WO2026011889A1 - Communication method and apparatus - Google Patents

Abstract

The present application discloses a communication method and apparatus. The method comprises: sending first data to a terminal device; receiving a first HARQ codebook from the terminal device, wherein the first HARQ codebook comprises first HARQ feedback information corresponding to the first data; and when a first resource comprises a second resource and the first HARQ feedback information is NACK, sending second data to the terminal device, wherein the first resource comprises a resource in which the probability of an uplink and downlink transmission conflict in the terminal device is greater than zero, the second resource is a resource used by the terminal device to receive the first data, and the second data is data that can be independently decoded after the first data has been retransmitted. In the present application, when the reason for the first HARQ feedback information being NACK may be the presence of an uplink and downlink transmission conflict in the terminal device, a network device can send, to the terminal device, the second data that can be independently decoded, so that the terminal device does not rely on the first data, thereby improving data transmission efficiency.

Description

A communication method and apparatus

Cross-references to related applications

This application claims priority to Chinese Patent Application No. 202410920658.8, filed on July 10, 2024, entitled "A Communication Method and Apparatus"; and to Chinese Patent Application No. 202411497033.1, filed on October 24, 2024, entitled "A Communication Method and Apparatus", the entire contents of which are incorporated herein by reference.

Technical Field

This application relates to the field of communication technology, and in particular to a communication method and apparatus.

Background Technology

Data transmission reliability is a crucial performance indicator in communication systems. In a communication system, network devices send data to terminal devices via the Physical Downlink Shared Channel (PDSCH). Upon receiving the data, the terminal device sends a Hybrid Automatic Repeat Request (HARQ) feedback message to the network device via the Physical Uplink Shared Channel (PUSCH) or the Physical Uplink Control Channel (PUCCH). The network device determines whether the data transmission was successful based on whether the HARQ feedback from the terminal device is an acknowledgment (ACK) or a negative acknowledgment (NACK), thereby improving data transmission reliability.

Currently, there are various reasons why a network device might send data to a terminal device, but the terminal device might respond with a NACK. For example, the terminal device might fail to decode the data sent by the network device, or the terminal device might experience uplink/downlink transmission conflicts, resulting in it not receiving the data sent by the network device. In high-latency communication scenarios (such as non-terrestrial network (NTN) communication scenarios), the actual uplink/downlink transmission conflicts of the terminal device may not align with the uplink/downlink transmission conflicts perceived by the network device. Therefore, when the terminal device responds with a NACK, the network device may not be able to determine the specific reason for the NACK, leading to low data transmission efficiency.

Summary of the Invention

This application provides a communication method and apparatus to improve data transmission efficiency.

In a first aspect, embodiments of this application provide a communication method that can be applied to a network device or a component (e.g., a unit/module, circuit, or chip) within the network device. The method includes: the network device sending first data to a terminal device; the network device receiving a first Hybrid Automatic Repeat Request (HARQ) codebook from the terminal device, wherein the first HARQ codebook includes first HARQ feedback information corresponding to the first data; and, when a first resource includes a second resource and the first HARQ feedback information is a Negative Acknowledgment (NACK), the network device sending second data to the terminal device, wherein the first resource includes resources where the probability of uplink/downlink transmission conflicts on the terminal device is greater than zero, the second resource is a resource used by the terminal device to receive the first data, and the second data is data that can be independently decoded by the terminal device after the network device performs retransmission processing on the first data.

In this embodiment, the network device can determine whether the resource from which the terminal device receives the first data is a resource that may have uplink or downlink transmission conflicts, and determine the specific reason why the first HARQ feedback information corresponding to the first data is NACK. If it is determined that the specific reason why the first HARQ feedback information corresponding to the first data is NACK may be that the terminal device has uplink or downlink transmission conflicts, the network device can send second data that can be independently decoded by the terminal device, so that the terminal device can independently decode the second data without relying on the first data, thereby improving data transmission efficiency.

In one possible implementation, when the first resource includes the second resource, the first HARQ feedback information corresponds to two bits on the first HARQ codebook.

In this embodiment, the terminal device and the network device can pre-determine the number of bits occupied by the first HARQ feedback information on the first HARQ codebook, depending on whether the first resource includes the second resource. For example, when the first resource includes the second resource, the first HARQ feedback information corresponds to two bits on the first HARQ codebook to distinguish between NACK feedback caused by unsuccessful decoding of the first data and NACK feedback caused by not receiving the first data. Alternatively, when the first resource does not include the second resource, the first HARQ feedback information corresponds to only one bit on the first HARQ codebook to reduce signaling overhead.

In one possible implementation, the method further includes: when the values of the two bits are first values, the network device determines that the first HARQ feedback information is NACK, and that the terminal device has uplink and downlink transmission conflicts on the second resource.

[Corrected according to Rule 91, 2025]
In this embodiment, the network device can determine whether the first HARQ feedback information being ACK is due to unsuccessful decoding of the first data or failure to receive the first data, based on the specific values of the two bits in the first HARQ codebook, thereby improving the accuracy of the determination.

In one possible implementation, when the first resource includes the second resource and the first HARQ feedback information is a negative acknowledgment (NACK), the network device sends the second data to the terminal device, including: when the first resource includes the second resource, the first HARQ feedback information is NACK, and the terminal device has uplink and downlink transmission conflicts on the second resource, the network device sends the second data to the terminal device.

In this embodiment, when the network device determines that the specific reason for the first HARQ feedback information corresponding to the first data being NACK must be that there is an uplink and downlink transmission conflict in the terminal device, it then sends the second data that can be independently decoded by the terminal device, so that the terminal device can independently decode the second data without relying on the first data, thereby improving data transmission efficiency.

In one possible implementation, the first HARQ codebook is a semi-static codebook. The first HARQ codebook also includes second HARQ feedback information, which corresponds to a third resource. The third resource is a resource used by the terminal device to receive third data. The third data is not data sent by the network device to the terminal device. The second HARQ feedback information corresponds to a bit in the first HARQ codebook.

In this embodiment, since the second HARQ feedback information is the HARQ feedback information corresponding to the transmission opportunity when there is a transmission opportunity but the network device does not actually transmit data during that transmission opportunity, the network device can determine the specific reason for the second HARQ feedback information to give NACK. Therefore, the second HARQ feedback information can correspond to only one bit on the first HARQ codebook to reduce signaling overhead.

In one possible implementation, the method includes: the network device sending a first reference signal and a second reference signal to the terminal device, wherein the first reference signal has a lower priority than the second reference signal; the network device receiving first channel state information (CSI) from the terminal device, wherein the first CSI and the first HARQ codebook are carried in the same physical uplink control channel (PUCCH), and the first CSI corresponds to the first reference signal; and the network device determining that the terminal device has an uplink/downlink transmission conflict on a fourth resource, wherein the fourth resource is a resource used by the terminal device to receive the second reference signal.

In this implementation, the priority of the first CSI corresponding to the first reference signal is lower than the priority of the second CSI corresponding to the second reference signal. The terminal device should send the first HARQ codebook and the second CSI to the network device via the same PUCCH. However, due to uplink and downlink transmission conflicts on the fourth resource, the terminal device did not receive the second reference signal on the fourth resource, meaning the second CSI is invalid. Therefore, the terminal device sends the first HARQ codebook and the first CSI to the network device via the same PUCCH to increase the amount of effective information in the CSI feedback and reduce resource waste.

Secondly, embodiments of this application also provide a communication method, which can be applied to a terminal device or a component (e.g., a unit/module, circuit, or chip) in the terminal device. The method includes: the terminal device sending a first Hybrid Automatic Repeat Request (HARQ) codebook to a network device, wherein the first HARQ codebook includes first HARQ feedback information, and the first HARQ feedback information corresponds to first data sent by the network device to the terminal device; and, in the case that the first resource includes a second resource and the first HARQ feedback information is a negative acknowledgment (NACK), the terminal device receiving second data from the network device, wherein the first resource includes resources in which the probability of uplink/downlink transmission conflict of the terminal device is greater than zero, the second resource is a resource used by the terminal device to receive the first data, and the second data is data that can be independently decoded by the terminal device after the network device performs retransmission processing on the first data.

In one possible implementation, when the first resource includes the second resource, the first HARQ feedback information corresponds to two bits on the first HARQ codebook.

