Method and apparatus for configuring HARQ-ACK feedback

Abstract

The present disclosure describes methods, systems, and devices for configuring hybrid automatic repeat request acknowledgement (HARQ‑ACK) feedback for physical downlink shared channel (PDSCH) transmissions. The method includes: receiving, by a user equipment (UE), radio resource control (RRC) parameters for configuring an enhanced dynamic HARQ‑ACK feedback mode; and receiving, by the UE, first downlink control information (DCI) including a first K. The first DCI corresponds to a first PDSCH. The method also includes: receiving, by the UE, a second DCI for a second PDSCH, the second DCI including a second K having an applicable value; and transmitting, by the UE, enhanced dynamic HARQ‑ACK feedback according to a preset rule.

Description

Technical Field

[0001] The present disclosure relates generally to wireless communications and, more particularly, to methods and apparatus for configuring Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK) feedback. Background Art

[0002] Wireless communication technology is pushing the world towards an increasingly interconnected and networked society. High-speed, low-latency wireless communications rely on efficient network resource management and allocation between user equipment and radio access network nodes (including but not limited to wireless base stations). The new generation of networks is expected to provide high-speed, low-latency and ultra-reliable communication capabilities and meet the requirements of different industries and users. Ultra-reliable low-latency communication (URLLC) can provide communication with high reliability and low latency between user equipment and radio access network nodes. URLLC can be supported on licensed frequency carriers and / or unlicensed frequency carriers. There are some issues and problems associated with transmitting feedback information, for example, how to improve the performance of transmitting feedback information when the user equipment (UE) needs to configure hybrid automatic repeat request acknowledgment (HARQ-ACK) feedback. The present disclosure can solve at least some problems associated with existing systems to improve the performance of wireless communications. Summary of the Invention

[0003] This document relates to methods, systems, and devices for wireless communications, and more particularly, to methods, systems, and devices for configuring Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK) feedback.

[0004] In one embodiment, the present disclosure describes a method for wireless communication. The method includes configuring hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback for a physical downlink shared channel (PDSCH) transmission by: receiving, by a user equipment (UE), radio resource control (RRC) parameters for configuring an enhanced dynamic HARQ-ACK feedback mode; receiving, by the UE, first downlink control information (DCI) including a first K, the first DCI corresponding to a first PDSCH; receiving, by the UE, a second DCI for a second PDSCH, the second DCI including a second K having an applicable value; and transmitting, by the UE, enhanced dynamic HARQ-ACK feedback according to a preset rule.

[0005] In one embodiment, the present disclosure describes a method for wireless communication. The method includes configuring hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback for a physical downlink shared channel (PDSCH) transmission by: sending, by a radio access network (RAN), to a user equipment (UE), radio resource control (RRC) parameters for configuring an enhanced dynamic HARQ-ACK feedback mode; sending, by the RAN, to the UE, first downlink control information (DCI) including a first K, the first DCI corresponding to a first PDSCH; sending, by the RAN, to the UE, a second DCI for a second PDSCH, the second DCI including a second K having an applicable value; and receiving, by the RAN, from the UE, the enhanced dynamic HARQ-ACK feedback according to a preset rule.

[0006] In some other embodiments, an apparatus for wireless communication may include a memory storing instructions and a processing circuit in communication with the memory. When the processing circuit executes the instructions, the processing circuit is configured to perform the above method.

[0007] In some other embodiments, a device for wireless communication may include a memory storing instructions and a processing circuit in communication with the memory. When the processing circuit executes the instructions, the processing circuit is configured to perform the above method.

[0008] In some other embodiments, a computer-readable medium includes instructions that, when executed by a computer, cause the computer to perform the above-described method.

[0009] The above and other aspects and their implementations are described in more detail in the drawings, description and claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 An example of a wireless communication system is shown.

[0011] Figure 2 An example of a wireless network node is shown.

[0012] Figure 3 An example of a user device is shown.

[0013] Figure 4 A flow chart of a method for wireless communication is shown.

[0014] Figure 5A A schematic diagram of a method for wireless communication is shown.

[0015] Figure 5B A schematic diagram of a method for wireless communication is shown.

[0016] Figure 5C A schematic diagram of a method for wireless communication is shown.

[0017] Figure 6A A schematic diagram of a method for wireless communication is shown.

[0018] Figure 6B A schematic diagram of a method for wireless communication is shown.

[0019] Figure 7 A schematic diagram of a method for wireless communication is shown. DETAILED DESCRIPTION

[0020] The present disclosure will now be described in detail hereinafter with reference to the accompanying drawings, which form a part hereof and show by way of illustration specific examples of embodiments. However, it is noted that the present disclosure may be embodied in a variety of different forms, and therefore, the subject matter encompassed or claimed is not intended to be construed as limited to any of the embodiments described below.

[0021] Throughout the specification and claims, terms may have nuanced meanings suggested or implied by the context, beyond their explicitly stated meanings. Likewise, the phrases "in one embodiment" or "in some embodiments" as used herein do not necessarily refer to the same embodiment, and the phrases "in another embodiment" or "in other embodiments" as used herein do not necessarily refer to different embodiments. The phrases "in one implementation" or "in some implementations" as used herein do not necessarily refer to the same implementation, and the phrases "in another implementation" or "in other implementations" as used herein do not necessarily refer to different implementations. For example, it is intended that the claimed subject matter include all or part of a combination of exemplary embodiments or implementations.

