Method for wireless communication

Abstract

To provide a method for a hybrid automatic repeat request (HARQ).SOLUTION: There is provided a method for wireless communication, and a network device is configured to: transmit a scheduling message to a terminal device; transmit data to the terminal device according to the scheduling message; detect HARQ feedback from the terminal device; determine a resource ID of a resource where the feedback is detected; and control subsequent transmission or re-transmission based upon the received HARQ feedback and resource ID. Information associated with the HARQ feedback represents one of a process ID for HARQ feedback, and the terminal device or a cumulative count of scheduling messages transmitted for the process ID.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] TECHNICAL FIELD Non-limiting and exemplary embodiments of the present disclosure relate generally to the technical field of wireless communications, and more particularly, to methods and devices for Hybrid Automatic Repeat Request (HARQ). [Background technology]

[0002] This section introduces aspects that may make the disclosure more understandable, and therefore, statements in this section are to be read in this light, and are not to be understood as admissions that any aspect of the invention is or is not disclosed in the prior art.

[0003] To improve the reliability of transmission, HARQ mechanisms are widely used in communication systems developed by the Third Generation Partnership Project (3GPP), such as the fourth generation (4G) wireless communication system called LTE (Long Term Evolution) and the fifth generation (5G) wireless communication system called NR (New Radio).

[0004] In HARQ, the receiver feeds back an acknowledgement (ACK) to the transmitter if the data from the transmitter is correctly detected, and a negative acknowledgement (NACK) if the data is not correctly detected. Then, the transmitter performs a new transmission or a retransmission depending on whether an ACK or a NACK is received from the receiver. Therefore, the ACK / NACK feedback (also called HARQ feedback) is important for scheduling data transmission. Summary of the Invention [Problem to be solved by the invention]

[0005] Various embodiments of the present disclosure are primarily directed to providing an enhanced HARQ feedback mechanism for wireless communications.

[0006] A first aspect of the present disclosure provides a method for wireless communication, comprising: transmitting a scheduling message including information related to HARQ feedback to a terminal device, transmitting data to the terminal device according to the scheduling message, receiving HARQ feedback from the terminal device, and controlling subsequent transmission or retransmission based on the received HARQ feedback, where the information related to HARQ feedback indicates at least one of a process ID for HARQ feedback and a cumulative number of scheduling messages transmitted for the terminal device or the process ID.

[0007] A second aspect of the present disclosure provides another method, comprising: transmitting a scheduling message to a terminal device, transmitting data to the terminal device according to the scheduling message, detecting HARQ feedback from the terminal device, determining a resource ID of a resource for which HARQ feedback is detected, and controlling a subsequent transmission or retransmission based on the received HARQ feedback and the resource ID, where the resource ID includes an identifier of a resource set group associated with the resource, the resource set group including one or more resource sets, and a resource set including one or more resources.

[0008] In a third aspect of the present disclosure, there is provided another method, comprising: transmitting a coding configuration to a terminal device indicating an encoding type of a static HARQ codebook for HARQ feedback, transmitting data to the terminal device, detecting HARQ feedback for the data from the terminal device based on the indicated encoding type, and controlling subsequent transmission or retransmission based on the detected HARQ feedback.

[0009] A fourth aspect of the present disclosure provides a method implemented by a terminal device, comprising: receiving a scheduling message from a network device, the scheduling message including information related to HARQ feedback; detecting data from the network device according to the scheduling message; and sending HARQ feedback to the network device based on information related to the HARQ feedback, the information related to the HARQ feedback indicating at least one of a process ID for HARQ feedback and a cumulative number of scheduling messages sent for the terminal device or the process ID.

[0010] A fifth aspect of the present disclosure provides another method implemented by a terminal device, comprising: receiving data from a network device; and in response to determining to retransmit feedback for the data an i-th time, selecting a resource from the i-th resource set group; and retransmitting the feedback for the data on the selected resource, where i is a positive integer, the resource set group includes one or more resource sets, and the resource set includes one or more feedback resources.

[0011] A sixth aspect of the present disclosure provides another method implemented by a terminal device, comprising: receiving a coding configuration indicating a type of encoding of a static HARQ codebook for HARQ feedback from a network device, receiving data from the network device, generating HARQ feedback for the data based on the coding configuration, and transmitting the HARQ feedback to the network device.

[0012] In a seventh aspect of the present disclosure, there is provided an apparatus for wireless communication, the apparatus including a processor and a memory, the memory having instructions executable by the processor and which, when executed by the processor, cause the apparatus to operate to perform a method according to any of the first, second or third aspects of the present disclosure.

[0013] In an eighth aspect of the present disclosure, there is provided another apparatus for wireless communication, the apparatus including a processor and a memory, the memory having instructions executable by the processor and which, when executed by the processor, cause the apparatus to operate to perform a method according to any of the fourth, fifth or sixth aspects of the present disclosure.

[0014] In a ninth aspect of the present disclosure, there is provided a computer readable medium having stored thereon a computer program which, when executed by an apparatus, causes the apparatus to perform a method according to any of the first, second or third aspects of the present disclosure.

[0015] In a tenth aspect of the present disclosure, there is provided a computer readable medium having stored thereon a computer program which, when executed by an apparatus, causes the apparatus to perform a method according to any of the fourth, fifth or sixth aspects of the present disclosure.

[0016] Embodiments of the present disclosure can improve HARQ performance and improve resource efficiency. [Brief description of the drawings]

[0017] The above and other aspects, features, and advantages of various embodiments of the present disclosure will become more fully apparent from the following detailed description taken in conjunction with the accompanying drawings, in which like reference numerals represent like or equivalent elements, and in which the drawings are presented to facilitate a better understanding of the embodiments of the present disclosure and are not necessarily drawn to scale.

[0018] [Figure 1] FIG. 1 illustrates an exemplary wireless communication network in which embodiments of the present disclosure may be implemented.

[0019] [Diagram 2] FIG. 2 illustrates an example of determining the payload size of HARQ feedback based on the proposed indication in DCI according to an embodiment of the present disclosure.

[0020] [Diagram 3] FIG. 3 illustrates an example of determining ACK / NACK bits to be retransmitted based on the proposed HARQ-PUCCH process ID according to an embodiment of the present disclosure.

[0021] [Figure 4] FIG. 4 illustrates an example of a three-dimensional (3D) indication of a resource according to an embodiment of the present disclosure.

[0022] [Diagram 5] FIG. 5 illustrates an example of determining resources for ACK / NACK feedback based on the concept of resource set groups according to an embodiment of the present disclosure.

[0023] [Figure 6] FIG. 6 illustrates a schematic diagram of an example of Type A and Type B encoding for HARQ feedback according to an embodiment of the present disclosure.

