 slots, 511 slots, 1023 slots}. Note that the contention window size may represent the number of counts per slot.

If the terminal device 1 determines that the channel is busy by carrier sensing during the sensing slot time, it senses whether the channel is idle in the defer section. The defer section consists of 16 us and multiple sensing slots. The number of sensing slots that make up the defer section depends on the channel access priority class. In channel access priority class 1, about two sensing slots are configured in the defer section. In channel access priority class 2, about two sensing slots are configured in the defer section. In channel access priority class 3, about three sensing slots are configured in the defer section. In channel access priority class 4, about seven sensing slots are configured in the defer section. If the terminal device 1 determines that the channel is busy in the defer section, it again determines whether the channel is idle in a new defer section. If the terminal device 1 determines that the channel is idle in the defer section, it decreases the counter value set based on the contention window size, and continues to perform carrier sensing every sensing slot time to determine whether the channel is idle.

For example, for channel access priority class 1, a maximum COT of 2 ms is used. For example, for channel access priority class 2, a maximum COT of 4 ms is used. For example, for channel access priority class 3, a maximum COT of 6 ms is used. For example, for channel access priority class 3, a maximum COT of 10 ms is used. For example, for channel access priority class 4, a maximum COT of 6 ms is used. For example, for channel access priority class 4, a maximum COT of 10 ms is used.

Sidelink resource allocation mode 2 is a method in which the terminal device 1 autonomously determines resources for PSCCH/PSSCH transmission. The upper layer of the terminal device 1 requests the physical layer of the terminal device 1 to determine a resource set SA, and determines resources for PSCCH/PSSCH transmission from the multiple resource sets SA. The physical layer of the terminal device 1 performs a resource selection procedure to determine a subset of resources to notify the upper layer in sidelink resource allocation mode 2. The physical layer of the terminal device 1 may be provided with parameters from the upper layer to determine a subset of resources to notify the upper layer in sidelink resource allocation mode 2. The parameters provided from the upper layer to the physical layer may be L1 priority prioTX, remaining packet delay budget, the number of subchannels to be used for PSCCH/PSSCH transmission in one slot L_subCH, and a period for resource reservation Prsvp_TX. The upper layer is a layer higher than the physical layer of the terminal device 1 and may be the MAC layer. The upper layer may also be the RRC layer. The terminal device 1 may transmit a transport block on resources selected in sidelink resource allocation mode 2. The transport block may be transmitted on a PSSCH. The transport block may be referred to as a MAC PDU. The MAC PDU may consist of one SL-SCH subheader and one or more MAC sub PDUs. The L1 priority may be the priority of the PSSCH transmission.

The L1 priority may be the priority indicated in the Priority field of SCI format 1-A. The L1 priority may be the priority of PSSCH transmission. The L1 priority may be the priority of PSCCH/PSSCH transmission. The priority level of NR PC5 may have the same format and the same meaning as the priority value of LTE PC5 PPPP (Prose Per-Packet Priority). The PPPP value may reflect the latency requirement and PDB (Packet Delay Budget) of LTE PC5. A lower PDB may be mapped to a higher priority PPPP value. The priority level of NR PC5 may be associated with a PDB and a PQI. The PDB may be derived from a PQI table. The priority level may be used to process different V2X service data across different communication modes. The communication mode may be unicast, broadcast, or group cast. If the terminal device 1 cannot satisfy all QoS requirements for all PC5 service data associated with the PC5 reference point, the priority level may be used to select which PC5 service data to prioritize the QoS requirements for. For example, a PC5 service data packet with a priority level value of N may be prioritized over PC5 service data packets with a priority level value of N+1 or N+2. The priority level may be referred to as L1 priority. V2X may be realized by V2V (Vehicle-to-Vehicle), V2P (Vehicle-to-Pedestrian), V2I (Vehicle-to-Infrastructure), and V2N (Vehicle-to-Network). The PQI is a special 5QI and may be used as a reference to the PC5 QoS characteristics. The PQI may be referred to as the PC5 5QI. A standardized PQI value may be one-to-one mapped to a combination of standardized PC5 QoS characteristics.

The set SA that the physical layer of the terminal device 1 notifies the upper layer of the terminal device 1 may be a set of resource candidates for PSCCH/PSSCH transmission. The set SA may include multiple resource candidates. The terminal device 1 may determine the resource candidates for PSCCH/PSSCH transmission included in the set SA. The terminal device 1 may exclude from the set SA resource candidates of the terminal device 1 that overlap with resources reserved by other terminal devices 1 for PSCCH/PSSCH transmission. The resources reserved by other terminal devices 1 for PSCCH/PSSCH transmission may be referred to as reserved resources of the other terminal devices 1. The resource candidates for PSCCH/PSSCH transmission may be referred to as candidate resources.

FIG. 8 is a diagram showing an example of a resource selection procedure in a resource pool of a terminal device 1 according to one aspect of the present embodiment. FIG. 8 may be a case where contiguous RBs are set in the resource pool. The terminal device 1 may include any of the terminal devices 1A to 1D in FIG. 1. The other terminal device 1 may include any of the terminal devices 1A to 1D in FIG. 1. In FIG. 8, one horizontal square is one slot, and one vertical square is one subchannel. Sub-channel#0 is a subchannel in the resource pool and has an index of 0. Slot#0 is a slot belonging to the resource pool and has an index of 0. In FIG. 8, as an example, the number of subchannels L_subCH used for PSCCH/PSSCH transmission is set to 2. For example, in FIG. 8, the number of subchannels of one candidate resource in each slot in the time interval of the terminal device 1 may be 2.

When the terminal device 1 triggers the resource selection procedure in slot n as the first step of the resource selection procedure, the period from slot n+T1 to slot n+T2 may be the time interval. For example, in FIG. 8, slot 801 may be the slot in which the terminal device 1 triggers the resource selection procedure. In FIG. 8, period 802 may be the time interval period. The time interval may be a period for determining candidate resources for PSCCH/PSSCH transmission. In the slots of the resource pool within the time interval, the terminal device 1 sets consecutive subchannels for the number of L_subCHs as one candidate resource. In other words, one candidate resource may be defined as a resource that is consecutive for the number of L_subCHs from the index of a certain subchannel in a certain slot. One candidate resource may be indicated by a slot index and a starting index of the subchannel. For example, in FIG. 8, the candidate resource 803 may be one of the candidate resources that use sub-channel#0 and sub-channel#1 in slot#8. Candidate resource 804 may be one of the candidate resources using sub-channel #1 and sub-channel #2 in slot #8. Candidate resource 805 may be one of the candidate resources using sub-channel #0 and sub-channel #1 in slot #11. Candidate resource 806 may be one of the candidate resources using sub-channel #1 and sub-channel #2 in slot #11. Similarly, terminal device 1 may determine that there is a candidate resource using sub-channel #0 and sub-channel #1 in slot #9. Terminal device 1 may determine that there is a candidate resource using sub-channel #1 and sub-channel #2 in slot #9. Terminal device 1 may determine that there is a candidate resource using sub-channel #0 and sub-channel #1 in slot #10. Terminal device 1 may determine that there is a candidate resource using sub-channel #1 and sub-channel #2 in slot #10. Terminal device 1 may determine that there is a total of eight candidate resources in the time interval. The terminal device 1 may determine T1 in the range of 0 to Tproc1. Tproc1 is the number of slots and is defined for each subcarrier interval of the sidelink BWP. The terminal device 1 may determine T2 based on T2min and the remaining packet delay budget. For example, if T2min is shorter than the remaining packet delay budget time, the terminal device 1 may determine T2 in the range of T2min to the remaining packet delay budget time. If T2min is not shorter than the remaining packet delay budget time, the terminal device 1 may set T2 to the remaining packet delay budget time. For T2min, a value corresponding to the PSSCH transmission priority L1 priority prioTX may be determined from the RRC parameter sl-SelectionWindowList. The sl-SelectionWindowList is a list of parameters for determining the end of a time interval, in which L1 priority and window size are set. sl-SelectionWindowList may be included in the configuration information of the resource pool. L1 priority prioTX may be the priority of PSCCH/PSSCH transmission of the terminal device 1. The terminal device 1 may set the number of all candidate resources in the time interval as M_total. For example, in FIG. 8, M_total is 8 because there are two candidate resources in one slot and the time interval period is four slots. For example, when L_subCH is 1, the terminal device 1 sets one subchannel as one candidate resource in each slot in the time interval. In FIG. 8, when L_subCH is 1, the terminal device 1 determines that there are three candidate resources in each slot. The terminal device 1 determines that there are three candidate resources in one slot and the time interval period is four slots, so M_total is 12. In other words, the first step of the resource selection procedure is a step for determining candidate resources within a time interval.