[0022] In general, terms can be understood at least in part from their usage in the context. For example, terms such as "and," "or," or "and / or" as used herein can include multiple meanings that can depend at least in part on the context in which such terms are used. Typically, "or" when used in an association list (such as A, B, or C) means A, B, and C (used here in an inclusive sense) as well as A, B, or C (used here in an exclusive sense). In addition, depending at least in part on the context, the terms "one or more" or "at least one" as used herein can be used to describe any feature, structure, or characteristic in a singular sense, or can be used to describe a combination of features, structures, or characteristics in a plural sense. Similarly, depending at least in part on the context, terms such as "a," "an," or "the" can also be understood to convey singular or plural usage. In addition, the terms "based on" or "determined by..." can be understood to not necessarily be intended to convey a set of exclusive factors, but rather, depending at least in part on the context, can allow for the presence of other factors that are not necessarily explicitly described.

[0023] The present disclosure describes methods and apparatus for configuring Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK) feedback.

[0024] Next generation (NG) or fifth generation (5G) wireless communications can provide a range of capabilities, from fast downloads to support for real-time low-latency communications. Next generation (NG) mobile communication systems are moving the world towards an increasingly interconnected and networked society. High-speed, low-latency wireless communications rely on efficient network resource management and allocation between user equipment and radio access network nodes (including but not limited to radio base stations). The next generation network is expected to provide high-speed, low-latency and ultra-reliable communication capabilities and meet the requirements of different industries and users. Ultra-reliable low-latency communication (URLLC) can provide communication with high reliability and low latency between user equipment and radio access network nodes. In order to increase bandwidth, shorten latency and / or increase speed, wireless communications can be carried out in licensed bands and / or new radio unlicensed (NR-U) bands.

[0025] In a fifth generation (5G) communication system on a licensed frequency carrier, a URLLC service may be configured with one or more sub-timeslots within a time slot. Each of the one or more sub-timeslots may be configured to transmit feedback information in order to reduce latency in the URLLC service on the licensed carrier. In a fifth generation (5G) communication system on an NR-U frequency carrier, there is a problem in that the time required to transmit feedback information increases, thereby increasing latency and deteriorating performance of the communication system on the NR-U carrier.

[0026] This disclosure describes various embodiments that address some of the above-mentioned issues.

[0027] Figure 1 A wireless communication system 100 is shown, comprising a core network (CN) 110, a radio access network (RAN) 130, and one or more user equipment (UE)s (152, 154, and 156). The RAN 130 may comprise a wireless network base station or a next-generation radio access network (NG-RAN) base station or node, which may comprise a nodeB (NB, e.g., gNB) in the context of mobile telecommunications. In one implementation, the core network 110 may comprise a 5G core network (5GC), and the interface 125 may comprise a next-generation (NG) interface.

[0028] refer to Figure 1, a first UE 152 may wirelessly receive downlink communications 142 from the RAN 130 and wirelessly send uplink communications 141 to the RAN 130. Similarly, a second UE 154 may wirelessly receive downlink communications 144 from the RAN 130 and wirelessly send uplink communications 143 to the RAN 130; and a third UE 156 may wirelessly receive downlink communications 146 from the RAN 130 and wirelessly send uplink communications 145 to the RAN 130. By way of example, and not limitation, downlink communications may include a physical downlink shared channel (PDSCH) or a physical downlink control channel (PDCCH), and uplink communications may include a physical uplink shared channel (PUSCH) or a physical uplink control channel (PUCCH). Downlink communications (142, 144, and / or 146) and / or uplink communications (141, 143, and / or 145) may be transmitted on a licensed frequency carrier or an NR-U frequency carrier.

[0029] When URLLC operates on a licensed carrier, the UE may be configured with more than one HARQ-ACK codebook through at least one radio resource control (RRC) parameter (e.g., but not limited to, pdsch-HARQ-ACK-Codebook-List-r16 and UCI-OnPUSCH-List-r16). When two HARQ-ACK codebooks are configured, the parameters for these HARQ-CACK codebooks (such as candidate k1 sets, PUCCH resource sets, and UCI-OnPUSCH) may be configured separately. The two HARQ-ACK codebooks may be transmitted in different PUCCH / PUSCHs dependently. When the transmission of these two codebooks occurs in the same time slot, the HARQ-ACK codebook of lower priority (e.g., priority index = 0) may be discarded.

[0030] Using unlicensed carriers to transmit data can improve the utilization of available transmission resources, thereby improving URLLC performance. There are some challenges in operating URLLC on unlicensed carriers. In low-latency wireless communications on unlicensed carriers, due to channel quality defects and fluctuations in communication resources, the transmitted wireless messages may be lost or damaged and cannot be corrected. For example, since channel access should be performed before data transmission, the device needs to perform a clear channel assessment (CCA) and obtain a successful result before data transmission. In some countries and regions, there are regulatory policies regarding the use of unlicensed spectrum. The device can perform a listen-before-talk (LBT) process (e.g., CCA) before sending data via the unlicensed carrier. For example, according to the channel access process, only devices with a successful CCA can send data on the unlicensed carrier.

[0031] Another issue can arise when URLLC operates in unlicensed carriers. When channel access failure occurs, the gNB / UE may not transmit data, and the receiver may not receive the data correctly. These incorrectly received messages may require retransmission, degrading latency and reliability. Therefore, a properly designed control mechanism for detecting and retransmitting lost or corrupted messages can help improve the efficiency of the radio access network, particularly for accessing unlicensed shared radio bands. To improve data transmission efficiency, channel access procedures and control signaling need to be considered, and the communication system can support fast and reliable data transmission, such as using unlicensed carriers to transmit URLLC uplink HARQ-ACK feedback.