[0024] [Figure 7] FIG. 7 illustrates a flowchart of a method that may be implemented by a network device according to an embodiment of the present disclosure. [Figure 8] FIG. 8 illustrates a flowchart of a method that may be implemented by a network device according to an embodiment of the present disclosure. [Figure 9] FIG. 9 illustrates a flowchart of a method that may be implemented by a network device according to an embodiment of the present disclosure.

[0025] [Figure 10] FIG. 10 shows a flowchart of a method that may be implemented by a terminal device according to an embodiment of the present disclosure. [Figure 11] FIG. 11 shows a flowchart of a method that may be implemented by a terminal device according to an embodiment of the present disclosure. [Figure 12] FIG. 12 shows a flowchart of a method that may be implemented by a terminal device according to an embodiment of the present disclosure.

[0026] [Figure 13] FIG. 13 illustrates a simplified block diagram of an apparatus embodied as or provided in a terminal device or a network device according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0027] Hereinafter, the principles and principles of the present disclosure will be described with reference to exemplary embodiments. It should be understood that all of these embodiments are merely provided to enable those skilled in the art to better understand and further implement the present disclosure, and are not intended to limit the scope of the present disclosure. For example, features illustrated or described as part of one embodiment can be used with another embodiment to produce yet another embodiment. For clarity, not all features of an actual implementation are described herein.

[0028] References herein to "one embodiment," "an embodiment," "an exemplary embodiment," or the like indicate that the described embodiment may include a particular feature, structure, or characteristic, but not necessarily all embodiments include the particular feature, structure, or characteristic. Moreover, such phrases do not necessarily refer to the same embodiment. Furthermore, when a particular feature, structure, or characteristic is described with respect to an embodiment, whether or not explicitly stated, it is intended that it is within the knowledge of one of ordinary skill in the art to apply such feature, structure, or characteristic with respect to other embodiments.

[0029] In this specification, terms such as "first" and "second" may be used to describe various elements, but it should be understood that these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, a first element can be referred to as a second element, and similarly, a second element can be referred to as a first element, without departing from the scope of the exemplary embodiments. As used herein, the term "and / or" includes any and all combinations of one or more of the listed terms.

[0030] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting to example embodiments. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise. It is further understood that as used herein, the terms "comprising," "having," and / or "including" specify the presence of stated features, elements, and / or components, etc., but do not exclude the presence or addition of one or more other features, elements, components, and / or combinations thereof.

[0031] In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0032] As used herein, the term "wireless communication network" refers to a network conforming to any suitable wireless communication standard, such as New Radio (NR), Long Term Evolution (LTE), LTE-Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), High-Speed ​​Packet Access (HSPA), etc. A "wireless communication network" may also be referred to as a "wireless communication system." Furthermore, communications between network devices in a wireless communication network, between network devices and terminal devices, or between terminal devices may be performed according to any suitable communication protocol, including, but not limited to, Global System for Mobile (GSM), Universal Mobile Telecommunications System (UMTS), LTE, NR, wireless local area network (WLAN) standards (such as the IEEE 802.11 standard), and / or other suitable wireless communication standards now known or developed in the future.

[0033] As used herein, the term "network device" refers to a network node in a wireless communication network that transmits and receives data and signals to and from terminal devices. A network device may refer to a base station (BS) or an access point (AP) depending on the terminology and technology applied. Examples of APs include Node B (NodeB or NB), Evolved Node B (eNodeB or eNB), NR NB (also called gNB), Remote Radio Unit (RRU), Radio Head (RH), Remote Radio Head (RRH), relays, and low power nodes such as femto and pico.

[0034] The term "terminal device" refers to any end device capable of wireless communication. As a non-limiting example, a terminal device may also be referred to as a communication device, user equipment (UE), subscriber station (SS), portable subscriber station (Portable Subscriber Station), mobile station (MS), or access terminal (AT). Terminal devices include, but are not limited to, mobile phones, cellular phones, smartphones, voice over IP (VoIP) phones, wireless local loop (WLL) phones, tablets, wearable terminal devices, personal digital assistants (PDAs), portable computers, desktop computers, image capture terminal devices such as digital cameras, gaming terminal devices, music storage and playback devices, in-vehicle wireless terminal devices, wireless endpoints, mobile stations, laptop-embedded equipment (LEE), laptop-mounted equipment (LME), USB dongles, smart devices, wireless customer-premises equipment (CPE), and the like. In the following description, the terms "terminal device", "communication device", "terminal", "user equipment", and "UE" may be used interchangeably.

[0035] As yet another example, in an Internet of Things (IOT) scenario, a terminal device may represent a machine or other device that performs monitoring and / or measurements and transmits results of such monitoring and / or measurements to another terminal device and / or network equipment. In this case, the terminal device may be a machine-to-machine (M2M) device, which in the 3GPP context is called a machine-type communication (MTC) device. As a particular example, the terminal device is a UE implementing the 3GPP narrow band internet of things (NB-IoT) standard. Examples of such machines or devices include sensors, metering devices such as power meters, industrial machines, or household or personal appliances (e.g., personal wearables such as refrigerators, televisions, clocks, etc.). In other scenarios, the terminal device may represent a vehicle or other equipment that can monitor and / or report operating conditions or other functions related to its operation.

[0036] As used in this specification, downlink (DL) transmission refers to a transmission from a network device to a UE, uplink (UL) transmission refers to a transmission from a UE to the network, and sidelink (SL) transmission refers to a transmission between UEs.

[0037] FIG. 1 illustrates an exemplary wireless communication network 100 in which embodiments of the present disclosure may be implemented. As illustrated, the communication network 100 may include one or more network devices, e.g., a network device 101 in the form of an eNB or a gNB. It should be understood that the network device 101 may be in the form of a Node B, a Base Transceiver Station (BTS) and / or a Base Station Subsystem (BSS), an Access Point (AP), etc. The network device 101 provides wireless connectivity to a set of terminal devices, e.g., terminal devices 102-1, 102-2, and 102-3, collectively referred to as "terminal devices 102." For convenience, only three terminal devices are shown in FIG. 1, but it should be understood that in practice there may be more or less terminal devices in the communication network.

[0038] Transmissions between the network device 101 and the terminal device 102 may be scheduled via scheduling messages, such as DL control information (DCI). Upon detecting a DCI for DL ​​scheduling, the terminal device 102 attempts to detect DL data transmissions (e.g., Physical Downlink Shared CHannel (PDSCH) transmissions) on resources indicated by the DCI.

[0039] It should be noted that the network device 101 may communicate with the terminal device 102 using one or more carriers in one or more frequency bands. The one or more frequency bands may include licensed and / or unlicensed bands.

[0040] One type of unlicensed spectrum operation, known as Licensed Assisted Access (LAA), has been studied and adopted by 3GPP. In an LAA system, control signaling, such as scheduling information in the DL and HARQ feedback in the UL, is transmitted in the licensed spectrum, while data transmission is performed in the unlicensed spectrum.