In the second step of the resource selection procedure, the terminal device 1 may define the range from slot n-T0 to slot n-Tproc0 as a sensing window. For example, in FIG. 8, period 807 may be the period of the sensing window. T0 is the number of slots and may be determined based on the RRC parameter sl-SensingWindow. Tproc0 is used to determine the end of the sensing window and is defined by the subcarrier spacing of the sidelink BWP. sl-SensingWindow is a parameter for determining the start of the sensing window and may be included in the configuration information of the resource pool. The terminal device 1 monitors the slots belonging to the sidelink resource pool, excluding the slot in which the terminal device 1 itself has transmitted within the sensing window. In other words, the second step of the resource selection procedure is a step for defining the sensing window.

The terminal device 1 may determine an RSRP threshold as a third step of the resource selection procedure. In a sixth step, the terminal device 1 determines an RSRP threshold in order to exclude candidate resources based on the RSRP threshold. The terminal device 1 may determine the RSRP threshold from the PSSCH transmission priority L1 priority prioTX of the terminal device 1, the PSSCH transmission priority L1 priority prioRX of the other terminal device 1 notified by the SCI, and the RRC parameter sl-Thres-RSRP-List. The terminal device 1 may determine an RSRP threshold for each of the PSSCH transmission priority L1 priority prioTX of the terminal device 1 and the PSSCH transmission priority L1 priority prioRX of the other terminal device 1 notified by the SCI. sl-Thres-RSRP-List indicates a list of 64 types of thresholds, and which threshold to use may be determined from the PSSCH transmission priority L1 priority prioTX of the terminal device 1 and the PSSCH transmission priority L1 priority prioRX of the other terminal device 1. sl-Thres-RSRP-List may be included in the configuration information of the resource pool. In other words, the third step of the resource selection procedure is a step for determining the RSRP threshold.

In the fourth step of the resource selection procedure, the terminal device 1 may set all candidate resources in the set SA of candidate resources. In the fourth step of the resource selection procedure, the terminal device 1 may initialize the set S_A to include all the candidate resources determined in the first step. In other words, the fourth step of the resource selection procedure is a step for setting all the candidate resources determined in the first step in the set SA, which is a collection of candidate resources.

As a fifth step of the resource selection procedure, the terminal device 1 may assume that the terminal device 1 itself has transmitted within the sensing window and has received SCI format 1-A in a slot that is not monitored within the sensing window, and may exclude from the set SA candidate resources belonging to slots in all periods of the RRC parameter sl-ResourceReservePeriodList, starting from the slot in which it is assumed that SCI format 1-A was received. The sl-ResourceReservePeriodList indicates a set of periods of reserved resources valid in the resource pool, and up to 16 values may be set for each resource pool. The sl-ResourceReservePeriodList may be included in the configuration information of the resource pool. For example, in FIG. 8, slot 808 may be a slot that the terminal device 1 is not monitoring. The terminal device 1 assumes that it has received SCI format 1-A in slot 808, and excludes from the set SA candidate resources belonging to slots in all periods of the sl-ResourceReservePeriodList, starting from slot 808. In FIG. 8, sl-ResourceReservePeriodList indicates 8-period slots and 9-period slots. Slot 809 is a slot that is 8 period slots from slot 808. Terminal device 1 excludes candidate resources that belong to slot 809 from set SA. Slot 810 is a slot that is 9 period slots from slot 808. Terminal device 1 excludes candidate resources that belong to slot 810 from set SA. In other words, the fifth step of the resource selection procedure is a step for excluding candidate resources from set SA in consideration of slots that are not monitored in the sensing window.

If the number of candidate resources remaining in the set SA after the fifth step of the resource selection procedure is smaller than X·M_total, the terminal device 1 may set all the candidate resources determined in the first step in the set SA. X may indicate the percentage of the candidate resources to the total number M_total of all the candidate resources determined in the first step. X may be set in the RRC parameter sl-TxPercentateList. sl-TxPercentateList may be included in the configuration information of the resource pool. If the number of candidate resources remaining in the set SA is equal to or greater than X·M_total, the terminal device 1 maintains the candidate resources in the set SA.

As a sixth step of the resource selection procedure, the terminal device 1 determines the location of the reserved resource of the other terminal device 1 based on the resource reservation period field, the time domain resource allocation field, and the frequency domain resource allocation field of the SCI format 1-A of the other terminal device 1 received in the sensing window. When the RSRP measurement value of the SCI format 1-A of the other terminal device 1 is higher than the set RSRP threshold, the terminal device 1 may exclude candidate resources that overlap with the reserved resource of the other terminal device 1 from the set SA. For example, in FIG. 8, resource 811 is a resource in which the terminal device 1 receives the SCI format 1-A of the other terminal device 1 on sub-channel #1 in slot #3 in the sensing window. The terminal device 1 may determine the location of the reserved resource of the other terminal device 1 from the SCI format 1-A received in resource 811. Resource 812 is a reserved resource of the other terminal device 1 indicated by the SCI format 1-A received in resource 811. Resource 812 is a reserved resource of the other terminal device 1 present in sub-channel #0 of Slot #11. When the terminal device 1 determines that the RSRP measurement value of the SCI format 1-A of the other terminal device 1 received in resource 811 is higher than the set RSRP threshold, the terminal device 1 excludes the candidate resource 805 overlapping with the reserved resource 812 of the other terminal device 1 from the set SA. Resource 813 is a resource from which the terminal device 1 received the SCI format 1-A of the other terminal device 1 in sub-channel #2 in slot #4 in the sensing window. The other terminal device 1 that transmitted the SCI format 1-A in resource 811 and the other terminal device 1 that transmitted the SCI format 1-A in resource 813 may be different terminal devices. The terminal device 1 may determine the position of the reserved resource of the other terminal device 1 from the SCI format 1-A received in resource 813. Resource 814 is a reserved resource of the other terminal device 1 indicated by SCI format 1-A received in resource 813. Resource 814 is a resrved resource of the other terminal device 1 present in sub-channel #2 of Slot #11. When the terminal device 1 determines that the RSRP measurement value of SCI format 1-A of the other terminal device 1 received in resource 813 is equal to or less than the set RSRP threshold, the terminal device 1 does not exclude the candidate resource 806 from the set SA even if the reserved resource 814 of the other terminal device 1 and the candidate resource 806 overlap. In other words, the sixth step of the resource selection procedure is a step for determining whether to exclude a candidate resource from the set SA based on the SCI format 1-A of the other terminal device 1 received in the sensing window.