[0032] For wireless transmissions in unlicensed carriers, an enhanced dynamic HARQ-ACK feedback scheme can be used to provide multiple transmission opportunities for ACK / NACK feedback. When the UE configures the enhanced dynamic feedback scheme, downlink control information (DCI) of a specific format (e.g., DCI format 1_1) may include three new bit fields. One bit field may be used for a PDSCH group index, which may be 1 bit or 2 bits. One bit field may be used for a new feedback indication (NFI). In one implementation, a toggled NFI may indicate that the ACK / NACK feedback information is correctly received. One bit field may be used for multiple requested PDSCH groups. In one implementation, if two PDSCH groups are requested at the same time, the HARQ-ACK codebooks of the two PDCCH groups may be transmitted on the same PUCCH / PUSCH. In another implementation, only two PDSCH groups are supported in NR-U.

[0033] This disclosure describes various embodiments for supporting URLLC transmissions on unlicensed bands and carriers and providing more transmission opportunities for HARQ-ACK feedback. Various embodiments include enhanced dynamic HARQ-ACK codebook modes supported by URLLC. This disclosure addresses some challenges when URLLC supports enhanced dynamic HARQ-ACK codebook feedback for unlicensed band operation, such as, but not limited to, how to combine the two different features of these two requirements, and / or how to achieve compatibility between NR-U HARQ design and URLLC enhancements.

[0034] Figure 2An exemplary radio access network or wireless communication base station 200 is shown. Base station 200 may include wireless transmission / reception (Tx / Rx) circuitry 208 for transmitting / receiving communications with one or more UEs and / or one or more other base stations. The base station may also include network interface circuitry 209 (e.g., fiber or wired interconnect, Ethernet, and / or other data transmission media / protocols) for enabling the base station to communicate with other base stations and / or a core network. Base station 200 may optionally include an input / output (I / O) interface 206 for communicating with operators and the like.

[0035] The base station may also include system circuitry 204. System circuitry 204 may include processor(s) 221 and / or memory 222. Memory 222 may include an operating system 224, instructions 226, and parameters 228. Instructions 226 may be configured for one or more processors 124 to perform base station functions. Parameters 228 may include parameters that support execution of instructions 226. For example, the parameters may include network protocol settings, bandwidth parameters, radio frequency mapping assignments, and / or other parameters.

[0036] Figure 3An exemplary user equipment (UE) 300 is shown. UE 300 may be a mobile device, such as a smartphone or a mobile communication module provided in a vehicle. UE 300 may include a communication interface 302, system circuitry 304, an input / output interface (I / O) 306, a display circuit 308, and a storage device 309. The display circuitry may include a user interface 310. System circuitry 304 may include any combination of hardware, software, firmware, or other logic / circuitry. System circuitry 304 may be implemented, for example, using one or more system-on-chips (SoCs), application-specific integrated circuits (ASICs), discrete analog and digital circuits, and other circuits. System circuitry 304 may be part of the implementation of any desired functionality in UE 300. In this regard, the system circuitry 304 may include logic to facilitate, for example, decoding and playing music and videos, such as MP3, MP4, MPEG, AVI, FLAC, AC3, or WAV decoding and playback; running applications; accepting user input; saving and retrieving application data; establishing, maintaining, and terminating cellular phone calls or data connections, such as Internet connections; establishing, maintaining, and terminating wireless network connections, Bluetooth connections, or other connections; and displaying relevant information on a user interface 310. The user interface 310 and input / output (I / O) interface 306 may include a graphical user interface, a touch-sensitive display, tactile feedback or other tactile output, voice or facial recognition input, buttons, switches, speakers, and other user interface elements. Other examples of the I / O interface 306 may include a microphone, video and still image cameras, temperature sensors, vibration sensors, rotation and orientation sensors, headphone and microphone input / output jacks, a universal serial bus (USB) connector, a memory card slot, a radiation sensor (e.g., an IR sensor), and other types of input.

[0037] refer to Figure 3The communication interface 302 may include radio frequency (RF) transmission (Tx) and reception (Rx) circuitry 316 that handles the transmission and reception of signals via one or more antennas 314. The communication interface 302 may include one or more transceivers. The transceiver may be a wireless transceiver that includes modulation / demodulation circuitry, a digital-to-analog converter (DAC), a shaping table, an analog-to-digital converter (ADC), filters, a waveform shaper, filters, preamplifiers, power amplifiers, and / or other logic for transmission and reception via one or more antennas or (for some devices) via a physical (e.g., wired) medium. The transmitted and received signals may conform to any of a variety of formats, protocols, modulations (e.g., QPSK, 16-QAM, 64-QAM, or 256-QAM), frequency channels, bit rates, and encodings. As a specific example, the communication interface 302 may include a transceiver that supports transmission and reception under 2G, 3G, BT, WiFi, Universal Mobile Telecommunications System (UMTS), High Speed ​​Packet Access (HSPA)+, 4G / Long Term Evolution (LTE), and 5G standards. However, the techniques described below are applicable to other wireless communication technologies, whether or not produced by the Third Generation Partnership Project (3GPP), the GSM Association, 3GPP2, IEEE, or other partners or standards bodies.