[0041] The other type of unlicensed spectrum operation being studied by 3GPP is called NR Unlicensed (NR-U), in which no support from licensed spectrum is available and both data and control transmissions are carried out in the unlicensed spectrum.

[0042] In unlicensed spectrum, before transmitting, a node must first have a Clear Channel Assessment (CCA), i.e., Listen before talk (LBT) must be performed before transmitting. If the LBT fails, the transmission will be blocked. The inventors of the present application have found that the failure of the LBT can cause problems for the HARQ mechanism.

[0043] According to the HARQ mechanism, the receiver (e.g., the terminal device 102) feeds back an ACK to the transmitter (e.g., the network device 101) if the data from the transmitter is correctly detected, and feeds back a NACK otherwise. Then, the transmitter performs a new transmission or a retransmission depending on whether an ACK or a NACK is fed back by the receiver. Therefore, the ACK / NACK feedback (also called HARQ feedback) is important for scheduling data transmission.

[0044] Errors in the HARQ mechanism can cause failure of ACK / NACK feedback or detection, so that the transmitter does not know whether the data was received correctly or not.

[0045] We have found that due to path loss, channel fading and / or interference, errors may occur during data transmission or HARQ feedback, which may lead to several problems for the HARQ mechanism, including DL missed detection, DL false alarm, UL missed detection and UL false alarm.

[0046] When DCI is transmitted by a transmitter but not detected by a receiver, DCI missed detection occurs. In such a case, the transmitter expects ACK / NACK feedback, but the ACK / NACK feedback is not provided by the receiver, resulting in an unclear problem on the transmitter side and the receiver side. Although DCI carried on a physical downlink control channel (PDCCH) has high decoding accuracy, the normal decoding error rate is about 1%, so DCI missed detection cannot be completely avoided.

[0047] To solve this problem, for one-time feedback (i.e., feedback related to a single PDSCH transmission), discontinuous transmission (DTX) detection may be employed at the transmitter (e.g., network device 101) side. For HARQ feedback with multiple multiplexing (i.e., feedback for multiple PDSCH transmissions), a Downlink Assignment Index (DAI) may be included in the DCI to solve the problem caused by DCI missed detection, except for DCI missed detection of the last one or more transmission opportunities. Based on the DAI field of the DCI, the UE will know the undetected PDCCH. This ensures that even if missed detection occurs, the UE has information about the length of the HARQ-ACK bits to be fed back as well as the gNB. For example, with a 2-bit DAI, the size of the feedback (i.e., the number of feedback bits) is ambiguous only if four consecutive DCIs are missed.

[0048] The problem caused by DCI missed detection of the last transmission opportunity can be solved by indicating different Physical Uplink Control CHannel (PUCCH) resources in each DCI and performing (multiple) blind detection of ACK / NACK in different PUCCH resources at the transmitter side.

[0049] Similarly, a DL false alarm occurs when DCI in the PDCCH is not transmitted but is detected by the UE, in which case the UE may feed back unscheduled resources and cause interference.

[0050] Another HARQ feedback error is called UL missed detection, where an ACK / NACK is transmitted by the receiver (e.g., UE) on the PUCCH but is not correctly detected by the transmitter (e.g., gNB). In particular, the NACK feedback from the UE may not be detected by the gNB, in which case the gNB performs a retransmission but only affects the current transmission opportunity. If the NACK is decoded by the gNB as an ACK, this may trigger higher layer ARQ, which reduces the transmission efficiency. If the ACK is detected as a NACK or DTX, unnecessary retransmissions are performed, which negatively affects the current transmission opportunity.

[0051] On the other hand, a UL false alarm occurs when an ACK / NACK is not sent but is received by the gNB. However, this is a rare case as it only occurs if a DL missed detection and a UL false alarm occur simultaneously.

[0052] In some scenarios, HARQ feedback for multiple data transmissions (e.g., PDSCH transmissions) may be provided over a single UL channel, e.g., a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH). In such cases, multiple ACK / NACK bits may be carried in the same PUCCH / PUSCH. In other words, one or more PDSCHs are associated with one PUCCH / PUSCH for HARQ feedback, and the PDSCHs associated with the same PUCCH / PUSCH may be referred to as a PDSCH set, or a transmission set. The association of PDSCHs (or DCIs scheduling PDSCHs) with PUCCHs / PUSCHs may be pre-determined or dynamically configured.

[0053] Furthermore, the timing and PUCCH resources for HARQ feedback may be indicated by the transmitter, e.g., gNB, via DCI. For example, there are 8 PUCCH resources per PUCCH resource set, and up to 4 PUCCH resource sets can be configured to the UE by Radio Resource Control (RRC) signaling. The PUCCH resource set used for ACK / NACK transmission may be selected based on the payload of the PUCCH bits, and the used PUCCH resources within the PUCCH resource set may be further indicated by DCI.

[0054] In 5G NR, HARQ feedback may use either of two modes of codebooks: static codebook or dynamic codebook. In static codebook, all possible timings and / or associations of DCI / PDSCH with PUCCH / PUSCH are considered when generating HARQ bits. This mode of codebook causes high payload on PUCCH / PUSCH, but can avoid DCI missed detection because the payload size (i.e., the number of HARQ-ACK bits to feed back) is predefined and static. HARQ feedback of DCI missed by the receiver is set to the default value NACK.

[0055] In the dynamic codebook for HARQ feedback, only the transmitted PDSCH is considered when generating HARQ bits to reduce the payload size. In such a case, the UE transmits HARQ feedback only if DCI is detected, and the feedback content, ACK or NACK, depends on whether the PDSCH scheduled by the detected DCI is correctly decoded. Therefore, if DCI is transmitted by the transmitter but not detected by the receiver (i.e., DCI detection failure occurs), no ACK / NACK is transmitted, which may cause unclear problems at the transmitter and receiver sides.

[0056] In addition to the above problems, operating in unlicensed bands in NR-U mode may bring more problems to the HARQ mechanism. For example, LBT failure may block the HARQ feedback transmission from the receiver side, and in such a case, how to make the transmitter aware of the DTX of the HARQ feedback is an open problem. Furthermore, how to provide the blocked HARQ feedback when resources are available should also be studied.

[0057] In some scenarios, when a gNB accesses a channel in an unlicensed spectrum, UL transmission from the UE side within the Channel Occupied Time (COT) of the gNB can be performed without another LBT if the gap between DL transmission from the gNB and UL transmission from the UE is not larger than a certain threshold, e.g., 16us. Therefore, to avoid HARQ feedback being blocked due to LBT failure, it is beneficial for the UE to feedback HARQ-ACK within the COT of the gNB. It should be noted that for HARQ feedback of the current PDSCH, either the COT associated with the current PDSCH or the COT associated with the next PDSCH may be used. However, considering the processing delay of the PDSCH at the UE side, it may be impossible to transmit HARQ feedback within 16us in some scenarios.