In the seventh step of the resource selection procedure, if the number of candidate resources remaining in the set SA is smaller than X·M_total, the terminal device 1 increases the RSRP threshold by 3 dB and redoes the resource selection from the fourth step of the resource selection procedure. If the number of candidate resources remaining in the set SA is equal to or greater than X·M_total, the physical layer of the terminal device 1 may notify the upper layer of the terminal device 1 of the set SA. In other words, the seventh step of the resource selection procedure is a step for deciding whether or not to redo the resource selection. The set SA may be referred to as a set of candidate resources.

When the terminal device 1 redoes the resource selection, the RSRP threshold for excluding candidate resources in the sixth step may be increased by 3 dB. For example, by increasing the RSRP threshold by 3 dB, the number of candidate resources to be excluded in the second sixth step of the terminal device 1 becomes smaller than the number of candidate resources to be excluded in the first sixth step, and the number of candidate resources remaining in the set SA in the second resource selection can be increased compared to the first resource selection. For example, in FIG. 8, if the number of candidate resources remaining in the set SA as a result of the first resource selection is smaller than a predetermined number, the terminal device 1 amplifies the RSRP threshold by 3 dB and redoes the resource selection from the fourth step. In FIG. 8, in the first sixth step of the terminal device 1, the RSRP measurement value of the SCI format 1-A of the other terminal device 1 received at resource 811 exceeded the RSRP threshold, so that the terminal device 1 excluded candidate resource 805 that overlaps with reserved resource 812 of the other terminal device 1 from the set SA. In the sixth step for the second time, when the RSRP measurement value of SCI format 1-A received in resource 811 does not exceed the RSRP threshold, terminal device 1 does not exclude candidate resource 805 that overlaps with reserved resource 812 of another terminal device 1 from set SA. In other words, terminal device 1 can increase the number of candidate resources remaining in set SA by increasing the RSRP threshold and redoing resource selection.

The upper layer of the terminal device 1 may select (determine) resources for PSCCH/PSSCH transmission from the set SA notified from the physical layer of the terminal device 1 and notify the physical layer of the terminal device 1. The upper layer of the terminal device 1 may generate an SL grant to indicate the selected resources and pass the generated SL grant to the physical layer of the terminal device 1. The physical layer of the terminal device 1 determines resources for PSCCH/PSSCH transmission (i.e., resources selected by the upper layer of the terminal device 1) based on the SL grant. The terminal device 1 may perform PSCCH/PSSCH transmission with resources selected (determined) from the upper layer. PSCCH/PSSCH transmission with the first resource among the resources selected (determined) from the upper layer for a certain resource selection procedure may be referred to as initial transmission. PSCCH/PSSCH transmission with resources other than the first resource may not be referred to as initial transmission. That is, among the resources selected (determined) by a higher layer for a certain resource selection procedure, resources other than the first resource may be referred to as reserved resources (reserved resources of the terminal device 1 itself). The terminal device 1 may treat the first PSCCH/PSSCH transmission in the candidate resources after autonomously selecting resources for PSCCH/PSSCH transmission (mode 2) as the initial transmission. The terminal device 1 may set the reserved resources of the terminal device 1 after the resource reservation period after the initial transmission. In one aspect of the present invention, the initial transmission may be the first transmission using the determined resources.

The terminal device 1 may perform multi-consecutive slot transmission (MCSt) in consecutive slots including sidelink transmission. MCSt may also be referred to as transmission in multiple consecutive slots.

The transport blocks transmitted in each slot of the MCSt may be different transport blocks. Also, the transport blocks transmitted in each slot of the MCSt may include the same transport block. The MCSt of different transport blocks may be referred to as an MCSt of Multiple TBs (Transport Blocks). The terminal device 1 may perform a resource selection procedure for each transport block to be transmitted in the MCSt. The physical layer of the terminal device 1 may determine a set of candidate resources SA for each resource selection procedure. In order to determine the resources of the MCSt, the MAC layer of the terminal device 1 may select resources from the set of candidate resources SA notified by the physical layer for each transport block so that they are consecutive in the slot. The MCSt may be referred to as a sidelink transmission burst. For example, when performing an MCSt of Multiple TBs, the terminal device 1 performs a first resource selection procedure to determine resources to be used for transmitting a first transport block, and the terminal device 1 determines a first set of candidate resources SA. The terminal device 1 performs a second resource selection procedure to determine resources to be used for transmitting a second transport block, and the terminal device 1 determines a second set of candidate resources SA. The terminal device 1 selects resources for performing MCSt from the determined first candidate resource set SA and the second candidate resource set SA. Alternatively, when performing MCSt, the terminal device 1 performs a first resource selection procedure to determine resources to be used for transmitting the first transport block, and determines the first candidate resource set. The terminal device 1 determines resources for performing MCSt from the determined first candidate resource set.

FIG. 9 is a diagram showing an example of the arrangement of slots of MCSt of the terminal device 1 according to one aspect of the present embodiment. The terminal device 1 may include any of the terminal devices 1A to 1D of FIG. 1. In FIG. 9, one horizontal square is one slot. Slot #0 is a slot that belongs to the resource pool and has an index of 0. Slot #1 is a slot that belongs to the resource pool and has an index of 1. Slot #2 is a slot that belongs to the resource pool and has an index of 2. Slot #3 is a slot that belongs to the resource pool and has an index of 3. Slot #4 is a slot that belongs to the resource pool and has an index of 4. Slot #0, slot #1, slot #2, slot #3, and slot #4 are consecutive slots. Slot #1 is a slot in which the PSSCH is transmitted. Slot #2 is a slot in which the PSSCH is transmitted. Slot #3 is a slot in which the PSSCH is transmitted. The frequency domain in FIG. 9 may be 1RB set. The frequency domain in FIG. 10 may be 1 channel.

For example, in FIG. 9, the terminal device 1 may perform MCSt in consecutive slots #1, #2, and #3 including PSSCH. The terminal device 1 may transmit different transport blocks in slot #1, #2, and #3. The terminal device 1 may also transmit the same transport block in slot #1, #2, and #3. For example, the terminal device 1 may transmit transport block #1 in slot #1, transport block #2 in slot #2, and transport block #3 in slot #3. The terminal device 1 may also transmit transport block #1 in slot #1, #2, and #3. The terminal device 1 may also transmit transport block #1 in slot #1 and #2, and transport block #2 in slot #3. Here, transport block #1, transport block #2, and transport block #3 are different transport blocks.