[0038] refer to Figure 3 , the system circuit 304 may include one or more processors 321 and memory 322. The memory 322 stores, for example, an operating system 324, instructions 326, and parameters 328. The processor 321 is configured to execute the instructions 326 to perform the desired functions of the UE 300. The parameters 328 may provide and specify configuration and operating options for the instructions 326. The memory 322 may also store any BT, WiFi, 3G, 4G, 5G, or other data that the UE 300 will send or has received through the communication interface 302. In various implementations, the system power of the UE 300 may be provided by a power storage device (such as a battery or a transformer).

[0039] The present disclosure describes several embodiments of methods and apparatus for configuring Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK) feedback for Physical Downlink Shared Channel (PDSCH) transmissions, which may be partially or fully implemented in the above Figure 2 and Figure 3 The method is implemented on a wireless network base station and / or user equipment described in the specification.

[0040] In one embodiment, reference Figure 4A method 400 for wireless communication includes configuring hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback for a physical downlink shared channel (PDSCH) transmission. The method 400 may include some or all of the following: step 410, receiving, by a user equipment (UE), radio resource control (RRC) parameters for configuring an enhanced dynamic HARQ-ACK feedback mode; step 420, receiving, by the UE, first downlink control information (DCI) including a first K, the first DCI corresponding to a first PDSCH; step 430, receiving, by the UE, a second DCI for a second PDSCH, the second DCI including a second K having an applicable value; and step 440, transmitting, by the UE, enhanced dynamic HARQ-ACK feedback according to a preset rule.

[0041] Referring to step 410, a base station (e.g., a RAN) transmits RRC parameters to the UE for configuring the UE in enhanced dynamic HARQ-ACK feedback mode. In one implementation, the RRC parameters may include: a pdsch-HARQ-ACK-Codebook with a positive value of enhancedDynamic-r16 to configure the UE in enhanced dynamic HARQ-ACK feedback mode. The value of enhancedDynamic-r16 may be 1.

[0042] Referring to step 420, the UE receives a first DCI corresponding to a first PDSCH. The first DCI includes a first K. K may be a PDSCH-to-HARQ_feedback timing indicator. In one implementation, the first K of the first DCI may have an applicable value. In another implementation, the first K may have a non-applicable value.

[0043] The K of the DCI may be referred to as K1. When K (or K1) is non-negative, K (or K1) has a numerical value or an applicable value. K (or K1) with an applicable value may indicate the scheduling timing between the PDSCH and the corresponding PUCCH, so that the UE may transmit HARQ-ACK information for the PDSCH in the slot in the PUCCH / PUSCH K after the corresponding PDSCH. For example, there may be K1 slots (or subslots) between the PUCCH and the PDSCH.

[0044] When K (or K1) is a negative value, such as but not limited to -1, K (or K1) has a non-numeric value (NNK1) or an inapplicable value. K (or K1) having an inapplicable value may indicate to the UE that the UE should store the HARQ-ACK feedback for the PDSCH.

[0045] Referring to step 430, the UE receives a second DCI corresponding to a second PDSCH. The second DCI includes a second K having an applicable value. For example, the second K of the second DCI may be 2 or 3.

[0046] Referring to step 440, according to a preset rule, the UE may transmit enhanced dynamic HARQ-ACK feedback to the base station.

[0047] In one embodiment, when the first DCI and the second DCI indicate the same priority and the same group, the UE combines the first HARQ-ACK feedback for the first PDSCH with the second HARQ-ACK feedback for the second PDSCH in the enhanced dynamic HARQ-ACK codebook. The UE transmits the enhanced dynamic HARQ-ACK codebook in the second K time slot after the second PDSCH. In one implementation, the first DCI and the second DCI may schedule the PDSCH with the same priority index. In another implementation, the first DCI and the second DCI may schedule the PDSCH with different priority indices.

[0048] DCI may have several formats, such as, but not limited to, DCI format 0_1, DCI format 0_2, DCI format 1_0, DCI format 1_1, and DCI format 1_2. The present disclosure may be applicable to at least one or all of these DCI formats.

[0049] For example, reference Figure 5A In time slot n, the UE receives a first PDSCH (PDSCH-1) 518 corresponding to DCI-1 510, where DCI-1 510 includes a first K1 (K1-1)=NNK1, a first priority index (PI-1)=1, and a first group index (GI-1)=1. In time slot n+1, the UE receives a second PDSCH (PDSCH-2) 528 corresponding to DCI (DCI-2) 520, where DCI-2 520 includes a second K1 (K1-2)=2, a second PI (PI-2)=1, and a second GI (GI-2)=1. Upon receiving DCI-2 including applicable K1, the same GI as DCI-1, and the same PI as DCI-1, the HARQ-ACK feedback of PDSCH-1 is combined with the HARQ-ACK feedback of PDSCH-2 and transmitted on time slot n+3 according to the K1-2 value in DCI-2, and the ACK / NACK is included in the enhanced dynamic HARQ-ACK codebook 570. In another implementation, both DCI-1 and DCI-2 may include PI=0 or GI=0.

[0050] In another implementation, the first DCI and / or the second DCI may not include a GI and / or PI value, and when the DCI does not include a GI and / or PI, the GI and / or PI may have a default value of 0. For example, referring to Figure 5B , the first DCI (DCI-1, 510b) may include K1-1, PI-1=0, and GI=0 of the not applicable number (NNK1); the second DCI (DCI-2, 520b) may include K1-2=2, but does not include PI or GI. Although DCI-2 does not include PI or GI, the default values ​​of PI and GI are both 0. Therefore, DCI-1 and DCI-2 indicate the same priority and the same group. The UE combines the HARQ-ACK feedback for PDSCH-1 with the HARQ-ACK feedback for PDSCH-2 in the enhanced dynamic HARQ-ACK codebook 570, and transmits the enhanced dynamic HARQ-ACK codebook 570 on time slot n+3 according to the K1-2 value in DCI-2.