In one possible implementation, the method further includes: when there is an uplink/downlink transmission conflict on the second resource, the terminal device determines that the two bits are a first value, the first value being used to indicate that the first HARQ feedback information is NACK.

In one possible implementation, when the first resource includes the second resource and the first HARQ feedback information is NACK, the terminal device receives the second data from the network device, including: when the first resource includes the second resource, the first HARQ feedback information is NACK, and the terminal device has uplink and downlink transmission conflicts on the second resource, the terminal device receives the second data from the network device.

In one possible implementation, the first HARQ codebook is a semi-static codebook. The first HARQ codebook also includes second HARQ feedback information, which corresponds to a third resource. The third resource is a resource used by the terminal device to receive third data. The third data is not data sent by the network device to the terminal device. The second HARQ feedback information corresponds to a bit in the first HARQ codebook.

In one possible implementation, the method includes: the terminal device receiving a first reference signal from the network device; and, in the event of an uplink/downlink transmission conflict on a fourth resource, the terminal device sending a first CSI to the network device, wherein the first CSI and the first HARQ codebook are carried in the same PUCCH, the first CSI corresponds to the first reference signal, and the fourth resource is a resource for the terminal device to receive a second reference signal, wherein the priority of the first reference signal is lower than the priority of the second reference signal.

The beneficial effects of the second aspect and its implementation can be referred to the beneficial effects of the first aspect and any of its implementations.

Thirdly, embodiments of this application provide a communication device, including a processor and a memory; the memory is used to store computer instructions, and when the device is running, the processor executes the computer instructions stored in the memory to cause the device to perform any implementation method of the first or second aspect described above. The memory may be volatile or non-volatile memory, such as a cache in a semiconductor chip.

Fourthly, embodiments of this application provide a communication device, which may be a network device or a terminal device, or a chip for a network device or a terminal device. The device has the function of implementing any of the methods described in the first or second aspect above. This function can be implemented in hardware or by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above-described functions.

Fifthly, embodiments of this application provide a communication device including units or means for performing the steps of any of the implementation methods in the first or second aspect described above.

Sixthly, embodiments of this application provide a communication device, including a processor and an interface circuit. The processor is used to communicate with other devices through the interface circuit and to execute any implementation method of the first or second aspect described above. The processor may be one or more processors.

In a seventh aspect, embodiments of this application provide a communication device including a processor coupled to a memory, the processor being configured to invoke a program stored in the memory to execute any implementation method of the first or second aspect described above. The memory may be located within or outside the device. The processor may also be one or more processors.

Eighthly, embodiments of this application also provide a computer-readable storage medium storing instructions that, when executed on a communication device, cause any implementation of the first or second aspect described above to be performed.

Ninthly, embodiments of this application also provide a computer program product, which includes a computer program or instructions that, when executed by a communication device, cause any implementation method in the first or second aspect described above to be performed.

In a tenth aspect, embodiments of this application also provide a chip system, including: a processor for executing any implementation method of the first aspect, or the second aspect, or the third aspect described above.

Eleventhly, embodiments of this application also provide a communication system, the system comprising: a network device for executing any implementation method executed by the network device in the first aspect; and a terminal device for executing any implementation method executed by the terminal device in the second aspect.

Attached Figure Description

Figure 1 is a schematic diagram of a communication system provided in an embodiment of this application;

Figure 2 is a schematic diagram of an NTN communication system provided in an embodiment of this application;

Figure 3 is a schematic diagram of a 5G satellite communication system provided in an embodiment of this application;

Figure 4 is a schematic diagram of HARQ feedback information transmitted in the same uplink time slot according to an embodiment of this application;

Figure 5 is a schematic diagram of a HARQ semi-static codebook provided in an embodiment of this application;

Figure 6 is a schematic diagram of a HARQ dynamic codebook provided in an embodiment of this application;

Figure 7 is a flowchart illustrating a communication method provided in an embodiment of this application;

Figure 8 is a schematic diagram of a first HARQ codebook provided in an embodiment of this application;

Figure 9 is a schematic diagram of another first HARQ codebook provided in an embodiment of this application;

Figure 10 is a schematic diagram of a communication device provided in an embodiment of this application;

Figure 11 is a schematic diagram of another communication device provided in an embodiment of this application.

Detailed Implementation

To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the embodiments of this application will be further described in detail below with reference to the accompanying drawings.

The communication method provided in this application can be applied to fourth-generation (4G) communication systems, such as Long Term Evolution (LTE), and also to fifth-generation (5G) communication systems, such as 5G New Radio (NR). It can also be applied to various future-evolving communication systems, such as future communication systems or integrated air-space-sea-terrestrial communication systems. The method provided in this application can be applied to terrestrial network communication systems or to non-terrestrial networks (NTN) communication systems. NTN communication systems can be satellite communication systems or other communication systems; this application does not limit the specific type of system used.

Figure 1 is a schematic diagram of a communication system provided in an embodiment of this application. As shown in Figure 1, the communication system 100 includes a network device 101 and a terminal device 102.

First, we will introduce the possible implementation forms and functions of network device 101 and terminal device 102 with examples.

Network device 101 provides services to terminal devices 102 within its coverage area. For example, referring to Figure 1, network device 101 provides wireless access to one or more terminal devices 102 within its coverage area.

Network device 101 is a node in a radio access network (RAN), also known as a base station or RAN node (or device). Examples of network devices 101 include: next-generation node B (gNB), next-generation evolved node B (Ng-eNB), transmission reception point (TRP), evolved Node B (eNB), radio network controller (RNC), node B (NB), base station controller (BSC), base transceiver station (BTS), home base station (e.g., home evolved Node B, or home Node B (HNB)), base band unit (BBU), or wireless fidelity (Wi-Fi) access point (AP). Network device 101 can also be a module or unit that performs some of the functions of a base station. For example, it can be a central unit (CU) or a distributed unit (DU). Here, the CU performs the functions of the base station's Radio Resource Control Protocol (RRC) and Packet Data Convergence Protocol (PDCP), and can also perform the functions of the Service Data Adaptation Protocol (SDAP). The DU performs the functions of the base station's Radio Link Control (RANC) and Medium Access Control (MAC) layers, and can also perform some or all of the physical layer functions. For specific descriptions of the above protocol layers, please refer to the relevant technical specifications of the 3rd Generation Partnership Project (3GPP). Network device 101 can also be a satellite, which can also be called a high-altitude platform, high-altitude aircraft, or satellite base station. Network device 101 can also be other devices with network device functions. For example, network device 101 can also be a device that performs network device functions in device-to-device (D2D) communication, vehicle-to-everything (V2X) communication, or machine-to-machine (M2M) communication. Network device 101 can also be any possible network device in future communication systems. In the embodiments of this application, the functions of network device 101 can also be executed by modules (such as chips) in the network device, or by a control subsystem containing network device functions. The control subsystem containing network device functions can be a control center in application scenarios such as smart grids, industrial control, intelligent transportation, and smart cities.

Terminal equipment 102, also known as user equipment (UE), mobile station (MS), mobile terminal (MT), etc., is a device that provides voice and/or data connectivity to a user. For example, terminal equipment 102 includes handheld devices with wireless connectivity, vehicle-mounted devices, etc. Currently, terminal device 102 can be: mobile phone, tablet computer, laptop computer, handheld computer, mobile internet device (MID), wearable device (such as smartwatch, smart bracelet, pedometer, etc.), vehicle-mounted device (such as car, bicycle, electric vehicle, airplane, ship, train, high-speed rail, etc.), virtual reality (VR) device, augmented reality (AR) device, wireless terminal in industrial control, smart home device (such as refrigerator, television, air conditioner, electricity meter, etc.), smart robot, workshop equipment, wireless terminal in self-driving, wireless terminal in remote medical surgery, wireless terminal in smart grid, wireless terminal in transportation safety, wireless terminal in smart city, or wireless terminal in smart home, flying device (such as smart robot, hot air balloon, drone, airplane), etc. Terminal device 102 can also be other devices with terminal device functions. For example, terminal device 102 can also be a device that performs terminal device functions in device-to-device (D2D) communication, vehicle-to-everything (V2X) communication, or machine-to-machine (M2M) communication. In particular, when communicating between network devices, the network device that performs terminal device functions can also be regarded as a terminal device. The method provided in this application embodiment can be executed by a terminal device or by a component of the terminal device (e.g., a processor, chip, or chip system). The subject executing the method of this application embodiment can also be called a communication device, which can be a terminal device or a component of the terminal device (e.g., a processor, chip, or chip system).