When interlacing is configured in the resource pool, the number of RB sets L_RBset used for one candidate resource may be included in the parameters provided from the higher layer to the physical layer for performing the sidelink resource allocation mode 2. The higher layer may be a layer higher than the physical layer of the terminal device 1. The higher layer may also be the MAC layer. The higher layer may also be the RRC layer. When the physical layer of the terminal device 1 is provided with L_RBset, the terminal device 1 may define one candidate resource using the number of RB sets indicated by L_RBset in the first step of the resource selection procedure. The number of subchannels L_subCH provided from the higher layer to the physical layer may be the number of subchannels used in one RB set. In the first step of the resource selection procedure, one candidate resource may be defined as consecutive subchannels in each RB set in consecutive RB sets in the number of L_RBset in a certain slot. Also, one candidate resource may be defined by a slot index, a start index of an RB set, and a start index of a subchannel. For example, when the physical state of terminal device 1 is provided with L_RB set=2 and L_subCH=2 from a higher layer, one candidate resource for terminal device 1 may be a resource having subchannel index #0 and subchannel index #1 in RB set #0, and a resource having subchannel index #0 and subchannel index #1 in RB set #1.

The number of consecutive slots Nslot,MCSt may be included in the parameters provided from the upper layer to the physical layer. The upper layer may be a layer higher than the physical layer of the terminal device 1. The upper layer may be a MAC layer. The upper layer may be an RRC layer. When the physical layer of the terminal device 1 is provided with Nslot,MCSt, the physical layer of the terminal device 1 may define the time domain of one candidate resource as a resource having consecutive slots of the number of Nslot,MCSt in the first step of the resource selection procedure. When Nslot,MCSt is provided, one candidate resource may be referred to as a multi-slot candidate resource. The index of the time domain of one multi-slot candidate resource may be indicated by the index of the first slot of the multi-slot candidate resource. The frequency resources of the multi-slot candidate resource may all be the same in each slot. Furthermore, the frequency resources of the multi-slot candidate resource may be different in each slot. For example, in the terminal device 1, when contiguous RBs are configured in the resource pool, if Nslot,MCSt=2 and L_subCH=2 are provided from the upper layer to the physical layer of the terminal device 1, one multi-slot candidate resource may be a resource having subchannel index #1 and subchannel index #2 in slot #1, and having subchannel index #1 and subchannel index #2 in slot #2. In the terminal device 1, when interlacing is configured in the resource pool, if Nslot,MCSt=2, L_RB set=2 and L_subCH=2 are provided from the upper layer to the physical layer of the terminal device 1, one multi-candidate resource may be a resource having subchannel index #1 and subchannel index #2 in each RB set of RB set #0 and RB set #1 in slot #1, and having subchannel index #1 and subchannel index #2 in each RB set of RB set #0 and RB set #1 in slot #2.

A resource pool may include one or more RB sets in the frequency domain. A channel may be a carrier or a part of a carrier consisting of a set of contiguous resource blocks in which channel access is performed in the shared spectrum. That is, a channel may be a unit in which sensing is performed. Sensing may be a Type 1 channel access procedure. Sensing may also be a Type 2 channel access procedure. Sensing may also be a Type 2A channel access procedure. Sensing may also be a Type 2B channel access procedure. Sensing may also be a Type 2C channel access procedure. A channel may be referred to as an RB set. An RB set may be configured in a sidelink BWP. An RB set may be defined by the start CRB and end CRB of an RB set. The terminal device 1 may perform sensing for each RB set. When the terminal device 1 performs sidelink transmission simultaneously on multiple channels, the terminal device 1 may perform multi-channel access. Multi-channel access may be a method of sensing multiple channels used for sidelink transmission. The RB set may be referred to as a sub-band. The Type 2A channel access procedure may be referred to as Type 2A LBT. The Type 2B channel access procedure may be referred to as Type 2B LBT. The Type 2C channel access procedure may be referred to as Type 2C LBT. The channel may be a unit of 20 MHz in the frequency domain including the RB set and guard bands.

The terminal device 1 may perform a Type 1 channel access procedure before transmission in the first slot of MCSt. The terminal device 1 may perform a Type 1 channel access procedure for the RB set to which the PSSCH in the first slot of MCSt belongs. The terminal device 1 may perform MCSt if the Type 1 channel access procedure is successful before transmission in the first slot of MCSt. The terminal device 1 may perform multi-channel access before transmission in the first slot of MCSt. The terminal device 1 may perform multi-channel access for multiple RB sets to which the PSSCH in the first slot of MCSt belongs. The terminal device 1 may perform MCSt if multi-channel access is successful before transmission in the first slot of MCSt. The terminal device 1 may perform Type 1 channel access procedure or multi-channel access before transmission in the second slot if the Type 1 channel access procedure or multi-channel access in the first slot of MCSt fails. That is, when the Type 1 channel access procedure or multi-channel access for MCSt fails, the terminal device 1 may perform the Type 1 channel access procedure or multi-channel access for transmission from the slot next to the slot where transmission could not be performed. For example, in FIG. 9, the terminal device 1 may perform the Type 1 channel access procedure or multi-channel access before transmission in slot #1. The terminal device 1 may perform the Type 1 channel access procedure or multi-channel access for the RB set to which the PSSCH in slot #1 belongs. The terminal device 1 may perform MCSt when the Type 1 channel access procedure or multi-channel access is successful. When the Type 1 channel access procedure or multi-channel access fails before transmission in slot #1, the terminal device 1 may perform the Type 1 channel access procedure or multi-channel access for transmission in slot #2. If the Type 1 channel access procedure or multi-channel access fails before transmission in slot #2, the terminal device 1 may perform the Type 1 channel access procedure or multi-channel access for transmission in slot #3.

When the terminal device 1 applies a Type 1 channel access procedure to transmit a PSCCH/PSSCH of a single TB (Transport Block), the terminal device 1 may perform the Type 1 channel access procedure using a channel access priority class value associated with the single TB. The terminal device 1 may perform MCSt to transmit a single TB in multiple consecutive slots. For example, in FIG. 9, the terminal device 1 may transmit a first transport block using slot #1, slot #2, and slot #3.

When the terminal device 1 applies the Type 1 channel access procedure to transmit Multiple TBs in multiple consecutive slots, the terminal device 1 may perform the Type 1 channel access procedure using the maximum channel access priority class value among the channel access priority class values associated with the Multiple TBs. For example, in FIG. 9, if the terminal device 1 performs MCSt of a first transport block associated with a channel access priority class value of 1 in slot #1, a second transport block associated with a channel access priority class value of 2 in slot #2, and a third transport block associated with a channel access priority class value of 3 in slot #3, the terminal device 1 performs the Type 1 channel access procedure using the channel access priority class value of 3.
ESS procedure may be performed.

FIG. 10 is a diagram showing an example of an arrangement of consecutive slot transmissions including multiple sidelink transmissions of a terminal device 1 according to one aspect of the present embodiment. The terminal device 1 may include any of the terminal devices 1A to 1D of FIG. 1. In FIG. 10, one horizontal square represents one slot. Slot #0 is a slot that belongs to the resource pool and has an index of 0. Slot #1 is a slot that belongs to the resource pool and has an index of 1. Slot #2 is a slot that belongs to the resource pool and has an index of 2. Slot #3 is a slot that belongs to the resource pool and has an index of 3. Slot #4 is a slot that belongs to the resource pool and has an index of 4. Slot #0, slot #1, slot #2, slot #3, and slot #4 are consecutive slots. Slot #1 is a slot in which a PSFCH is transmitted. Slot #2 is a slot in which a PSSCH is transmitted. Slot #3 is a slot in which an S-SSB is transmitted. The frequency domain in FIG. 10 may be 1 RB set. The frequency domain in FIG. 10 may be 1 channel.