[0051] In another implementation, the first K of the first DCI may also include an applicable value. Figure 5C , the first DCI (DCI-1, 510c) may include an applicable value (e.g., K1-1=2) of K. Upon receiving a second DCI having an applicable value (e.g., K1-2=2) and indicating the same priority and the same group as the first DCI, the UE combines the HARQ-ACK feedback of PDSCH-1 with the HARQ-ACK feedback of PDSCH-2 in the enhanced dynamic HARQ-ACK codebook 570 and transmits the enhanced dynamic HARQ-ACK codebook 570 on time slot n+3 according to the K1-2 value in DCI-2.

[0052] In another embodiment, the UE transmits an enhanced dynamic HARQ-ACK codebook for ultra-reliable low-latency communication (URLLC) in an unlicensed band configured by a specific DCI format, and when a specific PDSCH is scheduled by a DCI with a specific DCI format, the UE determines to which PDSCH group the specific PDSCH belongs. For example, the DCI has DCI formats 1-2. The DCI with the specific DCI format can indicate the PDSCH group index according to a predefined rule.

[0053] For the first predefined rule, the PDSCH group index may be predefined or implicitly acquired, and the DCI may not include a specific bit field of the PDSCH group index. The first predefined rule may include at least one of the following.

[0054] DCI with a specific DCI format determines the PDSCH group index based on the DCI priority indicator. For example, the PDSCH group index can be determined based on the priority indicator. When the priority index value is 0, the PDSCH group index is also 0; and when the priority index value is 1, the PDSCH group index is also 1.

[0055] The DCI with a specific DCI format determines the PDSCH group index as a default value. For example, all PDSCHs scheduled by the specific DCI format (e.g., DCI format 1_2) belong to the same PDSCH group, and the PDSCH group index can be predefined as 0 (or 1).

[0056] DCI with a specific DCI format determines the PDSCH group index according to a predefined value configured by an RRC message. For example, an RRC message can be sent from the RAN to the UE to configure that the PDSCH scheduled by DCI format 1_2 belongs to group 1 (or group 0).

[0057] For the second predefined rule, a bit field of a PDSCH group index may be added to a DCI having a specific DCI format. The bit field of the PDSCH group index in the DCI rule may be determined in the following manner.

[0058] Two DCIs with different priority indexes include different PDSCH group indexes. When two DCIs have the same priority index, the two DCIs may belong to different groups. For example, PDSCHs of different priorities may not belong to the same PDSCH group. When the priority indicators are different, the PDSCH group indexes in the two DCIs may be different, so that the scheduled PDSCCH groups are triggered only for HARQ-ACK feedback and the number of requested PDSCH group bit fields is not required in the DCI. For another example, when the priority indicators are the same, the PDSCH group indexes in the two DCIs may be different, so that the number of requested PDSCH groups in the DCI may be 2, and the total downlink allocation index (T-DAI) may be accumulated only in the same priority indicator. In one implementation, priority index 1 can be divided into two PDSCH groups and priority index 0 can have two PDCCH groups. Therefore, two groups with priority index 0 and two groups with priority index 1, a total of 4 PDSCH groups are generated.

[0059] In another embodiment, the UE receives a second DCI including a new feedback indication (NFI) whose value is not flipped after the first DCI is received; and when the first DCI and the second DCI indicate the same priority and the same group, the UE combines the first HARQ-ACK feedback for the first PDSCH with the second HARQ-ACK feedback for the second PDSCH in the enhanced dynamic HARQ-ACK codebook. The UE may transmit the enhanced dynamic HARQ-ACK codebook in the second K subslot after the second PDSCH.

[0060] In another implementation, the second DCI includes the number of requested PDSCH groups with a positive value, for example, the number of requested PDSCH groups in the second DCI is 1. When the first DCI and the second PDI indicate the same priority, the UE combines the first HARQ-ACK feedback for the first PDSCH with the second HARQ-ACK feedback for the second PDSCH in the enhanced dynamic HARQ-ACK codebook.

[0061] For example, reference Figure 6A In time slot n, the UE receives a first DCI (DCI-1, 610) scheduling a first PDSCH (PDSCH1, 618). The first DCI may include a priority indicator (PI) = 1, a PDSCH group index (GI) = 0, a new feedback indication (NFI) = 0, a downlink allocation index (DAI) = 1, and a K value (K1) = 1. After the UE receives the first DCI, the UE performs a listen-before-talk (LBT) procedure.

[0062] When LBT is successful, the UE transmits ACK / NCK information including one-bit ACK / NACK on sub-slot 660 .

[0063] When LBT fails, the UE is unable to send ACK / NACK information in subslot 660. The UE receives a second PDSCH (PDSCH2, 628) scheduled by a second DCI (DCI-2, 620). The second DCI includes PI=1, GI=1, NFI=0, DAI=2, and K1=1. When the base station (e.g., gNB) is unable to successfully receive HARQ-ACK feedback for PDSCH1, the base station may indicate the requested number of PDSCH groups = 1 to inform the UE to feed back HARQ-ACK information for both PDSCH group 0 and PDSCH group 1. After the UE receives the second DCI, it combines the ACK / NACK information for the first PDSCH and the ACK-NACK information for the second PDSCH in the ACK / NCK codebook. The ACK / NACK codebook may include 2-bit ACK / NCK information. The UE transmits 2-bit ACK / NACK information in subslot 3 670.