[0058] In the current NR system, the problem caused by the missed detection of one or more last transmission opportunities can be solved by indicating a different PUCCH resource in each transmitted DCI. However, this solution does not work well when the HARQ feedback bits of multiple PDSCH sets need to be transmitted simultaneously on a single PUCCH / PUSCH channel. For the purpose of illustration, assume that PDSCH set 1 and PDSCH set 2 are fed back on a single PUCCH / PUSCH resource, and each PDSCH set contains two PDSCHs. In this example, if the second PDSCH of PDSCH set 1 is not detected by mistake and the other PDSCHs are detected correctly, the UE will feedback three ACK bits. However, the gNB expects four ACK bits, and even if the gNB blindly detects on the multiple PUCCH resources indicated by the DCI of these PDSCHs, it cannot know that only three bits are transmitted by the UE.

[0059] Furthermore, if a PUCCH carrying ACK / NACK bits is blocked due to an LBT failure in an unlicensed band, the blocked PUCCH will be retransmitted automatically or based on a DCI trigger at the next PUCCH opportunity. However, if the length of the HARQ-ACK bits of the blocked PUCCH opportunity is unclear, a big problem will occur in decoding the next PUCCH.

[0060] The present disclosure provides methods, devices, and computer-readable media to address at least some of the above-mentioned problems and other problems. For example, some embodiments may address problems caused by missed detection of the last one or more DCI transmission opportunities. Alternatively, or in addition, some embodiments may avoid error propagation due to missed detection of unexpected DCI.

[0061] In some embodiments, to address the issue of ambiguity in the payload size of the ACK / NACK feedback and / or the location of one or more leaked PDSCHs and corresponding ACK / NACK bits due to DCI missed detection, one or more of a Cycled DAI, a HARQ PUCCH Processing ID, and a new feedback identifier are included in the scheduling message (e.g., DCI).

[0062] For illustration, along with the cyclic DAI, a counter DAI or a total DAI may be included in each DCI, where the counter DAI in the DCI indicates the total number of DCIs transmitted on the PDSCH set (i.e., one set of PDSCHs associated with the same PUCCH feedback occasion) up to the current time, and the total DAI in the DCI indicates the total number of DCIs transmitted on the PDSCH set when carrier aggregation is adopted. The total DAI in carrier aggregation contributes to solving the problem caused by the missed detection of one or more last transmission opportunities. However, in a single carrier deployment, there is no total DAI. The cyclic DAI indicates the cumulative number of DCIs transmitted (possibly across multiple PDSCH sets) for a particular UE or a particular HARQ-PUCCH process up to the current time. The combination of the counter DAI / total DAI and the cyclic DAI can avoid the ambiguity of the payload size of the HARQ feedback, especially in a single carrier deployment where there is no total DAI.

[0063] Figure 2 shows an example for determining the payload size of HARQ feedback based on the proposed indication in DCI. In this example, PDSCH is transmitted in slots n, n+1, n+3, n+4, n+6, and n+7, and ACK / NACK is fed back in slots n+2, n+5, and n+8. In addition, PDSCH in slots n and n+1 forms PDSCH set 1, PDSCH in slots n+3 and n+4 forms PDSCH set 2, and PDSCH in slots n+6 and n+7 forms PDSCH set 3. The reference symbol (i, j) in each slot shown in Figure 2 represents the counter DAI i and cyclic DAI j of the current slot. In other words, (i, j) means that it is the i-th DCI transmitted in the current PDSCH set and the j-th DCI transmitted to the UE.

[0064] In the above example, even if two ACK / NACK bits for PDSCH in slots n and n+1 are correctly transmitted in slot n+2, DCI in slot n+4 is not detected by mistake, and ACK / NACK in slot n+5 is not transmitted due to LBT failure, based on the DAI of the received DCI, the UE can determine to transmit a total of four ACK / NACK bits in slot n+8. In particular, based on the cyclic DAI of the DCI received in slots n+3, n+6, and n+7 (i.e., 2, 4, 5), the UE can know that one PDSCH transmission between cyclic DAI=2 and cyclic DAI=4 is not detected by mistake, and a total of four PDSCHs are transmitted.

[0065] Note that the cyclic DAI means that if the cumulative number of scheduling messages transmitted exceeds the maximum number that can be represented by the cyclic DAI, the number is reset to 0. For example, the cyclic DAI is 2 bits and has values ​​0, 1, 2, or 3, and when a total of 6 DCIs are transmitted, the cyclic DAI is set to a value of 1. In some embodiments, the cyclic DAI may be indicated per UE (which may be identified by a cell Radio Network Temporary Identity (C-RNTI)) or per HARQ-PUCCH process of the UE. In some embodiments, the cyclic DAI is reset when the HARQ feedback is successfully received by the gNB.

[0066] For communication systems such as NR-U, PUCCH transmission carrying ACK / NACK feedback may be blocked or fail due to LBT failure. In some scenarios, the probability of LBT failure is higher than the probability of DCI missed detection. Therefore, retransmission of PUCCH is beneficial in NR-U systems. If PUCCH cannot be retransmitted, the gNB needs to treat the corresponding PDSCH as NACK and retransmit the PDSCH, which is inefficient.

[0067] A failed PUCCH retransmission may use orthogonal resources, i.e., different resources than other transmissions. Alternatively or additionally, in some embodiments, a PUCCH retransmission may be performed by combining the blocked ACK / NACK bits with new ACK / NACK bits and transmitting the combined bits in the resource of the new ACK / NACK bits. That is, the blocked ACK / NACK bits may be transmitted together with the new ACK / NACK bits using the resource of the new ACK / NACK bits.

[0068] The PUCCH retransmission may be automatically determined by the UE, for example based on the result of the LBT. However, such automatic PUCCH retransmission may cause error diffusion in some scenarios. In some embodiments, it is proposed to add an additional field to the DCI to indicate whether a previous PUCCH has been detected, thereby assisting the UE in deciding whether to perform a PUCCH retransmission.

[0069] The inventors of the present application have found that due to processing delays, the DCI may not be able to indicate the detection result of the previous PUCCH. To improve the HARQ feedback in such cases, the concept of HARQ-PUCCH process ID is proposed in some embodiments. The HARQ-PUCCH process ID indicates an identifier of the HARQ PUCCH process and may be included in the DCI. This new field of the DCI (potentially together with other indications of PUCCH retransmission) allows the UE to retransmit only HARQ-ACK bits with the same HARQ-PUCCH process ID in the next PUCCH transmission opportunity. In some embodiments, the maximum number of HARQ-PUCCH processes is determined by the maximum number of newly indicated PUCCH opportunities between the PDCCH where the DCI is detected and the indication of the completion (success or failure) of the corresponding PUCCH indicated by that DCI. In some embodiments, the maximum number of HARQ-PUCCH processes may be 1. In this case, the HARQ-PUCCH process ID is not required. However, some limitations on the HARQ feedback are necessary, e.g., the UE is not expected to indicate a new PUCCH opportunity before the base station indicates completion (success or failure) of PUCCH transmission on an existing PUCCH opportunity, which means that in some embodiments, the base station's (e.g., gNB) indication of PUCCH completion, rather than the UE's transmission time of that PUCCH, is considered the end point of the PUCCH-HARQ process for counting.