When the terminal device 1 applies the Type 1 channel access procedure to transmit multiple sidelink transmissions in multiple consecutive slots, the terminal device 1 may use the largest channel access priority class value among the channel access priority class values associated with the multiple sidelink transmissions when performing the Type 1 channel access procedure. For example, in FIG. 10, when the terminal device 1 performs a PSFCH transmission associated with channel access priority class value 1 in slot #1, a PSSCH transmission associated with channel access priority class value 3 in slot #2, and an S-SSB transmission associated with channel access priority class value 1 in slot #3, the terminal device 1 may perform multiple sidelink transmissions using the channel access priority class value 3 in the Type 1 channel access procedure.

The S-SSB may consist of P-SSS, S-SSS and PSBCH. The channel access priority class value of the S-SSB transmission may be 1. The channel access priority class value of the PSFCH transmission may be 1.

The channel access priority class value for channel access priority class 1 may be 1. The channel access priority class value for channel access priority class 2 may be 2. The channel access priority class value for channel access priority class 3 may be 3. The channel access priority class value for channel access priority class 4 may be 4. The channel access priority class values may be related to the number of sensing slots for the defer interval and the minimum and maximum contention window sizes and the maximum channel occupancy period and allowed contention window size.

If the terminal device 1 is scheduled to perform a transmission in a set of channels C and the sidelink transmission is scheduled to start transmission simultaneously on all channels in the set of channels C, the terminal device 1 may access the multiple channels on which the sidelink transmission is performed according to a multi-channel access procedure for sidelink transmission. Also, if the terminal device 1 intends to perform a sidelink transmission on resources configured in the set of channels C and the sidelink transmission is configured to start transmission simultaneously on all channels in the set of channels C, the terminal device 1 may access the multiple channels on which the sidelink transmission is performed according to a multi-channel access procedure for sidelink transmission. Also, if the terminal device 1 intends to perform a sidelink transmission on resources selected in the set of channels C and the sidelink transmission is scheduled to start transmission simultaneously on all channels in the set of channels C, the terminal device 1 may
A plurality of channels over which sidelink transmissions are to be carried out may be accessed according to a multi-channel access procedure for sidelink transmissions, where the set of channels C may be a set including one or more channels.

The multi-channel access procedure for sidelink transmission may be applied to PSCCH/PSSCH transmission. The multi-channel access procedure for sidelink transmission may be applied to S-SSB transmission. The multi-channel access procedure for sidelink transmission may be applied to PSFCH transmission.

The multi-channel access procedure for sidelink transmission may be referred to as a multi-channel access procedure.

FIG. 11 is a diagram showing an example of sidelink transmission on multiple channels of terminal device 1 according to one aspect of this embodiment. Terminal device 1 may include any of terminal devices 1A to 1D in FIG. 1. In FIG. 11, one horizontal square is one slot. Slot #0 is a slot that belongs to the resource pool and has an index of 0. Slot #1 is a slot that belongs to the resource pool and has an index of 1. Slot #2 is a slot that belongs to the resource pool and has an index of 2. Slot #3 is a slot that belongs to the resource pool and has an index of 3. Slot #4 is a slot that belongs to the resource pool and has an index of 4. RB set #0 is an RB set that belongs to the resource pool and has an index of 0. RB set #1 is an RB set that belongs to the resource pool and has an index of 1. RB set #2 is an RB set that belongs to the resource pool and has an index of 2. 111 may be a sidelink transmission that starts simultaneously using RB set #0, RB set #1, and RB set #2. 111 may be a PSCCH/PSSCH transmission. 111 may be a PSSCH transmission. 111 may be a PSFCH transmission. 111 may be an S-SSB transmission. Channel set C may be composed of channels on which sensing is performed for transmissions in RB set#0, RB set#1, and RB set#2. Channel set C may be composed of RB set#0, RB set#1, and RB set#2. Terminal device 1 may perform a multi-channel access procedure for transmissions of 111. RB set#0 may be referred to as channel#0. RB set#1 may be referred to as channel#1. RB set#2 may be referred to as channel#2.

When terminal device 1 intends to perform sidelink transmission on channel set C and a Type 1 channel access procedure is used for sidelink transmission on channel set C, it may perform transmission using a Type 1 channel access procedure on each channel of channel set C. For example, in FIG. 11, terminal device 1 may perform a Type 1 channel access procedure on each of RB set#0, RB set#1, and RB set#2.

The terminal device 1 may intend to perform sidelink transmission in the set of channels C, and when the Type 1 channel access procedure is used for sidelink transmission in the set of channels C, access the first channel using the Type 1 channel access procedure, and perform transmission in the second channel using the Type 2A channel access procedure immediately before the transmission in the first channel. Alternatively, the terminal device 1 may intend to perform sidelink transmission in the set of channels C, and when the Type 1 channel access procedure is used for sidelink transmission in the set of channels C, the channel frequencies of the set of channels C are a subset of the set of channel frequencies defined, access the first channel using the Type 1 channel access procedure, and perform transmission in the second channel using the Type 2A channel access procedure immediately before the transmission in the first channel, and perform transmission in the second channel using the Type 2A channel access procedure immediately before the transmission in the first channel. The first channel is a channel included in the set of channels C. The first channel is any channel included in the set of channels C, and may be randomly selected from the set of channels C. The second channel is a channel included in the set of channels C excluding the first channel. For example, in FIG. 11, the terminal device 1 may apply a multi-channel access procedure to perform sidelink transmission that starts simultaneously in RB set #0, RB set #1, and RB set #2 in slot #1. The terminal device 1 may randomly select a first channel from RB set #0, RB set #1, and RB set #2. The terminal device 1 may select RB set #1 as the first channel. RB set #0 and RB set #2 may be defined as the second channel. The terminal device 1 may perform Type 1 channel access procedure in RB set #1. When Type 1 channel access is successful in RB set #1, the terminal device 1 may perform transmission using Type 2A channel access procedure in the second channel immediately before transmission in the first channel. That is, the terminal device 1 may perform transmission using Type 2A channel access procedure in RB set #0 and RB set #2. If the terminal device 1 does not satisfy the conditions for performing the Type 2A channel access procedure on the second channel, the terminal device 1 may perform the Type 1 channel access procedure on each channel of the set C of channels.

When the terminal device 1 performs sidelink transmission on a channel using the Type 2A channel access procedure, the terminal device 1 may perform sensing with a sensing interval of at least 25 μs. If the channel is idle, the terminal device 1 may perform sidelink transmission on the channel immediately after sensing. Here, the 25 μs sensing interval may be composed of a first period and one sensing slot immediately following the first period. The first period may be of 16 μs duration. The first period may include one sensing slot at the start of the first period. One sensing slot may be of 9 μs duration. The terminal device 1 may consider the channel to be idle if both sensing slots of the 25 μs sensing interval are idle. For example, the terminal device 1 may define one sensing slot immediately following the first period as the first sensing slot. The terminal device 1 may define a sensing slot included in the start of the first period as the second sensing slot. If both the first sensing slot and the second sensing slot are idle, the terminal device 1 may determine that the channel is idle and perform transmission. In other words, the Type 2A channel access procedure may be a channel sensing method that senses the channel for at least 25 μs and transmits if the channel is idle. The Type 2A channel access procedure performed for sidelink transmission may be referred to as Type 2A SL channel access procedure. The Type 2A channel access procedure may be referred to as Type 2A LBT.