[0064] In another implementation, when the HARQ-ACK codebook with PI = 0 is discarded due to a collision with the HARQ-ACK codebook with PI = 1 in time slot n, the base station may send another DCI next time and indicate the same PI = 0, and the NFI is not flipped. After the UE receives the DCI, the UE may report the discarded HARQ-ACK codebook. For example, but not limitation, the second DCI may fall back to include DCI format 1_0.

[0065] For example, reference Figure 6B , the first PDSCH (PDSCH1, 618) is scheduled by the first DCI (DCI-1, 610b). For example, the first DCI may have DCI format 1_1 or DCI format 2_2. The first DCI may include PI=0, GI=0, and K1=3. The second PDSCH (PDSCH2, 628) is scheduled by the second DCI (DCI-2, 620b). For example, the second DCI may have DCI format 1_1 or DCI format 1_2. The second DCI may include PI=1, GI=1, and K1=1. Upon receiving PDSCH2 scheduled by DCI-2, the UE may feedback the HARQ-ACK codebook (670b) for PI=1 and GI=1, and discard the HARQ-ACK codebook for PI=0 including ACK / NACK information for PDSCH1. The UE may receive another PDSCH, namely, a third PDSCH (PDSCH3, 638) scheduled by a third DCI (DCI-3, 630). The third DCI may have DCI format 1_0 or DCI format 2_1. The third PDI may include PI=0, GI=0, and K1=2, and the UE may feedback a HARQ-ACK codebook with two ACK / NACK bits (680) for PI=0 and GI=1, including the discarded HARQ-ACK information for PDSCH1.

[0066] In another embodiment, a specific bit field may be added to a specific DCI format. In one implementation, the specific bit field is a bit field of a new feedback indication (NFI), and the specific DCI format is DCI format 1_2.

[0067] In one implementation, when the second DCI includes a bit field for NFI and NFI is flipped, the counter downlink allocation index (C-DAI) and the total downlink allocation index (T-DAI) are reset, the UE discards the first HARQ-ACK feedback for the first PDSCH, and the UE combines the second HARQ-ACK feedback for the second PDSCH in the enhanced dynamic HARQ_ACK codebook. C-DAI and T-DAI may not be reset by the PUCCH transmission opportunity. The UE transmits the enhanced dynamic HARQ-ACK codebook in the second K slot after the second PDSCH.

[0068] In another implementation, when the NFI of the second DCI is not flipped, the C-DAI and T-DAI are accumulated within the PDSCH group until the NFI of the PDSCH group is flipped. The UE combines the first HARQ-ACK feedback for the first PDSCH with the second HARQ-ACK feedback for the second PDSCH in an enhanced dynamic HARQ-ACK codebook. The UE transmits the enhanced dynamic HARQ-ACK codebook in the second K time slot after the second PDSCH.

[0069] In another embodiment, based on which predefined rule is satisfied, the UE determines to combine the first HARQ-ACK feedback for the first PDSCH with the second HARQ-ACK feedback for the second PDSCH in the enhanced dynamic HARQ-ACK codebook. In this embodiment, the new bit field of NFI is not added to a specific DCI format (e.g., DCI format 1_2). The predefined rule may include at least one of the following.

[0070] For one rule, the first PDSCH is in a predefined time window relative to the second PDSCH. In one implementation, after the UE receives the second DCI (e.g., DCI format 1_2), the UE reports the HARQ-ACK information of the scheduled PDSCH in the predefined time window. The duration of the window can be at the subslot level, and each subslot contains 4 or 7 OFDM symbols. In another implementation, the predefined time window includes at least one subslot; and when the first PDSCH is in the predefined time window relative to the second PDSCH, the UE combines the first HARQ-ACK feedback for the first PDSCH with the second HARQ-ACK feedback for the second PDCCH in the enhanced dynamic HARQ-ACK codebook.

[0071] For another rule, the UE determines whether the number of ACK / NACK bits in the enhanced dynamic HARQ-ACK codebook exceeds a predefined threshold. In one implementation, when the number of ACK / NACK bits in the HARQ-ACK codebook exceeds a predefined value, the C-DAI and T-DAI of the PDSCH group may be reset. Otherwise, the ACK / NACK bits in the HARQ-ACK codebook may be accumulated within the PDSCH group. In another implementation, when the UE determines that the number of ACK / NACK bits in the enhanced dynamic HARQ-ACK codebook exceeds a predefined threshold: the counter downlink allocation index (C-DAI) and the total downlink allocation index (T-DAI) are reset, the UE discards the first HARQ-ACK feedback for the first PDSCH, and the UE combines the second HARQ-ACK feedback for the second PDSCH in the enhanced dynamic HARQ-ACK codebook. When the UE determines that the number of ACK / NACK bits in the enhanced dynamic HARQ-ACK codebook does not exceed the predefined threshold: C-DAI and T-DAI are accumulated, and the UE combines the first HARQ-ACK feedback for the first PDSCH with the second HARQ-ACK feedback for the second PDSCH in the enhanced dynamic HARQ-AACK codebook.