Based on the description of the communication system architecture shown in Figure 1, the method provided in this application embodiment can also be applied to NTN communication systems. In this application embodiment, the NTN communication system is taken as an example of a satellite communication system.

[Corrected according to Rule 91, 2025]
Figure 2 is a schematic diagram of an NTN communication system provided in an embodiment of this application. As shown in Figure 2, the NTN communication system includes a satellite 201 and a terminal device 202. The explanation of the terminal device 202 can refer to the relevant description of the terminal device 102 above. The satellite 201 can also be called a high-altitude platform, a high-altitude aircraft, or a satellite base station. Considering the NTN communication system in relation to a terrestrial network communication system, the satellite 201 can be viewed as one or more network devices in the terrestrial network communication system architecture. The satellite 201 provides communication services to the terminal device 202, and the satellite 201 can also connect to core network equipment. The structure and functions of the satellite 201 can also refer to the description of the network device 101 above. The communication method between the satellite 201 and the terminal device 202 can also refer to the description in Figure 1 above. Further details will not be repeated here.

Taking 5G as an example, Figure 3 is a schematic diagram of a 5G satellite communication system provided in an embodiment of this application. As shown in Figure 3, ground terminal equipment accesses the network through the 5G New Radio interface, and 5G base stations are deployed on satellites and connected to the 5G core network on the ground via wireless links. Simultaneously, wireless links exist between satellites to complete signaling interaction and user data transmission between 5G base stations. The devices and interfaces in Figure 3 are described below:

5G Core Network: Responsible for user access control, mobility management, session management, user security authentication, billing, and other services. It consists of multiple functional units, which can be divided into control plane and user plane functional entities. The control plane functional entities include: Access and Mobility Management Function (AMF), responsible for user access management, security authentication, and mobility management; and Session Management Function (SMF), responsible for user session management, allocating and releasing resources for user sessions. The user plane functional entities include: User Plane Function (UPF), responsible for managing user plane data transmission and traffic statistics.

Ground station: Responsible for forwarding signaling and service data between the 5G base station on the satellite and the 5G core network.

5G New Radio: The wireless link between a terminal and a 5G base station.

Xn interface: The interface between 5G base stations, mainly used for signaling interactions such as handover.

NG interface: The interface between 5G base stations and 5G core networks, mainly used for the exchange of non-access-stratum (NAS) signaling of the core network and user service data.

In this embodiment, network devices in the terrestrial network communication system and satellites in the NTN communication system are collectively considered as network devices. The apparatus used to implement the functions of the network device can be a network device itself; it can also be an apparatus capable of supporting the network device in implementing that function, such as a chip system, which can be installed within the network device. It is understood that when the method provided in this embodiment is applied to the NTN communication system, the actions performed by the network device can be applied to the satellite for execution.

In this application embodiment, the device for implementing the functions of the terminal device can be the terminal device itself; it can also be a device capable of supporting the terminal device in implementing the functions, such as a chip system, which can be installed in the terminal device. In this application embodiment, the chip system can be composed of chips, or it can include chips and other discrete devices. In the technical solutions provided in this application embodiment, the terminal device is used as an example to describe the technical solutions provided in this application embodiment.

In this embodiment of the application, both terminal devices and network devices can be referred to as communication devices. Terminal device 102 in FIG1 and terminal device 202 in FIG2 can be referred to as communication devices with terminal device functions, and network device 101 in FIG1 and satellite 201 in FIG2 can be referred to as communication devices with network device functions.

The communication system applicable to the embodiments of this application has been briefly introduced above. The relevant technical solutions involved in the embodiments of this application are described below.

(1) Hybrid Automatic Repeat Request Acknowledgment (HARQ) process

HARQ is a method to improve data transmission reliability. HARQ stores erroneously decoded data packets in a HARQ buffer. Upon receiving a retransmitted data packet, it merges the erroneously decoded packet with the retransmitted packet, resulting in a more reliable data packet than if decoded individually. This merging process is called soft merging. The merged data packet is then decoded; if decoding still fails, a retransmission is requested, and soft merging is repeated until successful decoding.

HARQ uses a cyclic redundancy check (CRC) to determine if a received data packet is corrupted, and the CRC check is performed after soft merging. If the CRC check is successful, the receiver sends an acknowledgment (ACK); if the CRC check fails, the receiver sends a negative acknowledgment (NACK).

HARQ can use a stop-and-wait protocol to send data. In a stop-and-wait process, the sender can send a transport block (TB) and then pause to wait for feedback. The receiver can use 1 bit of information to send an ACK or NACK response for that TB. However, the sender pausing after each transmission to wait for feedback results in low throughput. Therefore, HARQ can use multiple parallel stop-and-wait processes to send data; these parallel processes are also called HARQ processes. While waiting for feedback from one HARQ process, the sender can use another HARQ process to continue sending data, allowing for continuous data transmission. Each HARQ process requires an independent HARQ buffer at the receiver for soft merging of received data.

(2) HARQ codebook

Network devices send data to terminal devices via the physical downlink shared channel (PDSCH). After receiving the data, the terminal devices send HARQ feedback information to the network devices via the physical uplink shared channel (PUSCH) or the physical uplink control channel (PUCCH).

When sending HARQ feedback information, the terminal device can send one or more HARQ messages together in the same uplink time slot. In this embodiment, the combined HARQ feedback information is referred to as the HARQ codebook.

Figure 4 is a schematic diagram of HARQ feedback information transmitted on the same uplink time slot according to an embodiment of this application. As shown in Figure 4, it includes four downlink time slots (i.e., time slots n to n+3) and two uplink time slots (i.e., time slots n+2 to n+3). Each downlink time slot includes two PDSCHs (i.e., PDSCH1 to PDSCH4). Each uplink time slot includes one PUCCH (i.e., PUCCH1 to PUCCH2). The network device can transmit data #1 through PDSCH1 on time slot n, data #2 through PDSCH2 on time slot n+1, data #3 through PDSCH3 on time slot n+2, and data #4 through PDSCH4 on time slot n+3. The terminal device can transmit codebook #1 to the network device through PUCCH1 on time slot n+4 and codebook #2 to the network device through PUCCH2 on time slot n+5.

Specifically, codebook #1 carried on PUCCH1 includes HARQ feedback information corresponding to the data on PDSCH1 to PDSCH2, and codebook #2 carried on PUCCH2 includes HARQ feedback information corresponding to the data on PDSCH3 to PDSCH4. The HARQ codebook includes HARQ feedback information corresponding to the data on which PDSCHs is included, determined by a pre-configured set of time slots (i.e., the set of K values in Figure 4). For example, K=4 indicates that the HARQ feedback information corresponding to the data carried on the current channel will be transmitted in the fourth time slot after the current channel.

The HARQ codebooks mentioned above can be divided into two types: semi-static HARQ codebooks and dynamic HARQ codebooks. It should be understood that the type of HARQ codebook can be configured for the current cell via higher-layer signaling. For example, higher-layer signaling could be radio resource control (RRC).

A semi-static HARQ codebook refers to a codebook that provides feedback on all possible HARQ responses that could be transmitted in the current time slot. This codebook includes both the HARQ feedback information (feeding back the actual ACK or NACK) corresponding to data transmitted during a PDSCH transmission opportunity (when such an opportunity exists and data is actually transmitted), and the HARQ feedback information (feeding back NACK) corresponding to a PDSCH transmission opportunity that exists but data is not actually transmitted during that opportunity. Finally, the HARQ information from these two scenarios can be sorted according to the rules shown in Figure 4 to form the HARQ codebook.

Figure 5 is a schematic diagram of a HARQ semi-static codebook provided in an embodiment of this application. As shown in Figure 5, each carrier carries four time slots. The white positions indicate PDSCH transmission, and the shaded positions indicate no PDSCH transmission. According to the rules of the HARQ semi-static codebook described above, a total of 8 bits of HARQ codebook actually need to be fed back. The specific arrangement order is shown in Figure 5. The N in the shaded position indicates that the NACK corresponding to the PDSCH was not transmitted, and the A/N in the blank position indicates that the actual ACK or NACK corresponding to the PDSCH was transmitted.