If the terminal device 1 cannot access any of the channels of the carrier bandwidth for which sidelink resources are scheduled or configured, the terminal device 1 cannot transmit on channel set C. For example, the terminal device 1 may execute a multi-channel access procedure to transmit 111 in FIG. 11. If the terminal device 1 fails to access any of the channels RB set #0, RB set #1, or RB set #2, it cannot transmit 111. If the terminal device 1 executes a multi-channel access procedure to transmit 111 and fails to access any of the channels RB set #0, RB set #1, or RB set #2, it cannot transmit even if it successfully accesses channels in other RB sets.

　After the multi-channel access procedure is successful for the set of channels C, the terminal device 1 may perform a second sidelink transmission after the first sidelink transmission within the channel occupancy initiated in the set of channels. The second sidelink transmission may be an S-SSB transmission. The second sidelink transmission may be a PSFCH transmission. The second sidelink transmission may be a PSCCH/PSSCH transmission. The second sidelink transmission may be a transmission including either an S-SSB or a PSFCH or a PSCCH/PSSCH.

FIG. 12 is a diagram showing multiple sidelink transmissions in multiple channels in consecutive slots of terminal device 1 according to one aspect of this embodiment. Terminal device 1 may include any of terminal devices 1A to 1D of FIG. 1. In FIG. 12, one horizontal square represents one slot. Slot #0 is a slot that belongs to the resource pool and has an index of 0. Slot #1 is a slot that belongs to the resource pool and has an index of 1. Slot #2 is a slot that belongs to the resource pool and has an index of 2. Slot #3 is a slot that belongs to the resource pool and has an index of 3. Slot #4 is a slot that belongs to the resource pool and has an index of 4. RB set #0 is an RB set that belongs to the resource pool and has an index of 0. RB set #1 is an RB set that belongs to the resource pool and has an index of 1. RB set #2 is an RB set that belongs to the resource pool and has an index of 2. 121 may be a sidelink transmission that starts simultaneously using RB set #0, RB set #1, and RB set #2. 121 may be a PSCCH/PSSCH transmission. 121 may be a PSSCH transmission. 121 may be a PSFCH transmission. 121 may be an S-SSB transmission. The terminal device 1 may perform a multi-channel access procedure for 121. 122 may be a sidelink transmission performed within a channel occupancy initiated for the transmission of 121. 122 may be a sidelink transmission using RB set#1 and RB set#2. 122 may be a PSCCH/PSSCH transmission. 122 may be a PSSCH transmission. 122 may be a PSFCH transmission. 122 may be an S-SSB transmission. RB set#0 may be referred to as channel#0. RB set#1 may be referred to as channel#1. RB set#2 may be referred to as channel#2. The terminal device 1 may transmit either PSCCH/PSSCH, PSFCH or S-SSB in each RB set 121. The terminal device 1 may transmit either PSCCH/PSSCH, PSFCH or S-SSB in each RB set 122. For example, the terminal device 1 may transmit PSFCH#0 in RB set#0, PSFCH#1 in RB set#1 and PSFCH#2 in RB set#2. The terminal device 1 may transmit PSCCH/PSSCH#0 in RB set#0, PSCCH/PSSCH#1 in RB set#1 and PSCCH/PSSCH#2 in RB set#2. The terminal device 1 may transmit PSCCH/PSSCH in RB set#0, PSFCH in RB set#1 and S-SSB in RB set#2.

In a first embodiment of the present invention, when the terminal device 1 applies a multi-channel access procedure to perform multiple sidelink transmissions in one or more consecutive slots on multiple channels, the terminal device 1 may select a maximum channel access priority class value among multiple channel access priority class values associated with the multiple sidelink transmissions and use the channel access priority class value selected in the multi-channel access procedure for the channel on which the Type 1 channel access procedure is performed. When the terminal device 1 performs a multi-channel access procedure to perform multiple sidelink transmissions on multiple channels in one or more consecutive slots in a shared spectrum and initiates channel occupancy, the terminal device 1 may determine a channel access priority class value to be used on the channel on which the Type 1 channel access procedure is performed from multiple channel access priority class values associated with the multiple sidelink transmissions. One channel access priority class value may be associated with each sidelink transmission. In this embodiment, when the terminal device 1 performs a multi-channel access procedure to perform multiple sidelink transmissions on multiple channels in one or more consecutive slots in the shared spectrum to initiate a channel occupancy, the terminal device 1 may select a maximum channel access priority class value from multiple channel access priority class values associated with the multiple sidelink transmissions. The terminal device 1 may use the selected channel access priority class value in the multi-channel access procedure on the channel on which the Type 1 channel access procedure is performed. The terminal device 1 may perform a multi-channel access procedure for a first sidelink transmission transmitting on the set C of channels. The terminal device 1 may perform a second sidelink transmission after the first sidelink transmission within the channel occupancy initiated on the set C of channels after the multi-channel access procedure is successful for the set C of channels. The first sidelink transmission and the second sidelink transmission may be multiple sidelink transmissions on multiple channels in one or more consecutive slots. When the terminal device 1 applies a multi-channel access procedure to perform a first sidelink transmission and a second sidelink transmission, the terminal device 1 may select a maximum channel access priority class value among a plurality of channel access priority class values associated with the first sidelink transmission and the second sidelink transmission. The terminal device 1 may use the selected channel access priority class value in the multi-channel access procedure on a channel on which a Type 1 channel access procedure is performed. The second sidelink transmission may be a transmission using one RB set. The terminal device 1 may perform a third sidelink transmission in the channel occupancy after the second sidelink transmission. In this case, the plurality of sidelink transmissions may include the first sidelink transmission, the second sidelink transmission, and the third sidelink transmission. The third sidelink transmission may be a transmission using one RB set. The channel on which the sidelink transmission associated with the maximum channel access priority class value is performed may be different from the channel on which the Type 1 channel access procedure is performed.

For example, in FIG. 12, 121 may be a first sidelink transmission performed using RB set#0, RB set#1, and RB set#2. The terminal device 1 may perform a multi-channel access procedure for RB set#0, RB set#1, and RB set#2. The channel set C may be composed of RB set#0, RB set#1, and RB set#2. The terminal device 1 may transmit 121 if the multi-channel access procedure is successful. The terminal device 1 may transmit 122 within the channel occupancy initiated for the transmission of 121. The transmissions of 121 and 122 may be multiple sidelink transmissions on multiple channels in multiple consecutive slots. The channel access priority class value of 121 may be 1. The channel access priority class value of 122 may be 3. When terminal device 1 performs a multi-channel access procedure to transmit 121 and 122, terminal device 1 may select the largest channel access priority class value among multiple channel access priority class values associated with 121 and 122. Since the channel access priority class value of 121 is 1 and the channel access priority class value of 122 is 3, terminal device 1 may select the channel access priority class value 3 of 122 which has the largest channel access priority class value. Terminal device 1 may use the channel access priority class value selected in the multi-channel access procedure performed in channel set C for transmitting 121 and 122 on the channel on which Type 1 channel access procedure is performed. Terminal device 1 may use the channel access priority class value 3 on the channel on which Type 1 channel access procedure is performed in the multi-channel access procedure. When the terminal device 1 performs Type 1 channel access on each channel of the channel set C in the multi-channel access procedure, the terminal device 1 may use the channel access priority class value 3 on each channel. In other words, when the terminal device 1 performs Type 1 channel access procedure on each channel of RB set #0, RB set #1, and RB set #2, the terminal device 1 may perform Type 1 channel access procedure using the channel access priority class value 3 on each channel of RB set #0, RB set #1, and RB set #2. When the terminal device 1 performs Type 1 channel access procedure on one channel of the channel set C in the multi-channel access procedure and Type 2A channel access procedure on the other channels, the terminal device 1 may use the channel access priority class value 3 on the channel on which the Type 1 channel access procedure is performed. When the terminal device 1 selects RB set #0 as the channel on which the Type 1 channel access procedure is performed, the terminal device 1 may use a channel access priority class value of 3 for the Type 1 channel access procedure on RB set #0. The terminal device 1 may perform a Type 2A channel access procedure on RB set #1 and RB set #2. 121 may be referred to as a first sidelink transmission. 122 may be referred to as a second sidelink transmission. When the terminal device 1 performs a Type 1 channel access procedure on one channel of the set C of channels in a multi-channel access procedure and a Type 2A channel access procedure on the other channels, the channel on which the Type 1 channel access procedure is performed may be referred to as a first channel. When terminal device 1 performs a Type 1 channel access procedure on one channel of channel set C and a Type 2A channel access procedure on the other channels in a multi-channel access procedure, the channel on which the Type 2A channel access procedure is performed may be referred to as the second channel. RB set#0 may be referred to as channel#0. RB set#1 may be referred to as channel#1. RB set#2 may be referred to as channel#2.