[0072] For another rule, the UE determines whether the NFI in the last DCI is flipped. In one implementation, the NFI may be the same as the last DCI detected by the UE in the PDCCH monitoring opportunity and indicate the same PUCCH transmission opportunity. In another implementation, when the UE determines that the NFI in the last DCI is flipped: the counter downlink allocation index (C-DAI) and the total downlink allocation index (T-DAI) are reset, the UE discards the first HARQ-ACK feedback for the first PDSCH, and the UE combines the second HARQ-ACK feedback for the second PDSCH in the enhanced dynamic HARQ-ACK codebook. When the UE determines that the NFI in the last DCI is not flipped and the first DCI and the second DCI indicate the same priority and the same group: the C-DAI and the T-DAI are accumulated, and the UE combines the first HARQ-ACK feedback for the first PDSCH with the second HARQ-ACK feedback for the second PDSCH in the enhanced dynamic HARQ-ACK codebook.

[0073] For example, reference Figure 7, three DCI schedules including DCI-1 710, DCI-2 720, and DCI-3 730 include three PDSCHs: PDSCH-1 718, PDSCH-2 728, and PDSCH-3 738. The UE combines HARQ-ACK feedback for these three PDCCHs in an enhanced dynamic HARQ-ACK codebook 770 with PI=1 and GI=1, and transmits the enhanced dynamic HARQ-ACK codebook in the same PUCCH transmission opportunity. The first DCI and the third DCI of the PUCCH transmission opportunity may not include an NFI, such as DCI format 1_2, and thus DCI-1 and DCI-3 do not have an NFI, but have the same PI as the second DCI. The second DCI may have DCI format 1_1. According to at least one of the rules discussed above, the NFI in the first DCI and the last DCI may be the same as the second DCI, that is, NFI=1, and not flipped. The UE may feed back 3-bit HARQ-ACK information in the codebook for PI = 1 and GI = 1. In another implementation, DCI-1 and DCI-3 may not have NFI and group index information.

[0074] In another embodiment, the DCI may include a bit field for uplink (UL) DAI. When the DCI is not configured with UL-TotalDAI-Included-r16 and HARQ-ACK transmission requires two HARQ-ACK codebooks of different priorities, the UL DAI in the DCI corresponds to the HARQ-ACK codebook with the higher priority. This embodiment describes a method for a UE to interpret the UL DAI bit field in a UL DCI format (e.g., but not limited to, DCI format 0_1 ​​or DCI format 0_2).

[0075] In one implementation, when the time slot indicated in the DCI-scheduled PUCCH transmission opportunity for HARQ-ACK feedback is a time slot for scheduled PUSCH transmission, the UE may multiplex the HARQ-ACK transmission on the PUSCH. When the HARQ-ACK information is multiplexed in the PUSCH transmission, the HARQ-ACK information may be determined in at least one of the following situations.

[0076] For example, when PUSCH transmission is scheduled by a DCI format that does not have UL-TotalDAI-Included-r16 configured except for PDSCH group g, the DCI format has the value The DCI field of can be used for the enhanced dynamic HARQ-ACK codebook of PDSCH group g or the priority index that needs to be reported here.

[0077] For example, when UL-TotalDAI-Included-r16 is not configured and two HARQ-ACK codebooks with different priority indicators need to be transmitted on the PUSCH, the PUSCH is scheduled by DCI with DCI format 0_1 ​​or DCI format 0_2. The DAI in the DCI can be used to indicate the HARQ-ACK codebook with a higher priority.

[0078] For another example, when UL-TotalDAI-Included-r16 is configured, these UL DAI fields may be applied separately to each PDSCH group or each priority index.

[0079] The present disclosure describes methods, apparatus, and computer-readable media for wireless communications. The present disclosure addresses the problem of configuring hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback for physical downlink shared channel (PDSCH) transmissions. The methods, apparatus, and computer-readable media described in the present disclosure can facilitate the performance of wireless communications by configuring HARQ-ACK feedback for PDSCH transmissions, thereby improving efficiency and overall performance. The methods, apparatus, and computer-readable media described in the present disclosure can improve the overall efficiency of wireless communication systems.

[0080] Reference throughout this specification to features, advantages, or similar language does not imply that all features and advantages that can be achieved with the present solution should or are included in any single implementation thereof. Rather, language referring to features and advantages is understood to indicate that a particular feature, advantage, or characteristic described in connection with an embodiment is included in at least one embodiment of the present solution. Thus, discussion of features and advantages, and similar language, throughout this specification may, but do not necessarily, refer to the same embodiment.

[0081] Furthermore, in one or more embodiments, the described features, advantages, and characteristics of the present solution may be combined in any suitable manner. Based on the description herein, one of ordinary skill in the relevant art will recognize that the present solution may be practiced without one or more of the specific features or advantages of a particular embodiment. In other cases, additional features and advantages may be recognized in certain embodiments, which may not be present in all embodiments of the present solution.

Claims

1. A method for wireless communication, comprising: Configure Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK) feedback for Physical Downlink Shared Channel (PDSCH) transmissions in the following manner: Receiving, by a user equipment UE, a radio resource control (RRC) parameter for configuring an enhanced dynamic HARQ-ACK feedback mode; Receiving, by the UE, first downlink control information DCI including a first K, where the first DCI corresponds to a first PDSCH; receiving, by the UE, a second DCI for a second PDSCH, the second DCI including a second K having applicable values ​​and a bit field for an uplink (UL) downlink allocation index (DAI), wherein in response to HARQ-ACK transmission requiring two HARQ-ACK codebooks for different priorities and the second DCI not being configured with UL-TotalDAI-Included-r16, the UL DAI in the second DCI corresponds to a HARQ-ACK codebook of a higher priority; and The UE transmits enhanced dynamic HARQ-ACK feedback according to a preset rule.