[Corrected according to Rule 91, 2025]
The HARQ dynamic codebook refers to the HARQ information that is only fed back for data transmitted via PDSCH in the current time slot. This HARQ dynamic codebook includes the HARQ feedback information (feedback of the actual ACK or NACK) for the data when a PDSCH transmission opportunity exists and data is actually transmitted during that PDSCH transmission opportunity.

Figure 6 is a schematic diagram of a HARQ dynamic codebook provided in an embodiment of this application. As shown in Figure 6, each carrier carries four time slots. The white positions indicate PDSCH transmission, the slashed positions indicate no PDSCH transmission, and the grid shaded positions indicate that the network device sent a downlink control information (DCI) and scheduled the PDSCH transmission for this time slot. However, the terminal device did not receive this DCI, so the terminal device does not know that PDSCH was transmitted at this position, that is, there will be no corresponding HARQ information.

To address the issue of terminal devices missing DCIs, network devices add a counter downlink assignment index (C-DAI) and a total downlink assignment index (T-DAI) to the DCIs when scheduling PDSCHs. C-DAI indicates which DCI in the HARQ codebook the current DCI belongs to, and T-DAI indicates the total number of DCIs transmitted up to the current time slot. As shown in Figure 4, the two numbers in each position represent the values of (C-DAI and T-DAI). When a terminal device misses a DCI corresponding to a shaded grid position, the four received DCIs indicate (1,1), (2,3), (4,5), and (5,5), respectively. The terminal device can determine that a second DCI was missed based on the four C-DAI values (1,2,4,5); or it can determine that there should be another DCI indicating (3,3) at that moment based on the T-DAI value of 3 in the second time slot. Based on the two methods described above, the terminal device can supplement the HARQ information (NACK) at that position when feeding back the HARQ codebook.

(3) Redundancy version (RV)

If a network device sends data to a terminal device but the terminal device sends a NACK response, the network device needs to retransmit the data. Currently, the network device performs retransmission using cyclic redundancy, meaning it sends different redundant versions of the data to improve the decoding performance of the terminal device. If the terminal device fails to decode, in the next retransmission, it can combine the previously received redundant version with the currently received redundant version, thereby improving the decoding performance of the retransmission.

For some redundant data versions, the terminal device cannot decode them independently after receiving them; they need to be merged with the previously received redundant data versions before decoding. Therefore, this redundant data version can be transmitted in the second transmission or later. In the existing protocol, the order of transmitting different redundant data versions in the four transmissions is generally RV0, RV2, RV3, RV1. Among them, RV0 and RV3 are redundant data versions that can be decoded independently by the terminal device, meaning they do not need to be merged with the previously received redundant data versions before decoding. RV1 and RV2 are redundant data versions that cannot be decoded independently by the terminal device, meaning they need to be merged with the previously received redundant data versions before decoding.

(4) Uplink and downlink transmission conflicts

For terminal devices using time division duplex (TDD) (or half-duplex) communication, uplink and downlink transmissions cannot occur simultaneously. An interval of N _{_Tx-Rx} is required between uplink and downlink transmissions, and an interval of N _{_Rx-Tx} is required between downlink and uplink transmissions. The low-frequency band FR1 and high-frequency band FR2 are shown in Table 1.

Table 1: An example of the interval between uplink and downlink transmissions

In Table 1, 25600 and 13792 can represent the number of sampling points. Therefore, _NTx-Rx and _NTx-Tx are the number of sampling points multiplied by the sampling point interval. For example, in FR1, _NTx-Rx is the product of 25600 and the sampling point interval. It is understood that the sampling point interval can be predefined by the protocol, and this application does not impose specific limitations on it.

Therefore, when a half-duplex terminal device needs to perform uplink and downlink transmissions simultaneously, uplink and downlink transmission conflicts will occur. In other words, uplink and downlink transmission conflicts refer to conflicts that occur when uplink and downlink transmissions are performed simultaneously.

In terrestrial network communication scenarios, latency is relatively low, and the resources actually experiencing uplink/downlink transmission conflicts on the terminal device can be aligned with the resources perceived as experiencing uplink/downlink transmission conflicts by the network device. In NTN communication scenarios, latency is relatively high, and the resources actually experiencing uplink/downlink transmission conflicts on the terminal device cannot be aligned with the resources perceived as experiencing uplink/downlink transmission conflicts by the network device.

As can be seen, there are several reasons why a network device might send data to a terminal device, but the terminal device might send a NACK response. For example, the terminal device might fail to decode the data sent by the network device, the network device might not have sent any data, the terminal device might have missed a DCI (Distributed Access Control) check, resulting in not receiving the data from the network device, or there might be uplink/downlink transmission conflicts preventing the terminal device from receiving the data from the network device.

In high-latency communication scenarios (such as NTN communication scenarios), the actual uplink and downlink transmission conflicts of the terminal device may not align with the uplink and downlink transmission conflicts perceived by the network device. Therefore, when the terminal device sends a NACK, the network device may not be able to determine the specific reason for the NACK. Furthermore, the network device may not be able to select an appropriate redundant version of the data for retransmission, making it more likely that the terminal device will send another NACK for the retransmitted data, resulting in low data transmission efficiency.

Therefore, embodiments of this application provide a communication method for improving data transmission efficiency.

In the embodiments of this application, "when," "if," and "if" all refer to the device taking corresponding actions under certain objective circumstances, and are not time-limited, nor do they require the device to perform a judgment action, nor do they imply any other limitations. Unless otherwise specified, "if" and "if" can be substituted, and "when" and "in the case of" can be substituted. "When" and "if"/"if" can be substituted.

In the embodiments of this application, the terms "exemplary" or "for example" are used to indicate that something is an example, illustration, or description. Any embodiment or design that is described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the terms "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.

In this document, "used for indication" can include both direct and indirect indication. For example, when descriptive information I is used to indicate information J, it can mean that information I directly indicates information J or indirectly indicates information J, but it does not necessarily mean that information I carries information J.

Let information J, indicated by information I, be called the information to be indicated. In practice, there are many ways to indicate the information to be indicated, such as, but not limited to, directly indicating the information to be indicated, such as the information itself or its index. It can also be indirectly indicated by indicating other information, where there is a relationship between the other information and the information to be indicated. It can also indicate only a part of the information to be indicated, while the other parts are known or pre-agreed upon. For example, the indication of specific information can be achieved by using a pre-agreed (e.g., protocol-defined) order of various pieces of information, thereby reducing indication overhead to some extent. Simultaneously, common parts of various pieces of information can be identified and indicated uniformly to reduce the indication overhead caused by individually indicating the same information.

Furthermore, the specific instruction method can also be any existing instruction method, such as, but not limited to, the above-mentioned instruction methods and their various combinations. As described above, for example, when multiple pieces of information of the same type need to be indicated, the instruction methods for different pieces of information may differ. In specific implementation, the required instruction method can be selected according to specific needs. This application embodiment does not limit the selected instruction method. Therefore, the instruction methods involved in this application embodiment should be understood to cover various methods that enable the party to be instructed to obtain the information to be indicated.

In the embodiments of this application, "send" and "receive" indicate the direction of signal transmission. For example, "send information to XX" can be understood as the destination of the information being XX, which may include direct transmission via the air interface or indirect transmission via the air interface by other units or modules. "Receive information from YY" can be understood as the source of the information being YY, which may include direct reception from YY via the air interface or indirect reception from YY via the air interface by other units or modules. "Send" can also be understood as the "output" of the chip interface, and "receive" can also be understood as the "input" of the chip interface.

Information may undergo necessary processing, such as encoding and modulation, between the source and destination ends, but the destination end can understand the valid information from the source end. Similar statements in the embodiments of this application can be understood in a similar way, and will not be repeated here.

In this application embodiment, the number of nouns, unless otherwise specified, refers to "singular nouns or plural nouns," that is, "one or more." "At least one" means one or more, and "more than one" means two or more. "And/or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and/or B can mean: A exists alone, A and B exist simultaneously, or B exists alone, where A and B can be singular or plural. The character "/" can indicate that the related objects before and after are in an "or" relationship. For example, A/B means: A or B. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b, or c means: a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, and c can be single or multiple.