The channel on which the sidelink transmission associated with the maximum channel access priority class value is performed may be different from the channel on which the Type 1 channel access procedure is performed. For example, in FIG. 12, the channel access priority class value of 121 may be 1. The channel access priority class value of 122 may be 3. The transmission of 122 may be associated with the maximum channel access priority class value. RB set#1 and RB set#2 may be the channels on which the sidelink transmission associated with the maximum channel access priority class value is performed. When the terminal device 1 performs a Type 1 channel access procedure with RB set#0 in the multi-channel access procedure, the terminal device 1 may use a channel access priority class value of 3.

FIG. 13 is a diagram showing an example of processing of a multi-channel access procedure for performing multiple sidelink transmissions on multiple channels in one or more consecutive slots of a terminal device 1 according to one aspect of this embodiment. The terminal device 1 initiates a multi-channel access procedure for performing multiple sidelink transmissions on multiple channels in one or more consecutive slots (S131). The terminal device 1 selects the largest channel access priority class value among the channel access priority class values associated with the multiple sidelink transmissions (S132). The terminal device 1 applies the selected channel access priority class value to the channel on which the Type 1 channel access procedure is performed (S133).

As described above, in an embodiment of the present invention, when the terminal device 1 applies a multi-channel access procedure to perform multiple sidelink transmissions on multiple channels in one or more consecutive slots, the terminal device 1 may select the largest channel access priority class value among multiple channel access priority class values associated with the multiple sidelink transmissions, and use the selected channel access priority class value on the channel on which the Type 1 channel access procedure is performed in the multi-channel access procedure. With this invention, when the multi-channel access procedure is applied to perform multiple sidelink transmissions on multiple channels in one or more consecutive slots, the channel access priority class value to be used on the channel on which the Type 1 channel access procedure is performed in the multi-channel access procedure can be selected fairly.

In a second embodiment according to the present invention, when the terminal device 1 performs a multi-channel access procedure for multiple sidelink transmissions on multiple channels in one or more consecutive slots and performs a Type 1 channel access procedure on one channel and a Type 2A channel access procedure on another channel, the terminal device 1 may perform the Type 1 channel access procedure on the channel on which the sidelink transmission is performed, which is associated with a maximum channel access priority class value among multiple channel access priority class values related to the multiple sidelink transmissions. When the terminal device 1 performs a multi-channel access procedure for multiple sidelink transmissions on multiple channels in one or more consecutive slots in a shared spectrum and performs a Type 1 channel access procedure on one channel and a Type 2A channel access procedure on another channel to start channel occupancy, the terminal device 1 may perform the Type 1 channel access procedure on the channel on which the sidelink transmission is performed, which is associated with a maximum channel access priority class value among multiple channel access priority class values related to the multiple sidelink transmissions. One channel access priority class value may be associated with each sidelink transmission. The terminal device 1 may perform a multi-channel access procedure for a first sidelink transmission in the set of channels C. After the multi-channel access procedure has been successful for the set of channels C, the terminal device 1 may perform a second sidelink transmission after the first sidelink transmission within the channel occupancy initiated in the set of channels C. Here, the multi-channel access procedure may be a method of performing a Type 1 channel access procedure in some channels of the set of channels C and a Type 2A channel access procedure in other channels. The first sidelink transmission and the second sidelink transmission may be multiple sidelink transmissions in multiple channels in one or more consecutive slots. When the terminal device 1 applies the multi-channel access procedure for the first sidelink transmission and the second sidelink transmission, the terminal device 1 may select a maximum channel access priority class value among multiple channel access priority class values associated with the first sidelink transmission and the second sidelink transmission. The terminal device 1 may perform a Type 1 channel access procedure in a channel in which the sidelink transmission is performed and to which the selected channel access priority class value is associated. When the channel access priority class value of the first sidelink transmission is the largest, the terminal device 1 may perform Type 1 channel access procedure on the channel on which the first sidelink transmission is performed. When the channel access priority class value of the second sidelink transmission is the largest, the terminal device 1 may perform Type 1 channel access procedure on the channel on which the second sidelink transmission is performed. The second sidelink transmission may be a transmission using one RB set. The terminal device 1 may perform a third sidelink transmission within the channel occupancy after the second sidelink transmission. In this case, the multiple sidelink transmissions may include the first sidelink transmission, the second sidelink transmission, and the third sidelink transmission. The third sidelink transmission may be a transmission using one RB set.

For example, in FIG. 12, 121 may be a first sidelink transmission performed using RB set#0, RB set#1, and RB set#2. The terminal device 1 may perform a multi-channel access procedure for RB set#0, RB set#1, and RB set#2. The channel set C may be composed of RB set#0, RB set#1, and RB set#2. The terminal device 1 may transmit 121 if the multi-channel access procedure is successful. The terminal device 1 may transmit 122 within the channel occupancy initiated for the transmission of 121. The transmissions of 121 and 122 may be multiple sidelink transmissions on multiple channels in multiple consecutive slots. The channel access priority class value of 121 may be 1. The channel access priority class value of 122 may be 3. When the terminal device 1 executes a multi-channel access procedure to transmit 121 and 122, the terminal device 1 may select the maximum channel access priority class value among the multiple channel access priority class values associated with 121 and 122. Here, since the channel access priority class value of 121 is 1 and the channel access priority class value of 122 is 3, the terminal device 1 may select the channel access priority class value 3 of 122, which has the maximum channel access priority class value. When the terminal device 1 executes a multi-channel access procedure to perform multiple sidelink transmissions on multiple channels in one or more consecutive slots, and executes a Type 1 channel access procedure on one channel and a Type 2A channel access procedure on another channel, the terminal device 1 may execute a Type 1 channel access procedure on the channel on which the transmission of 122 is performed. That is, the terminal device 1 may execute a Type 1 channel access procedure on either the channel of RB set#1 or RB set#2. When the terminal device 1 performs a Type 1 channel access procedure on RB set #2, it may perform a Type 2A channel access procedure on RB set #0 and RB set #1. 121 may be referred to as a first sidelink transmission. 122 may be referred to as a second sidelink transmission. When the terminal device 1 performs a Type 1 channel access procedure on one channel of a set of channels C in a multi-channel access procedure and a Type 2A channel access procedure on another channel, the channel on which the Type 1 channel access procedure is performed may be referred to as a first channel. When the terminal device 1 performs a Type 1 channel access procedure on one channel of a set of channels C in a multi-channel access procedure and a Type 2A channel access procedure on another channel, the channel on which the Type 2A channel access procedure is performed may be referred to as a second channel. RB set #0 may be referred to as channel #0. RB set#1 may be referred to as channel#1. RB set#2 may be referred to as channel#2.