[0070] FIG. 3 shows an example for determining the ACK / NACK bits to retransmit based on the proposed HARQ-PUCCH process ID.

[0071] In this example, ACK / NACK for HARQ PUCCH ID 0 is transmitted in slots n and n+1, but the ACK / NACK transmission in slot n+1 fails, e.g., due to LBT failure. ACK / NACK for HARQ PUCCH ID 1 is transmitted in slots n+2 and n+3. If the ACK / NACK in slot n+3 is not detected, the gNB indicates HARQ PUCCH process ID 0 to the UE, letting the UE know that slot n+1 needs to be retransmitted, otherwise the UE cannot know whether the PUCCH in slot n+1 or n+3 needs to be retransmitted.

[0072] Alternatively or additionally, in some embodiments, a concept of PUCCH resource set group is put forward to indicate the retransmission performance of HARQ feedback, thereby solving the problem caused by PUCCH and PDSCH missed detection. For example, a three-dimensional (3D) indication of PUCCH resources for HARQ feedback is proposed. As shown in FIG. 4, the 3D indication includes a resource set group indication, a resource set indication, and a resource indicator. A resource set group may include one or more resource sets, and a resource set may include one or more feedback resources (e.g., PUCCH resources). The indication of PUCCH resource set group is a new dimension proposed to select PUCCH resources, for example, based on the result of LBT. Generally, when HARQ feedback is transmitted / retransmitted for the nth time, a PUCCH resource from resource set group n is selected, where n is a positive integer. For example, if a PUCCH transmission carrying an ACK / NACK bit fails twice due to an LBT failure, when the UE retransmits the ACK / NACK bit for the third time, it will select resources from the third PUCCH resource set group to indicate that this is the third retransmission. Correspondingly, upon detecting a PUCCH in the third resource set group, the gNB will know that this is the third retransmission and can determine the PDSCH associated with the ACK / NACK feedback, i.e., the PDSCH to which the ACK / NACK is fed back.

[0073] Within the selected resource set group, a resource set may be selected according to the payload of the ACK / NACK to be fed back, and in addition, the PUCCH resource within the selected resource set may be determined for PUCCH transmission based on an indication included in the DCI of the corresponding PDSCH.

[0074] In some embodiments, if the nth PUCCH transmission / retransmission and the mth PUCCH transmission / retransmission are assigned the same PUCCH resource indicator, then the ACK / NACK bits of the nth and mth PUCCH transmission / retransmission may be multiplexed together. In addition, the UE may select a PUCCH resource set for the combined transmission based on the total length of the combined ACK / NACB bits.

[0075] FIG. 5 shows an example for determining PUCCH resources for ACK / NACK feedback based on the concept of PUCCH resource set group, and the following Table 1 shows an example of resource selection rule. Table 1 TIFF0007601127000001.tif53148

[0076] In this example, assume that the DCI of PDSCH in slot n, n+1 assigns the same PUCCH resource indicator for HARQ feedback. Then, according to Table 1, if the ACK / NACK of PDSCH in slot n is transmitted in slot n+2, resource 0 of group 1 is selected because it is the first transmission of ACK / NACK. If the ACK / NACK of PDSCH in slot n+1 is also transmitted in slot n+2, resource 1 of group 1 is selected because it is multiplexed with the ACK / NACK of PDSCH in slot n, and it is the first transmission and the payload size is 2. If the ACK / NACK of PDSCH in slot n is transmitted in slot n+5, resource 2 of group 2 is selected because it is the second retransmission. If the ACK / NACK of PDSCH in slot n+1 is also transmitted in slot n+5, resource 3 of group 1 is selected because it is multiplexed with the ACK / NACK of PDSCH in slot n, and it is the second transmission and the payload size is 2. The ACK / NACK resources associated with the PDSCHs in slots n+3 and n+4 are derived in a similar manner.

[0077] An alternative way to avoid the imprecise problem due to DCI missed detection or PUCCH retransmission is to use a static HARQ codebook, which means that the payload size of the HARQ feedback transmission is pre-determined, e.g. based on an association of PDSCH timeslots with feedback timeslots, where the association / timing is configured, e.g. via RRC signaling.

[0078] For a static HARQ codebook, for a UE receiving a PDSCH in slot n with a DCI indicating a feedback slot indexed by n+k, if the UE reports HARQ-ACK information for PDSCH reception in a slot other than slot n+k, the value of each corresponding HARQ-ACK information bit is set to NACK, as specified in 3GPP. Such a coding method reduces the detection complexity at the gNB side and provides good transmission performance. However, the inventors of the present disclosure have found that such a coding method does not provide redundancy and is not suitable for PUCCH transmission in unlicensed bands, where the PUCCH may be blocked due to LBT failure, for example.

[0079] Therefore, in some embodiments, we propose to configure two types of coding, which may be called Type A and Type B, for the static HARQ codebook.

[0080] As specified in 3GPP, for Type A coding, if the UE reports HARQ-ACK information for PDSCH reception in a slot other than slot n+k, the UE sets the value of each corresponding HARQ-ACK information bit to NACK.

[0081] In contrast, in Type B coding, even if the UE reports HARQ-ACK information for PDSCH reception in a slot other than slot n+k (the feedback slot indicated by the DCI of the corresponding PDSCH), the UE sets the value of each corresponding HARQ-ACK information bit to its actual value, i.e., a value determined based on the detection result of the PDSCH.

[0082] The type of coding used for the HARQ feedback (i.e., Type A or Type B) may be configured by a network device (e.g., a gNB).

[0083] Figure 6 shows a schematic example of Type A and Type B for HARQ feedback. As shown in Figure 6, HARQ feedback for PDSCH set in slots 601-605 may be transmitted in slot 606 according to pre-determined or configured timing / association via RRC signaling, but only DCI of PDSCH in slot 603 indicates that ACK / NACK is fed back in slot 606. And, in slot 606, five ACK / NACK bits of slots 601-605 are transmitted, but only ACK / NACK bit of slot 603 is set to actual value and other bits are set to NACK according to Type A coding. Similarly, HARQ feedback for PDSCH set of slots 602-605 may be transmitted in slot 607 according to a predefined timing / association, but if only DCI of PDSCH in slot 605 indicates that ACK / NACK is fed back in slot 607, then in slot 607, four ACK / NACK bits of slots 602-605 are transmitted, but only ACK / NACK bit of slot 605 is set to actual value and other bits are set to NACK. Type A coding has good transmission performance but does not provide redundant information, so if PUCCH in slot 606 is not detected by mistake, the value of HARQ feedback for slot 603 is not known to the network device.