In this application, the ordinal numbers such as "first" and "second" are used to distinguish multiple objects, and are not used to limit the size, content, order, timing, priority, or importance of the multiple objects. For example, "first data" and "second data" refer to two different data, and do not indicate a difference in priority or importance between the two data. For a technical feature, the technical features within that technical feature are distinguished by "A," "B," "C," and "D," and there is no sequential or hierarchical order among the technical features described by "A," "B," "C," and "D." For example, in this document, "case A" and "case B" are only used to distinguish different content, and do not limit the sequential or hierarchical order, priority, or importance between cases A and B.

The solutions provided in the embodiments of this application are described in detail below with reference to the accompanying drawings. In the following description, the communication method provided in the embodiments of this application is used as an example applied to the communication systems shown in Figures 1-3. The communication systems and application scenarios described in the embodiments of this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided in the embodiments of this application. Those skilled in the art will understand that with the evolution of communication systems and the emergence of new application scenarios, the technical solutions provided in the embodiments of this application are also applicable to similar technical problems.

The following describes the communication method provided in this application, using an embodiment executed by a network device and a terminal device as an example. The steps executed by the network device can be implemented by the network device itself or by components within the network device (such as a baseband chip, or other processing units or processor modules). For example, the network device can be the network device shown in Figures 1-3, or it can be a chip (system) within the network device shown in Figures 1-3. The steps executed by the terminal device can be implemented by the terminal device itself or by components within the terminal device (such as a chip, processing unit, or processor module). The terminal device can be the terminal device shown in Figures 1-3, or it can be a chip (system) within the terminal device shown in Figures 1-3.

Figure 7 is a flowchart illustrating a communication method provided in an embodiment of this application. Figure 4 describes the method from the perspective of interaction between a network device and a terminal device. It should be understood that the embodiments of this application are only examples of execution through a network device and a terminal device, and are not limited to network devices and terminal devices. As shown in Figure 7, the communication method includes the following steps.

S701, The network device sends the first data to the terminal device.

In the embodiments of this application, the first data may be one or more TBs, or one or more code block groups (CBGs) in a TB. The embodiments of this application do not limit this.

The first data can be data that can be independently decoded by the terminal device, or it can be data that cannot be independently decoded by the terminal device; this application embodiment does not limit this. For example, when the first data is initial transmission data, the redundant version of the first data can be RV0, that is, it can be independently decoded by the terminal device; when the first data is retransmission data, the redundant version of the first data can be RV2, RV3, or RV1, that is, it can or cannot be independently decoded by the terminal device. For ease of explanation, this application embodiment takes the first data as initial transmission data as an example.

In practice, network devices can send first data to terminal devices via the first PDSCH. Network devices can also send a first DCI to terminal devices via the first PDCCH, which can be used to schedule the first data carried on the first PDSCH.

S702, The terminal device sends the first HARQ codebook to the network device, and the network device receives the first HARQ codebook from the terminal device.

In this embodiment, the first HARQ codebook may include first HARQ feedback information, which may correspond to first data. That is, the first HARQ feedback information is an ACK or NACK response from the terminal device to the first data.

It is understood that the terminal device may receive the first data from the network device through the first PDSCH, or the terminal device may not receive the first data from the network device through the first PDSCH. The terminal device's failure to receive the first data may be due to uplink/downlink transmission conflicts, or it may be due to the terminal device missing the first DCI. This application embodiment does not limit the specific cause of this failure. For ease of explanation, this application embodiment uses the example of the terminal device failing to receive the first data due to uplink/downlink transmission conflicts.

It is understandable that when the terminal device receives the first data and successfully decodes the first data, the first HARQ feedback information is ACK; when the terminal device receives the first data but fails to decode the first data, or when the terminal device does not receive the first data, the first HARQ feedback information is NACK.

In specific implementation, the terminal device can send the first HARQ codebook to the network device through the first PUCCH or the first PUSCH, and this application embodiment does not limit this. For ease of explanation, this application embodiment uses the first PUCCH as an example.

In one possible implementation, if the first HARQ feedback information is NACK, in order to avoid the network device being unable to determine whether the specific reason for the first HARQ feedback information being NACK is the failure to decode the first data or the failure to receive the first data, the terminal device can agree with the network device in advance on the number of bits occupied by the first HARQ feedback information on the first HARQ codebook, so as to distinguish between NACK feedback caused by the failure to decode the first data and NACK feedback caused by the failure to receive the first data.

Specifically, the terminal device and the network device can agree in advance on the number of bits occupied by the first HARQ feedback information on the first HARQ codebook, depending on whether the first resource includes the second resource.

The first resource can include resources where the probability of uplink/downlink transmission conflict for the terminal device is greater than zero. This can be understood as the first resource being a range of resources that may only include resources where the probability of uplink/downlink transmission conflict for the terminal device is greater than zero; or, the range may include both resources where the probability of uplink/downlink transmission conflict for the terminal device is greater than zero and resources where the probability of uplink/downlink transmission conflict for the terminal device is equal to zero. A resource where the probability of uplink/downlink transmission conflict for the terminal device is greater than zero can be understood as the terminal device having a greater than zero probability of uplink/downlink transmission conflict on that resource, or the terminal device potentially having uplink/downlink transmission conflict on that resource, or the terminal device having a greater than zero possibility of uplink/downlink transmission conflict on that resource.

The first resource can be pre-configured, standard-defined, or agreed upon in advance by the terminal device and the network device. For example, the terminal device can report information, and the network device can determine the resources where the terminal device actually has uplink and downlink transmission conflicts based on this information. If the information reported by the terminal has a certain degree of error, the network device can also determine the resources where the terminal device may have uplink and downlink transmission conflicts based on this information. This application does not limit this. For example, the network device and the terminal device determine that time slots x to x+3 are time slots where the probability of uplink and downlink transmission conflicts of the terminal device is greater than zero.

The second resource can be a resource used by the terminal device to receive the first data. In other words, the terminal device can receive the first data on the second resource.

It is understood that the resources in this application example can be time-domain resources, frequency-domain resources, or spatial-domain resources. Time-domain resources can be frames, subframes, time slots, sub-time slots, time slot symbols, or other time-domain resources. Frequency-domain resources can be subcarrier spaces (SCS), resource blocks (RBs), resource block groups (RBGs), BWPs, or other frequency-domain resources. Spatial-domain resources can be codewords, layers, antenna ports, or other spatial-domain resources. This application embodiment does not limit these aspects. For ease of explanation, this application embodiment uses time-domain resources as an example.

In scenario A, the first resource includes the second resource.

If the first resource includes the second resource, the network device can determine that the terminal device may have uplink/downlink transmission conflicts on the second resource, meaning the terminal device may not have received the first data on the second resource. In other words, the network device can determine that the probability of the terminal device having uplink/downlink transmission conflicts on the second resource is greater than zero, meaning the probability of the terminal device not receiving the first data on the second resource is greater than zero.

As can be seen, if the first HARQ feedback information corresponding to the first data is NACK, the network device cannot determine whether the specific reason for the NACK is unsuccessful decoding of the first data or failure to receive the first data. Therefore, in order for the network device to determine whether the specific reason for the NACK is unsuccessful decoding of the first data or failure to receive the first data, the terminal device can determine the two bits on the first HARQ codebook corresponding to the first HARQ feedback information, thereby distinguishing between NACK feedback caused by unsuccessful decoding of the first data and NACK feedback caused by failure to receive the first data.

Furthermore, if the terminal device experiences uplink/downlink transmission conflicts on the second resource and fails to receive the first data on the second resource, the terminal device can determine that the two bits of the first HARQ feedback information in the first HARQ codebook are set to a first value. That is, the first value indicates that the first HARQ feedback information is NACK, and the specific reason for the NACK feedback is that the first data was not received.

If there are no uplink or downlink transmission conflicts on the second resource, and the terminal device receives the first data on the second resource but fails to decode it, the terminal device can determine that the two bits of the first HARQ feedback information in the first HARQ codebook are a second value. That is, the second value is used to indicate that the first HARQ feedback information is NACK, and the specific reason for the NACK feedback is that the first data was not successfully decoded.