Each sidelink transmission of the multiple sidelink transmissions may be any of PSCCH/PSSCH, PSSCH, PSFCH, or S-SSB. The multiple sidelink transmissions may be MCSt transmissions of multiple TBs. The first sidelink transmission may be a first sidelink transmission among the multiple sidelink transmissions. The second sidelink transmission may be a next sidelink transmission after the first sidelink transmission among the multiple sidelink transmissions. The first sidelink transmission may be a transmission using one RB set. The second sidelink transmission may be a transmission using one RB set. The RB sets used for the first sidelink transmission and the second sidelink transmission may be different. If the RB sets used for the first sidelink transmission and the second sidelink transmission are different, the terminal device 1 may perform a multi-channel access procedure for all RB sets used for the first sidelink transmission and the second sidelink transmission. For example, if the terminal device 1 uses RB set#0 and RB set#1 for a first sidelink transmission and RB set#1 and RB set#2 for a second sidelink transmission, the terminal device 1 may perform a multi-channel access procedure for RB set#0, RB set#1, and RB set#2. If the terminal device 1 uses RB set#0 and RB set#1 for a first sidelink transmission and RB set#2 for a second sidelink transmission, the terminal device 1 may perform a multi-channel access procedure for RB set#0, RB set#1, and RB set#2. If the terminal device 1 uses RB set#0 for a first sidelink transmission and RB set#1 for a second sidelink transmission, the terminal device 1 may perform a multi-channel access procedure for RB set#0 and RB set#1.

As described above, in an embodiment of the present invention, when the terminal device 1 performs a multi-channel access procedure to perform multiple sidelink transmissions on multiple channels in one or more consecutive slots, and performs a Type 1 channel access procedure on one channel and a Type 2A channel access procedure on another channel, the terminal device 1 may perform a Type 1 channel access procedure on a channel on which a sidelink transmission is performed that is associated with a maximum channel access priority class value among multiple channel access priority class values related to the multiple sidelink transmissions. According to this invention, when a multi-channel access procedure is applied to perform multiple sidelink transmissions on multiple channels in one or more consecutive slots, the channel access priority class value to be used on the channel on which the Type 1 channel access procedure is performed in the multi-channel access procedure can be fairly selected.

When applying a multi-channel access procedure to perform multiple sidelink transmissions on multiple channels in one or more consecutive slots, the terminal device 1 includes a control unit that selects the largest channel access priority class value among multiple channel access priority class values associated with the multiple sidelink transmissions, and a transmission unit that uses the selected channel access priority class value on a channel on which a Type 1 channel access procedure is performed in the multi-channel access procedure and transmits multiple sidelink transmissions on multiple channels in one or more consecutive slots.

This embodiment may be performed in an unlicensed band where channel sensing is performed. The unlicensed band may be referred to as a shared spectrum. The unlicensed band may be referred to as an unlicensed spectrum.

The programs operating in the base station device 3 and terminal device 1 relating to one aspect of the present invention may be programs (programs that cause a computer to function) that control a CPU (Central Processing Unit) or the like so as to realize the functions of the above-mentioned embodiment of the present invention. Information handled by these devices is temporarily stored in RAM (Random Access Memory) during processing, and is then stored in various ROMs such as Flash ROM (Read Only Memory) or HDD (Hard Disk Drive), and is read, modified, and written by the CPU as necessary.

In addition, a part of the terminal device 1 and the base station device 3 in the above-mentioned embodiment may be realized by a computer. In that case, a program for realizing this control function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read into a computer system and executed to realize the control function.

The "computer system" here refers to a computer system built into the terminal device 1 or base station device 3, and includes hardware such as an OS and peripheral devices. Also, the "computer-readable recording medium" refers to portable media such as flexible disks, optical magnetic disks, ROMs, and CD-ROMs, and storage devices such as hard disks built into the computer system.

Furthermore, "computer-readable recording medium" may include something that dynamically holds 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 holds 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 a case. 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.

The terminal device 1 may be composed of at least one processor and at least one memory including computer program instructions (computer program). The memory and computer program instructions (computer program) may be configured to cause the terminal device 1 to perform the operations and processes described in the above embodiments using the processor. The base station device 3 may be composed of at least one processor and at least one memory including computer program instructions (computer program). The memory and computer program instructions (computer program) may be configured to cause the base station device 3 to perform the operations and processes described in the above embodiments using the processor.

The base station device 3 in the above-described embodiment can also be realized as a collection (device group) consisting of multiple devices. Each of the devices constituting the device group may have some or all of the functions or functional blocks of the base station device 3 related to the above-described embodiment. It is sufficient for the device group to have all of the functions or functional blocks of the base station device 3. The terminal device 1 related to the above-described embodiment can also communicate with the base station device as a collection.

Furthermore, the base station device 3 in the above-mentioned embodiments may be EUTRAN (Evolved Universal Terrestrial Radio Access Network) and/or NG-RAN (NextGen RAN, NR RAN).Furthermore, the base station device 3 in the above-mentioned embodiments may have some or all of the functions of an upper node for eNodeB and/or gNB.

Furthermore, some or all of the terminal device 1 and base station device 3 in the above-described embodiment may be realized as an LSI, which is typically an integrated circuit, or may be realized as a chipset.
Each functional block of the terminal device 1 and the base station device 3 may be individually formed into a chip, or may be partially or entirely integrated into a chip. The integrated circuit method is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. In addition, if an integrated circuit technology that can replace LSI appears due to the advancement of semiconductor technology, it is also possible to use an integrated circuit based on that technology.

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

Although the embodiments of the present invention have 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 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 similar effects.

Possible industrial applications

One aspect of the present invention can be used, for example, in a communication system, a communication device (e.g., a mobile phone device, a base station device, a wireless LAN device, or a sensor device), an integrated circuit (e.g., a communication chip), or a program, etc.

Claims (3)

A terminal device comprising a processor and a memory for storing computer program code,
applying a multi-channel access procedure for multiple sidelink transmissions on multiple channels in one or more consecutive slots;
selecting a highest channel access priority class value among a plurality of channel access priority class values associated with the plurality of sidelink transmissions;
using the channel access priority class value selected in the multi-channel access procedure in a channel in which a Type 1 channel access procedure is performed;
A terminal device that performs operations including: a channel on which the sidelink transmission associated with the maximum channel access priority class value is performed is different from a channel on which the Type 1 channel access procedure is performed;
The terminal device according to claim 1 , A communication method for use in a terminal device, comprising:
applying a multi-channel access procedure for multiple sidelink transmissions on multiple channels in one or more consecutive slots;
selecting a highest channel access priority class value among a plurality of channel access priority class values associated with the plurality of sidelink transmissions;
using the channel access priority class value selected in the multi-channel access procedure on a channel in which a Type 1 channel access procedure is performed;
A communication method including:

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