[0084] The above problem can be solved by type B coding. In type B coding, HARQ feedback for a PDSCH set in slots 601-605 is transmitted in slot 606, and all ACK / NACK bits in slots 601-605 are set to their actual values. Similarly, HARQ feedback for one PDSCH set in slots 602-605 is transmitted in slot 607, and all ACK / NACK bits are set to their actual values. This means that feedback for slots 602-605 is transmitted in both slot 606 and slot 607. In such a case, even if the PUCCH in slot 606 is not detected due to a miss, the network device can recover the HARQ feedback for slots 602-605 from the HARQ feedback in slot 607.

[0085] Furthermore, in case of HARQ feedback based on a static codebook, the gNB may trigger transmission or retransmission of HARQ feedback by indicating in the DCI the timing or offset of the PUCCH transmission relative to the slot in which the DCI is transmitted.

[0086] Reference is now made to Figure 7, which illustrates a flowchart of an example method 700 of HARQ feedback. The method 700 may be implemented by a network device, for example the network device 101 illustrated in Figure 1. For convenience of explanation, the method 700 will be described below with reference to the network device 101 and the communication network 100 illustrated in Figure 1. However, embodiments of the present disclosure are not limited thereto. For example, the method may be implemented by a terminal device involved in D2D communication in some scenarios.

[0087] As shown in FIG. 7, in block 710, the network device 101 transmits a scheduling message to a terminal device, for example, one terminal device 102 in FIG. 1. The scheduling message may include, for example, DCI. In addition, the scheduling message includes information regarding HARQ feedback. The information regarding HARQ feedback indicates a process ID (e.g., HARQ PUCCH process ID) for HARQ feedback and / or a cumulative number of scheduling messages transmitted for the terminal device or process ID. In some embodiments, the cumulative number of scheduling messages may be in the form of a cyclic DAI, as shown in FIG. 2.

[0088] The process ID and / or cyclic DAI for the HARQ feedback facilitates the terminal device 102 to determine the PDSCH for which ACK / NACK feedback is required, thereby avoiding the ambiguity problem regarding the payload size of the HARQ feedback. Some examples for determining the payload size of the HARQ feedback are described with reference to FIGS.

[0089] In some embodiments, the scheduling message, e.g., DCI, may further include one or more of an indication of the total number of scheduling messages transmitted on a given transmission set (e.g., PDSCH set) associated to the same HARQ feedback timeslot (e.g., in the form of a counter DAI as shown in FIG. 2), an indication of the total number of scheduling messages to be transmitted on a given transmission set (e.g., PDSCH set) associated to the same HARQ feedback timeslot (e.g., in the form of a sum DAI), and an indication to provide new HARQ feedback.

[0090] The indication to provide new HARQ feedback may be in the form of a New Feedback Indicator (NFI), which may be a toggle bit. That is, the NFI of the DCI may indicate whether the expected HARQ-ACK feedback from the UE was correctly received by the gNB. For example, if the NFI bit is not toggled, it means that no HARQ-ACK opportunity was received since the NFI bit was last toggled. In this case, the UE may automatically include the HARQ-ACK bit that was not correctly received in the next reporting opportunity, i.e., retransmit the HARQ-ACK bit. On the other hand, if the NFI bit is toggled, it means that a HARQ-ACK opportunity was received by the gNB since the bit was last toggled, so there is no need to retransmit the HARQ-ACK bit.

[0091] In some embodiments, to facilitate HARQ feedback, a combination of one or more of the cycle DAI, HARQ PUCCH ID, and NFI may be transmitted in a scheduling message to the terminal device 102 at block 710. In addition, the combination may be transmitted along with other information related to the HARQ feedback, such as a counter DAI and / or a total DAI.

[0092] At block 720, the network device 101 transmits data to the terminal device 102 according to the scheduling message. As a non-limiting example, the data is transmitted via a PDSCH.

[0093] In block 730, the network device 101 receives HARQ feedback from the terminal device 102, and in block 740, the network device 101 controls a subsequent transmission or retransmission based on the received HARQ feedback. The operation of controlling the transmission / retransmission based on the HARQ feedback can be performed similarly to that in current communication systems. For example, when a NACK is received for a data transmission, the network device 101 can retransmit the data transmission accordingly. When an ACK is received for a data transmission, the network device 101 can prevent the retransmission of the data.

[0094] 8 shows a flowchart of another example method 800 of HARQ feedback. The method 800 may be implemented by a network device, for example, the network device 101 shown in FIG. 1. The method 800 may be implemented individually or in combination with the method 700. Also, for convenience of explanation, the method 800 will be described below with reference to the network device 101 and the communication network 100 shown in FIG. 1. However, the embodiments of the present disclosure are not limited thereto. For example, the method may be implemented by a terminal device involved in D2D communication in some scenarios.

[0095] As shown in Figure 8, in block 810, the network device 101 transmits a scheduling message to the terminal device 102. The scheduling message may be the same as or different from the scheduling message described with reference to Figure 7. As a non-limiting example, the scheduling message may be in the form of a DCI.

[0096] The network device 101 transmits data to the terminal device 102 according to the scheduling message, for example, via a PDSCH, in block 820 , and detects HARQ feedback from the terminal device 102 in block 830 .

[0097] In block 840, the network device 101 determines a resource ID of the resource for which HARQ feedback was detected. The resource ID includes an identifier of a resource set group associated with the resource. A resource set group includes one or more resource sets, and a resource set includes one or more resources. That is, a resource can be identified via a 3D ID as shown in FIG. 4.

[0098] At block 850, the network device 101 controls a subsequent transmission or retransmission based on the received HARQ feedback and the resource ID. As a non-limiting example, if the HARQ feedback is detected in the i-th resource set group, the network device 101 may determine that the received HARQ feedback is the i-th retransmission. The network device 101 may then determine a previous data transmission associated with the i-th retransmission of the HARQ feedback and control the retransmission of the previous data transmission based on the received HARQ feedback. If the received HARQ feedback is an ACK, the network device 101 prevents the retransmission of the previous data transmission, and if the received HARQ feedback is a NACK, the network device 101 performs a retransmission of the previous data transmission. For example, in the example shown in FIG. 5, if a NACK is detected in resource 2 belonging to resource set group 2, the network device 101 may determine that it is the second retransmission of the NACK for the PDSCH in slot n. As a result, the network device 101 retransmits the PDSCH previously transmitted in slot n.

[0099] 9 shows a flowchart of another example method 900 of HARQ feedback. The method 900 may be implemented by a network device, for example, the network device 101 shown in FIG. 1. The method 900 may be implemented individually or in combination with one or more of the methods 700 and 800. For convenience of explanation, the method 900 is described below with reference to the network device 101 and the communication network 100 shown in FIG. 1. However, embodiments of the present disclosure are not limited thereto. For example, the method may be implemented by a terminal device involved in D2D communication in some scenarios.