If there are no uplink or downlink transmission conflicts on the second resource, and the terminal device receives the first data on the second resource and successfully decodes the first data, the terminal device can determine that the value of two bits in the first HARQ codebook for the first HARQ feedback information is a third value. That is, the third value is used to indicate that the first HARQ feedback information is ACK.

The first, second, and third values can be pre-configured, standard-defined, or agreed upon in advance between the terminal device and the network device. This application does not limit these values.

For example, the first, second, and third values are 00, 01, and 10, respectively. That is, if the first HARQ feedback information has two bits in the first HARQ codebook that are 00, it indicates that the terminal device experienced uplink/downlink transmission conflicts on the second resource, resulting in the failure to receive the first data; therefore, the terminal device sends a NACK. If the first HARQ feedback information has two bits in the first HARQ codebook that are 01, it indicates that the terminal device received the first data on the second resource but failed to successfully decode it; therefore, the terminal device sends a NACK. If the first HARQ feedback information has two bits in the first HARQ codebook that are 10, it indicates that the terminal device received the first data on the second resource and successfully decoded it; therefore, the terminal device sends an ACK.

In scenario B, the first resource does not include the second resource.

If the first resource does not include the second resource, the network device can determine that the terminal device cannot have uplink or downlink transmission conflicts on the second resource, meaning the terminal device cannot fail to receive the first data on the second resource. In other words, the network device can determine that the probability of the terminal device having uplink or downlink transmission conflicts on the second resource is zero, meaning the probability of the terminal device failing to receive the first data on the second resource is zero.

As can be seen, if the first HARQ feedback information corresponding to the first data is NACK, the network device can determine whether the specific reason for the NACK is that the first data was not successfully decoded or was not received. Therefore, in order to reduce signaling overhead, the terminal device can determine that the first HARQ feedback information corresponds to a bit in the first HARQ codebook.

In one possible implementation, the first HARQ codebook can be a semi-static HARQ codebook or a dynamic HARQ codebook. This application does not limit this specific implementation.

If the first HARQ codebook is a semi-static HARQ codebook, then the first HARQ codebook can include both the HARQ feedback information (feedback of its true ACK or NACK) corresponding to the data when there is a PDSCH transmission opportunity and data is actually transmitted on that PDSCH transmission opportunity, and the HARQ feedback information (feedback of NACK) of that PDSCH transmission opportunity when there is a PDSCH transmission opportunity but data is not actually transmitted on that PDSCH transmission opportunity.

If the first HARQ codebook is a dynamic HARQ codebook, then the first HARQ codebook may only include the HARQ feedback information (feedback of its true ACK or NACK) corresponding to the data when there is a PDSCH transmission opportunity and the data is actually transmitted on that PDSCH transmission opportunity.

The PDSCH transmission timing, also known as the PDSCH reception timing, can be understood as the PDSCH used for data transmission. For example, the first PDSCH transmission timing is the first PDSCH used for data transmission, and the second PDSCH transmission timing is the second PDSCH used for data transmission.

In other words, if the first HARQ codebook is a semi-static HARQ codebook, it can include both first and second HARQ feedback information. If the first HARQ codebook is a dynamic HARQ codebook, it can only include the first HARQ feedback information.

Specifically, the first HARQ feedback information is the HARQ feedback information corresponding to the first data transmitted during the first PDSCH transmission opportunity when there is a first PDSCH transmission opportunity and the network device actually transmits the first data during the first PDSCH transmission opportunity. Furthermore, the first HARQ feedback information will provide its actual ACK or NACK.

The second HARQ feedback information is the HARQ feedback information corresponding to the second PDSCH transmission opportunity when there is an opportunity for second PDSCH transmission but the network device does not actually transmit data during the second PDSCH transmission opportunity. It can be understood that the second HARQ feedback information can correspond to a third resource, which can be a resource used by the terminal device to receive third data. The third data does not necessarily have to be data sent by the network device to the terminal device. Furthermore, the second HARQ feedback information will only return a NACK.

It is evident that regardless of whether the first resource includes the third resource or not, the second HARQ feedback information corresponding to the third resource is NACK. Network devices can also determine that the specific reason for the NACK in the second HARQ feedback information is that the network device did not send data to the terminal device. Therefore, to reduce signaling overhead, the terminal device can determine that the second HARQ feedback information corresponds to a bit in the first HARQ codebook.

For example, the first HARQ codebook can be a semi-static HARQ codebook. Figure 8 is a schematic diagram of a first HARQ codebook provided in an embodiment of this application. As shown in Figure 8, it includes four downlink time slots (i.e., time slot x to time slot x+3) and one uplink time slot (i.e., time slot x+4). One PDSCH (i.e., PDSCH1 to PDSCH4) is included in one downlink time slot, and one PUCCH (i.e., PUCCH1) is included in one uplink time slot. The network device can send data #1 through PDSCH1 in time slot x and send data #2 through PDSCH3 in time slot x+2. The terminal device can send the semi-static HARQ codebook #1 to the network device through PUCCH1 in time slot x+4.

If time slots x and x+1 are time slots where the probability of uplink/downlink transmission collisions at the terminal device is greater than zero, as determined by the network device and the terminal device, and the terminal device experiences uplink/downlink collisions in time slot x, resulting in the terminal device not receiving data #1 in time slot x, then the HARQ semi-static codebook #1 fed back by the terminal device to the network device consists of 5 bits, including 4 HARQ feedback messages.

Specifically, HARQ feedback information #11 located at bits 0 and 1 indicates a NACK corresponding to data #1 transmitted on PDSCH1. This means the terminal device did not receive data #1.

HARQ feedback information #21 located at bit 3 indicates a NACK corresponding to PDSCH2, which did not transmit data. This means the network device did not send data to the terminal device.

HARQ feedback information #31 located at bit 4 indicates the ACK or NACK corresponding to data #2 transmitted on PDSCH3. That is, whether the network device successfully decoded data #2 or failed to decode data #2.

HARQ feedback information #41 located at bit 5 indicates a NACK corresponding to PDSCH4, which did not transmit data. This means the network device did not send data to the terminal device.

For example, the first HARQ codebook can be a dynamic HARQ codebook. Figure 9 is a schematic diagram of another first HARQ codebook provided in an embodiment of this application. As shown in Figure 9, it includes four downlink time slots (i.e., time slot x to time slot x+3) and one uplink time slot (i.e., time slot x+4). One PDSCH (i.e., PDSCH1 to PDSCH4) is included in one downlink time slot, and one PUCCH (i.e., PUCCH1) is included in one uplink time slot. The network device can send data #1 through PDSCH1 in time slot x and send data #2 through PDSCH3 in time slot x+2. The terminal device can send the HARQ dynamic codebook #2 to the network device through PUCCH1 in time slot x+4.

If time slots x and x+1 are time slots where the probability of uplink/downlink transmission collisions at the terminal device is greater than zero, as determined by the network device and the terminal device, and the terminal device experiences uplink/downlink collisions in time slot x, resulting in the terminal device not receiving data #1 in time slot x, then the HARQ state codebook #2 fed back by the terminal device to the network device consists of 3 bits, including 2 HARQ feedback messages.

HARQ feedback information #12 located at bits 0 and 1 indicates a NACK for data #1 transmitted on PDSCH1. This means the terminal device did not receive data #1.

HARQ feedback information #22, located at bit 2, indicates whether the data #2 transmitted on PDSCH3 received an ACK or NACK. That is, whether the network device successfully decoded data #2 or failed to decode it.

S703, when the first resource includes the second resource and the first HARQ feedback information is NACK, the network device sends the second data to the terminal device, and the terminal device receives the second data from the network device accordingly.

In this embodiment of the application, after the network device receives the first HARQ codebook from the terminal device, the network device can determine whether the first resource includes the second resource.

If the first resource includes the second resource, the network device can determine that the terminal device may have uplink/downlink transmission conflicts on the second resource, meaning the terminal device may not have received the first data on the second resource. In other words, the network device can determine that the probability of the terminal device having uplink/downlink transmission conflicts on the second resource is greater than zero, meaning the probability of the terminal device not receiving the first data on the second resource is greater than zero.