[0100] 9, in block 910, the network device 101 transmits a coding configuration for HARQ feedback to the terminal device 102. The coding configuration indicates a type of encoding for the static HARQ codebook. As a non-limiting example, the coding configuration may be transmitted via RRC signaling or system information.

[0101] At block 920, the network device 101 transmits data to the terminal device 102 and at block 930 detects HARQ feedback for the data from the terminal device 102 based on the indicated type of encoding.

[0102] In some embodiments, the type of encoding may include one of Type A and Type B encoding, as described above with reference to Figure 6. For purposes of illustration, assume that the network device 101 transmits data along with a scheduling message (e.g., DCI) to the terminal device 102 in timeslot n, and the scheduling message indicates that HARQ feedback is to be provided by the terminal device 102 in timeslot n+k, where both n and k are non-negative integers, and Type A is indicated in block 910. If HARQ feedback for the data is received in timeslot n+k, the network device 101 decodes the HARQ feedback, whereas if HARQ feedback for the data is detected in a timeslot other than timeslot n+k, the network device 101 interprets the received HARQ feedback bits as a NACK. In contrast, when coding type B is indicated in block 910, the network device 101 decodes the HARQ feedback regardless of whether it is detected in time slot n+k or another time slot. Type B coding increases the redundancy of the HARQ feedback.

[0103] In block 940, the network device 101 controls subsequent transmissions or retransmissions based on the detected HARQ feedback. In some embodiments, operations similar to those used in current HARQ mechanisms may be implemented in block 940.

[0104] 10 shows a flowchart of an example method 1000 of HARQ feedback. The method 1000 may be implemented by a terminal device, for example, one terminal device 102 shown in FIG. 1. For convenience of explanation, the method 1000 will be described below with reference to the terminal device 102 and the communication network 100 shown in FIG. 1. However, the embodiments of the present disclosure are not limited thereto.

[0105] 10, in block 1010, the terminal device 102 receives a scheduling message from the network device 101. The scheduling message includes information about the HARQ feedback, where the information about the HARQ feedback indicates at least one of a process ID for the HARQ feedback and a cumulative number of scheduling messages sent for the terminal device or process ID.

[0106] In some embodiments, the scheduling message may be in the form of a DCI. In some embodiments, the scheduling message may be the same as that described with reference to method 700, and therefore the relevant description of method 700 also applies here.

[0107] In some embodiments, the process ID for HARQ feedback may be in the form of a HARQ PUCCH process ID, and the cumulative number of scheduling messages may be in the form of a cycle DAI.

[0108] In some embodiments, the scheduling message may further include one or more of an indication of the total number of scheduling messages transmitted on a given transmission set (e.g., PDSCH set) associated with the same HARQ feedback timeslot (e.g., a counter DAI), an indication of the total number of scheduling messages to be transmitted on a given transmission set (e.g., PDSCH set) associated with the same HARQ feedback timeslot (e.g., a total DAI), and / or an indication to provide new HARQ feedback (e.g., an NFI).

[0109] In block 1020, the terminal device 102 detects data from the network device 101 according to a scheduling message (e.g., DCI), and in block 1030, the terminal device 102 transmits HARQ feedback to the network device 101 based on information regarding the HARQ feedback.

[0110] In some embodiments, the information regarding the HARQ feedback may include a cyclic DAI indicating a cumulative number of scheduling messages (e.g., DCI) transmitted for a terminal device or process ID (possibly across multiple PDSCH sets). In such an embodiment, in block 1030, the terminal device 102 may determine a total number of bits transmitted for the HARQ feedback based on the cyclic DAI and transmit the HARQ feedback having the determined total number of bits to the network device 101.

[0111] In some embodiments, the information regarding the HARQ feedback may include a HARQ PUCCH process ID. In such a case, the terminal device 102 may determine one or more previous downlink data transmissions associated with the process ID and transmit HARQ feedback for the detected data to the network device 101 along with HARQ feedback for the one or more previous downlink data transmissions.

[0112] 11 shows a flowchart of another exemplary method 1100 of HARQ feedback. The method 1100 may be implemented by a terminal device, for example, one terminal device 102 shown in FIG. 1. It should be noted that the method 1100 may be implemented individually or in combination with the method 1000. For convenience of explanation, the method 1100 will be described below with reference to the terminal device 102 and the communication network 100 shown in FIG. 1. However, the embodiments of the present disclosure are not limited thereto.

[0113] As shown in Figure 11, in block 1110, the terminal device 102 receives data from the network device 101. In the HARQ mechanism, the terminal device 102 needs to provide feedback for the received data. However, in some scenarios, for example, in an NR-U communication system, the feedback may be blocked or fail due to an LBT failure in an unlicensed band. Therefore, in some cases, the terminal device 102 may decide to retransmit the HARQ feedback.

[0114] If the terminal device 102 determines to retransmit feedback for the data for the i-th time, then in block 1120, the terminal device 102 selects a resource from the i-th resource set group, where i is a positive integer. The resource set group includes one or more resource sets, and the resource set includes one or more feedback resources.

[0115] In block 1130, the terminal device 102 retransmits the feedback for the data on the selected resource. In this way, the terminal device 102 can implicitly indicate the number of retransmissions performed for the HARQ feedback to the network device 101 to avoid ambiguity problems on the network device side.

[0116] 12 shows a flowchart of another exemplary method 1200 of HARQ feedback. The method 1200 may be implemented by a terminal device, for example, one terminal device 102 shown in FIG. 1. It should be noted that the method 1200 may be implemented individually or in combination with one or more of the methods 1000 and 1100. For convenience of explanation, the method 1200 will be described below with reference to the terminal device 102 and the communication network 100 shown in FIG. 1. However, the embodiments of the present disclosure are not limited thereto.

[0117] 12, in block 1210, the terminal device 102 receives a coding configuration for HARQ feedback from the network device 101. The coding configuration indicates a type of coding for the static HARQ codebook. In some embodiments, the indicated type of coding includes type A or type B coding. For example, but not limited to, the coding configuration may be received via RRC signaling or system information.

[0118] In block 1220, the terminal device 102 receives data from the network device 101, and in block 1230, the terminal device 102 generates HARQ feedback for the data based on the coding configuration.

[0119] For example, in block 1220, the terminal device 102 may receive data along with a scheduling message (e.g., DCI) from the network device 101 in time slot n. The scheduling message indicates that HARQ feedback is to be provided by the terminal device 102 in time slot n+k, where n and k are both non-negative integers.

[0120] In one embodiment where type A coding is configured in block 1210, if the terminal device 102 determines to transmit HARQ feedback for the data in time slot n+k, then in block 1230 the terminal device 102 generates HARQ feedback bits dependent on the detection result of the data transmission received in time slot n. On the other hand, if the terminal device 102 determines to transmit HARQ feedback for the data in a time slot other than time slot n+k, then in block 1230 the terminal device 102 generates a NACK bit for the data transmission.

[0121] In some embodiments in which type B coding is configured in block 1210, in block 1230, the terminal device 102 generates HARQ feedback bits depending on the detection result of the data transmission received in time slot n, regardless of whether the HARQ feedback is transmitted in time slot n+k or another slot.

[0122] In block 1240, the terminal device 102 transmits the generated HARQ feedback to the network device 101. As described with reference to Figure 6, Type B encoding allows the terminal device 102 to transmit the HARQ feedback for the PDSCH multiple times, providing redundancy so that the network device 101 can recover the HARQ feedback even if one transmission fails.

[0123] From the above embodiment, the UE may be configured to use Type A or Type B encoding for HARQ feedback in response to a PDSCH received in slot n, and when the UE reports HARQ-ACK information for PDSCH reception in a slot other than slot n+k, the UE sets the value of each corresponding HARQ-ACK information bit to NACK when Type A is configured, and sets the value of each corresponding HARQ-ACK information bit to HARQ-ACK information bit when Type B is configured, and the value of k may be indicated in the DCI associated with the PDSCH in slot n.

[0124] FIG. 13 illustrates a simplified block diagram of an apparatus 1300 that may be embodied as or comprised in a terminal device (eg, terminal device 102 shown in FIG. 1) or a network device (eg, network device 101 shown in FIG. 1).

[0125] The apparatus 1300 comprises at least one processor 1311, such as a data processor (DP), and at least one memory (MEM) 1312 connected to the processor 1311. The apparatus 1300 may further comprise a transmitter TX and a receiver RX 1313 connected to the processor 1311, the transmitter TX and the receiver RX 1313 operable to communicatively connect to other apparatuses. The MEM 1312 stores programs and computer program code 1314. The at least one memory 1312 and the computer program code 1314 are configured to cause the at least one processor 1311 to cause the apparatus 1300 to perform at least according to any of the embodiments of the present disclosure, e.g., methods 700-1200.

[0126] The combination of the at least one processor 1311 and the at least one MEM 1312 may form a processing means configured to perform various embodiments of the present disclosure.

[0127] Various embodiments of the present disclosure may be implemented by a computer program executable by the processor 1311, software, firmware, hardware, or a combination thereof.

[0128] The MEM1312 may be of any type suitable for the local technical environment and may be implemented using any suitable data storage technology, such as, by way of non-limiting example, semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed and removable memory.

[0129] The processor 1311 may be of any type suitable for the local technical environment and may include, by way of non-limiting examples, one or more of a general purpose computer, a special purpose computer, a microprocessor, a digital signal processor (DSP), and a processor based on a multi-core processor architecture.

[0130] The present disclosure may further provide a carrier containing a computer program as described above. The carrier includes a computer-readable storage medium and a transmission medium. The computer-readable storage medium may be, for example, an optical compact disc, or an electronic memory device such as a random access memory (RAM), a read only memory (ROM), a flash memory, a magnetic tape, a CD-ROM, a DVD, a Blue-ray disc, etc. The transmission medium may include, for example, an electrical, optical, radio, acoustic, or other form of propagated signal, such as a carrier wave, an infrared signal, etc.

[0131] The techniques described herein may be implemented by various means. Thus, an apparatus implementing one or more functions of the corresponding apparatus described in the embodiments may include not only conventional means, but also means for implementing one or more functions of the corresponding apparatus, and may include separate means for each separate function, or may include means configured to implement two or more functions. For example, these techniques may be implemented in hardware (e.g., circuits or processors), firmware, software, or a combination thereof. In the case of firmware or software, it may be implemented via modules (e.g., procedures, functions, etc.) that perform the functions described herein.

[0132] Some exemplary embodiments herein have been described above with reference to block diagrams and flowchart diagrams of methods and apparatus. It will be understood that each block of the block diagrams and flowchart diagrams, and combinations of blocks in the block diagrams and flowchart diagrams, respectively, can be implemented by various means including computer program instructions. These computer program instructions may be loaded into a general purpose computer, a special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions executed by the computer or other programmable data processing apparatus form means for performing the functions identified in the flowchart blocks.

[0133] Although the specification contains many specific implementation details, these should not be construed as limitations on any implementation or claims, but rather as descriptions of features specific to a particular embodiment of a particular implementation. Certain features described in the context of separate embodiments herein may also be implemented in combination in a single embodiment. Conversely, various features described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable subcombination. Furthermore, even if features are described above as operating in a particular combination and are initially claimed as such, one or more features from a claimed combination may, in some cases, be excluded from the combination, and the claimed combination may be directed to a subcombination or a variation of the subcombination.

[0134] It is obvious to those skilled in the art that with the advancement of technology, the concept of the present invention can be implemented in various ways. The above embodiments are provided to illustrate, not to limit, the present disclosure, and as those skilled in the art can easily understand, they can be modified and changed without departing from the intent and scope of the present disclosure. Such modifications and changes are considered to be within the scope of the present disclosure and the scope of the appended claims. The protection scope of the present disclosure is defined by the scope of the appended claims.

[0135] Some abbreviations and their corresponding terms used in this disclosure are listed below. 3GPP 3rd Generation Partnership Project LTE long-term evolution NR New Radio NR-U NR-unlicensed LAA LTE Licensed Assisted Access HARQ Hybrid Automatic Repeat Request PUCCH Physical Uplink Control Channel PUSCH Physical Uplink Shared Channel PDSCH Physical Downlink Shared Channel DCI Downlink Control Indicator UCI Uplink Control Information ACK Acknowledgement NACK Negative acknowledgment CCA Clear Channel Assessment LBT Listen Before Talk COT Channel Occupancy Time C-RNTI Cell Radio Network Temporary Identifier

Claims

1. 1. A method for wireless communication, comprising: Sending a scheduling message to a terminal device; transmitting data to the terminal device according to the scheduling message; Detecting hybrid automatic repeat request (HARQ) feedback from the terminal device; determining a resource ID of a resource for which the HARQ feedback is detected; and controlling a subsequent transmission or retransmission based on the HARQ feedback and the resource ID; Equipped with the resource ID includes an identifier of a resource set group associated with the resource, the resource set group including one or more resource sets, a resource set including one or more resources; method.

2. Controlling a subsequent transmission or retransmission based on the HARQ feedback and the resource ID, determining, in response to the identifier of the resource set group indicating an i-th resource set group, that the HARQ feedback is an i-th retransmission of a HARQ feedback; determining a previous data transmission associated with the i-th retransmission of the HARQ feedback; and controlling a retransmission of the previous data transmission based on the HARQ feedback; and Including, The method of claim 1.

3. Controlling a retransmission of the previous data transmission based on the HARQ feedback includes: in response to the HARQ feedback being an acknowledgment (ACK), inhibiting a retransmission of the previous data transmission; in response to the HARQ feedback being a negative acknowledgment (NACK), performing a retransmission of the previous data transmission; Including, The method of claim 2.

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