If the first resource does not include the second resource, the network device can determine that the terminal device cannot have uplink or downlink transmission conflicts on the second resource, meaning the terminal device cannot fail to receive the first data on the second resource. In other words, the network device can determine that the probability of the terminal device having uplink or downlink transmission conflicts on the second resource is zero, meaning the probability of the terminal device failing to receive the first data on the second resource is zero.

It is understandable that if the first resource includes the second resource, and the first HARQ feedback information corresponding to the first data in the first HARQ codebook is NACK, the network device can determine that the specific reason for the first HARQ feedback information being NACK may be that the terminal device did not receive the first data. If the first resource includes the second resource, and the first HARQ feedback information corresponding to the first data in the first HARQ codebook is NACK, the network device can determine that the specific reason for the first HARQ feedback information being NACK may be that the terminal device received the first data but failed to successfully decode it.

Therefore, to improve data transmission efficiency, if the first resource includes the second resource and the first HARQ feedback information corresponding to the first data is NACK, the network device can send the second data to the terminal device. The second data can be data that can be independently decoded by the terminal device after retransmission of the first data; for example, the redundant version of the second data can be RV0 or RV3. In other words, even if the specific reason for the first HARQ feedback information being NACK might be that the terminal device did not receive the first data, the network device can send data to the terminal device that can be independently decoded by the terminal device without relying on the first data, thus improving retransmission efficiency.

If the first resource does not include the second resource and the first HARQ feedback information corresponding to the first data is NACK, the network device can send the second data or the fourth data to the terminal device. The fourth data can be data that cannot be independently decoded by the terminal device after retransmission of the first data; for example, the redundant version of the fourth data can be RV2 or RV1. In other words, if the specific reason for the first HARQ feedback information being NACK is that the terminal device received the first data but failed to decode it, the network device can send data that can be independently decoded by the terminal device without relying on the first data, or it can send data that requires the first data to be independently decoded by the terminal device.

In one possible implementation, the network device and the terminal device may agree in advance on the number of bits occupied by the first HARQ feedback information in the first HARQ codebook.

[Corrected according to Rule 91, 2025]
Specifically, the terminal device and the network device can agree in advance on the number of bits occupied by the first HARQ feedback information on the first HARQ codebook, depending on whether the first resource includes the second resource.

If the first resource includes the second resource, the first HARQ feedback information can correspond to two bits on the first HARQ codebook.

Specifically, if the two bits of the first HARQ feedback information in the first HARQ codebook are of the first value, the network device can determine that the first HARQ feedback information is NACK, and that the terminal device has uplink and downlink transmission conflicts on the second resource.

If the two bits of the first HARQ feedback information in the first HARQ codebook are of the second value, the network device can determine that the first HARQ feedback information is NACK, and that there is no uplink or downlink transmission conflict on the second resource for the terminal device.

If two bits in the first HARQ feedback information are of the third value, the network device can determine that the first HARQ feedback information is an ACK.

Furthermore, if the network device determines that the first resource includes the second resource, the first HARQ feedback information is NACK, and the terminal device has uplink and downlink transmission conflicts on the second resource, the network device will then send the second data to the terminal device.

If the first resource does not include the second resource, the first HARQ feedback information can correspond to two bits on the first HARQ codebook.

In one possible implementation, the network device can send multiple reference signals (RS) to the terminal device. The terminal device can send multiple channel state information (CSI) messages to the network device.

The reference signal is also known as a demodulation reference signal (DMRS), channel state information reference signal (CSI-RS), phase tracking reference signal (PTRS), and sounding reference signal (SRS), etc., and this application does not limit the specific type of reference signal. One of the multiple reference signals corresponds to one of the multiple CSIs.

To conserve resources, terminal devices can send HARQ feedback information and CSI to network devices using the same PUCCH. In other words, in addition to HARQ feedback information being transmitted on the PUCCH, CSI is also transmitted on the PUCCH, and both HARQ feedback information and CSI can reuse the same PUCCH. Since the information carried by a single PUCCH is limited, terminal devices can select the highest priority CSI from multiple CSIs and reuse it with the HARQ feedback information on the same PUCCH.

It is understandable that the terminal device may receive the reference signal corresponding to the high-priority CSI, or the terminal device may not receive the reference signal corresponding to the high-priority CSI from the network device due to uplink and downlink transmission conflicts.

When the terminal device does not receive the reference signal corresponding to the higher-priority CSI, the higher-priority CSI is considered invalid. Therefore, to avoid the terminal device from feeding back invalid CSIs, thereby increasing the amount of effective information fed back by CSIs and reducing resource waste, the embodiments of this application may further perform the following steps A1-A3.

In step A1, the network device sends a first reference signal and a second reference signal to the terminal device. Correspondingly, the terminal device receives the first reference signal from the network device.

The first reference signal has a lower priority than the second reference signal.

In step A2, if there is an uplink/downlink transmission conflict on the fourth resource, the terminal device sends a first CSI to the network device, and the network device receives the first CSI from the terminal device.

The fourth resource can be a resource used by the terminal device to receive the second reference signal, meaning the terminal device can receive the second reference signal on the fourth resource. The first CSI and the first HARQ codebook can be carried in the same PUCCH (i.e., the first PUCCH), and the first CSI can correspond to the first reference signal.

Step A3: The network device determines that the terminal device has uplink and downlink transmission conflicts on the fourth resource.

In other words, the priority of the first reference signal is lower than that of the second reference signal; that is, the priority of the first CSI corresponding to the first reference signal is lower than that of the second CSI corresponding to the second reference signal. The terminal device should send the first HARQ codebook and the second CSI to the network device via the first PUCCH. However, due to uplink/downlink transmission conflicts on the fourth resource, the terminal device did not receive the second reference signal on the fourth resource, meaning the second CSI is invalid. Therefore, the terminal device sends the first HARQ codebook and the first CSI to the network device via the first PUCCH to increase the amount of effective information in the CSI feedback and reduce resource waste. Upon receiving the first HARQ codebook and the first CSI carried on the same PUCCH, the network device can determine that the terminal device chose to discard the higher-priority second CSI and feed back the lower-priority first CSI because of uplink/downlink transmission conflicts on the fourth resource.

It is understood that the above embodiments of this application can be implemented individually or in combination with each other, and the embodiments of this application are not limited.

The methods provided by the embodiments of this application have been described above with reference to the accompanying drawings. The apparatus provided by the embodiments of this application will be described below with reference to the accompanying drawings.

Based on the same technical concept, embodiments of this application provide a communication device, which includes a module/unit/means for executing the method performed by the device in the above-described method embodiments. This module/unit/means can be implemented in software, or in hardware, or implemented by hardware executing corresponding software.

For example, referring to FIG10, a schematic diagram of a communication device 1000 is provided, which includes a transceiver module 1001 and a processing module 1002.

When the device 1000 is a network device, the functions of each module of the device 1000 are as follows:

Transceiver module 1001 is used to send first data to terminal device;

The transceiver module 1001 is further configured to receive a first HARQ codebook from the terminal device, wherein the first HARQ codebook includes first HARQ feedback information, and the first HARQ feedback information corresponds to the first data;

The transceiver module 1001 is further configured to send second data to the terminal device when the first resource includes the second resource and the first HARQ feedback information is NACK, wherein the first resource includes resources in which the probability of uplink and downlink transmission conflicts of the terminal device is greater than zero, the second resource is a resource for the terminal device to receive the first data, and the second data is data that can be independently decoded by the terminal device after the network device performs retransmission processing on the first data.

Alternatively, when the device 1000 is a terminal device, the functions of each module of the device 1000 are as follows:

The transceiver module 1001 is used to send a first HARQ codebook to the network device, wherein the first HARQ codebook includes first HARQ feedback information, and the first HARQ feedback information corresponds to the first data sent by the network device to the terminal device.

The transceiver module 1001 is further configured to receive second data from the network device when the first resource includes the second resource and the first HARQ feedback information is NACK, wherein the first resource includes resources where the probability of uplink and downlink transmission conflicts of the terminal device is greater than zero, the second resource is a resource used by the terminal device to receive the first data, and the second data is data that can be independently decoded by the terminal device after the network device performs retransmission processing on the first data.

In practical implementation, the above-mentioned device 1000 can have various product forms. Several possible product forms are introduced below.

Referring to Figure 11, which is a schematic diagram of another communication device, the communication device 1100 includes a processor 1101 and an interface circuit 1102. The interface circuit 1102 is used to receive signals from other communication devices outside the communication device and transmit them to the processor 1101, or to send signals from the processor 1101 to other communication devices outside the communication device. The processor 1101 is used to implement the methods executed by the network device or terminal device in the above method embodiments through logic circuits or execution instructions.

The processor 1101 and the interface circuit 1102 are coupled to each other. It is understood that the interface circuit 1102 can be a transceiver or an input/output interface. Optionally, the communication device 1100 may also include a memory 1103 for storing instructions executed by the processor 1101, or storing input data required by the processor 1101 to execute instructions, or storing data generated after the processor 1101 executes instructions.

When the aforementioned communication device is a module applied to a network device or a terminal device, the module implements the functions of the network device or the terminal device in the above method embodiments. The module receives information from other modules (such as a radio frequency module or antenna) in the network device or the terminal device, where the information is sent from the terminal device to the network device or from the network device to the terminal device; or, the module sends information to other modules (such as a radio frequency module or antenna) in the network device or the terminal device, where the information is sent from the network device to the terminal device or from the terminal device to the network device.

It should be understood that the processor mentioned in the embodiments of this application can be implemented in hardware or software. When implemented in hardware, the processor can be a logic circuit, integrated circuit, etc. When implemented in software, the processor can be a general-purpose processor, implemented by reading software code stored in memory.

For example, the processor can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general-purpose processor can be a microprocessor or any conventional processor.

It should be understood that the memory mentioned in the embodiments of this application can be volatile memory or non-volatile memory, or may include both volatile and non-volatile memory. Non-volatile memory can be read-only memory (ROM), programmable read-only memory (PROM), erasable programmable read-only memory (EPROM), electrically erasable programmable read-only memory (EEPROM), or flash memory. Volatile memory can be random access memory (RAM), which is used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as static random access memory (SRAM), dynamic random access memory (DRAM), synchronous dynamic random access memory (SDRAM), double data rate synchronous dynamic random access memory (DDR SDRAM), enhanced synchronous dynamic random access memory (ESDRAM), synchronous linked dynamic random access memory (SLDRAM), and direct rambus RAM (DR RAM).

It should be noted that when the processor is a general-purpose processor, DSP, ASIC, FPGA, or other programmable logic device, discrete gate or transistor logic device, or discrete hardware component, the memory (storage module) can be integrated into the processor.

It should be noted that the memories described herein are intended to include, but are not limited to, these and any other suitable types of memories.

Based on the same technical concept, embodiments of this application also provide a computer-readable storage medium storing a computer program or instructions, which, when executed by a processor, causes the method executed by the network device or terminal device in the above method embodiments to be implemented.

Based on the same technical concept, this application also provides a computer program product, which includes a computer program or instructions. When the computer program or instructions are executed by a processor, the method executed by the network device or terminal device in the above method embodiments is implemented.

Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

This application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to this application. It should be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in one or more blocks of the flowchart illustrations and/or one or more blocks of the block diagrams.

These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means that implement the functions specified in one or more flowcharts and/or one or more block diagrams.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer-implemented process, such that the instructions, which execute on the computer or other programmable apparatus, provide steps for implementing the functions specified in one or more flowcharts and/or one or more block diagrams.

Claims (16)

A communication method, characterized in that it includes: The network device sends the first data to the terminal device; The network device receives a first Hybrid Automatic Repeat Request (HARQ) codebook from the terminal device, wherein the first HARQ codebook includes first HARQ feedback information, and the first HARQ feedback information corresponds to the first data. When the first resource includes the second resource and the first HARQ feedback information is a negative acknowledgment (NACK), the network device sends second data to the terminal device. The first resource includes resources where the probability of uplink/downlink transmission conflict is greater than zero. The second resource is a resource used by the terminal device to receive the first data. The second data is data that can be independently decoded by the terminal device after the network device performs retransmission processing on the first data. The method according to claim 1, characterized in that, When the first resource includes the second resource, the first HARQ feedback information corresponds to two bits on the first HARQ codebook. The method according to claim 2, characterized in that the method further comprises: If the two bits are set to the first value, the network device determines that the first HARQ feedback information is NACK, and that the terminal device has uplink and downlink transmission conflicts on the second resource. According to the method of claim 3, wherein when the first resource includes the second resource and the first HARQ feedback information is a negative acknowledgment (NACK), the network device sends second data to the terminal device, including: When the first resource includes the second resource, the first HARQ feedback information is NACK, and the terminal device has uplink and downlink transmission conflicts on the second resource, the network device sends the second data to the terminal device. The method according to any one of claims 1-4 is characterized in that the first HARQ codebook is a semi-static codebook, the first HARQ codebook further includes second HARQ feedback information, the second HARQ feedback information corresponds to a third resource, the third resource is a resource for the terminal device to receive third data, the third data is not data sent by the network device to the terminal device, and the second HARQ feedback information corresponds to a bit on the first HARQ codebook. The method according to any one of claims 1-5, characterized in that the method comprises: The network device sends a first reference signal and a second reference signal to the terminal device, wherein the first reference signal has a lower priority than the second reference signal. The network device receives first channel state information (CSI) from the terminal device. The first CSI and the first HARQ codebook are carried in the same physical uplink control channel (PUCCH). The first CSI corresponds to the first reference signal. The network device determines that the terminal device has an uplink and downlink transmission conflict on a fourth resource, which is a resource used by the terminal device to receive the second reference signal. A communication method, characterized in that it includes: The terminal device sends a first Hybrid Automatic Repeat Request (HARQ) codebook to the network device, wherein the first HARQ codebook includes first HARQ feedback information, and the first HARQ feedback information corresponds to the first data sent by the network device to the terminal device. When the first resource includes the second resource and the first HARQ feedback information is a negative acknowledgment (NACK), the terminal device receives second data from the network device. The first resource includes resources where the probability of uplink/downlink transmission conflict is greater than zero. The second resource is a resource used by the terminal device to receive the first data. The second data is data that can be independently decoded by the terminal device after the network device performs retransmission processing on the first data. The method according to claim 7, characterized in that, When the first resource includes the second resource, the first HARQ feedback information corresponds to two bits on the first HARQ codebook. The method according to claim 8, characterized in that the method further comprises: In the event of uplink and downlink transmission conflicts on the second resource, the terminal device determines that the two bits are of a first value, which is used to indicate that the first HARQ feedback information is NACK. According to the method of claim 9, wherein when the first resource includes the second resource and the first HARQ feedback information is NACK, the terminal device receives second data from the network device, including: When the first resource includes the second resource, the first HARQ feedback information is NACK, and the terminal device has uplink and downlink transmission conflicts on the second resource, the terminal device receives the second data from the network device. The method according to any one of claims 7-10 is characterized in that the first HARQ codebook is a semi-static codebook, the first HARQ codebook further includes second HARQ feedback information, the second HARQ feedback information corresponds to a third resource, the third resource is a resource for the terminal device to receive third data, the third data is not data sent by the network device to the terminal device, and the second HARQ feedback information corresponds to a bit on the first HARQ codebook. The method according to any one of claims 7-11, characterized in that the method comprises: The terminal device receives a first reference signal from the network device; In the event of uplink/downlink transmission conflict on the fourth resource, the terminal device sends a first CSI to the network device. The first CSI and the first HARQ codebook are carried in the same PUCCH. The first CSI corresponds to the first reference signal. The fourth resource is a resource used by the terminal device to receive a second reference signal. The priority of the first reference signal is lower than that of the second reference signal. A communication device, characterized in that the communication device includes a module for performing the method as described in any one of claims 1-6, or a module for performing the method as described in any one of claims 7-12. A communication device, characterized in that the communication device includes a processor, the processor being configured to perform the method as described in any one of claims 1-6, or to perform the method as described in any one of claims 7-12. A computer-readable storage medium, characterized in that the computer-readable storage medium is used to store a computer program that, when the computer program is run on a computer, causes the method as described in any one of claims 1-6 to be performed, or causes the method as described in any one of claims 7-12 to be performed. A computer program product, characterized in that the computer program product includes a computer program that, when the computer program is run on a computer, causes the method as described in any one of claims 1-6 to be executed, or causes the method as described in any one of claims 7-12 to be executed.