2. The method according to claim 1, wherein: The first K includes a non-applicable value of -1; and The RRC parameter indicating the enhanced dynamic HARQ-ACK feedback mode includes: pdsch-HARQ-ACK-Codebook with enhancedDynamic-r16 having a positive value.

3. The method according to claim 1, wherein: In response to the first DCI and the second DCI indicating the same priority and the same group, the UE combines, in an enhanced dynamic HARQ-ACK codebook, first HARQ-ACK feedback for the first PDSCH and second HARQ-ACK feedback for the second PDSCH.

4. The method according to claim 3, wherein: The UE transmits the enhanced dynamic HARQ-ACK codebook in a time slot at the second K after the second PDSCH.

5. The method according to claim 1, wherein: The second DCI includes a new feedback indication NFI whose value is not flipped after the first DCI is received; and In response to the first DCI and the second DCI indicating the same priority and the same group, the UE combines, in an enhanced dynamic HARQ-ACK codebook, first HARQ-ACK feedback for the first PDSCH and second HARQ-ACK feedback for the second PDSCH.

6. The method according to claim 5, wherein: The UE transmits the enhanced dynamic HARQ-ACK codebook in the subslot at the second K after the second PDSCH.

7. The method according to claim 5, wherein: The second DCI includes a number of requested PDSCH groups having a positive value; and In response to the first DCI and the second DCI indicating the same priority, the UE combines, in an enhanced dynamic HARQ-ACK codebook, first HARQ-ACK feedback for the first PDSCH and second HARQ-ACK feedback for the second PDSCH.

8. The method of claim 1, wherein: The UE transmits an enhanced dynamic HARQ-ACK codebook for ultra-reliable low-latency communication (URLLC) in an unlicensed band configured by a specific DCI format; and The DCI having the specific DCI format indicates a PDSCH group index according to a predefined rule.

9. The method according to claim 8, wherein: The predefined rules include at least one of the following: The DCI having the specific DCI format determines the PDSCH group index according to a priority indicator of the DCI; The DCI having the specific DCI format determines the PDSCH group index as a default value; or The DCI having the specific DCI format determines the PDSCH group index according to a predefined value configured by an RRC message.

10. The method of claim 1, wherein: The UE transmits an enhanced dynamic HARQ-ACK codebook for ultra-reliable low-latency communication (URLLC) in an unlicensed band configured by a specific DCI format; and The DCI having the specific DCI format includes a bit field for a PDSCH group index conforming to a predefined rule.

11. The method according to claim 10, wherein: The predefined rule includes: two DCIs with different priority indexes include different PDSCH group indexes.

12. The method of claim 1, wherein: The second DCI in a specific format includes a bit field of NFI; In response to the NFI of the second DCI being flipped: The counters downlink allocation index C-DAI and total downlink allocation index T-DAI are reset, The UE discards the first HARQ-ACK feedback for the first PDSCH, and Combining, by the UE, second HARQ-ACK feedback for the second PDSCH in an enhanced dynamic HARQ-ACK codebook; and In response to the second DCI, the NFI is not flipped: The C-DAI and the T-DAI are accumulated, and The UE combines, in the enhanced dynamic HARQ-ACK codebook, first HARQ-ACK feedback for the first PDSCH and second HARQ-ACK feedback for the second PDSCH.

13. The method according to claim 12, wherein: The UE transmits the enhanced dynamic HARQ-ACK codebook in a time slot at the second K after the second PDSCH.

14. The method of claim 1, wherein: In response to satisfying a predefined rule, the UE determines to combine first HARQ-ACK feedback for the first PDSCH with second HARQ-ACK feedback for the second PDSCH in an enhanced dynamic HARQ-ACK codebook.

15. The method according to claim 14, wherein: The predefined rules include at least one of the following: The first PDSCH is in a predefined time window relative to the second PDSCH; determining, by the UE, whether the number of ACK / NACK bits in the enhanced dynamic HARQ-ACK codebook exceeds a predefined threshold; or The UE determines whether the NFI in the latest DCI is flipped.

16. The method of claim 15, wherein: The predefined time window includes at least one sub-time slot; and In response to the first PDSCH being in the predefined time window relative to the second PDSCH, the UE combines, in the enhanced dynamic HARQ-ACK codebook, first HARQ-ACK feedback for the first PDSCH with the second HARQ-ACK feedback for the second PDSCH.

17. The method of claim 15, wherein: In response to the UE determining that the number of ACK / NACK bits in the enhanced dynamic HARQ-ACK codebook exceeds the predefined threshold: The counters downlink allocation index C-DAI and total downlink assignment index T-DAI are reset, The UE discards the first HARQ-ACK feedback for the first PDSCH, and Combining, by the UE, second HARQ-ACK feedback for the second PDSCH in the enhanced dynamic HARQ-ACK codebook; and In response to the UE determining that the number of ACK / NACK bits in the enhanced dynamic HARQ-ACK codebook does not exceed the predefined threshold: The C-DAI and the T-DAI are accumulated, and The UE combines, in the enhanced dynamic HARQ-ACK codebook, first HARQ-ACK feedback for the first PDSCH and the second HARQ-ACK feedback for the second PDSCH.

18. The method of claim 15, wherein: In response to the UE determining that the NFI in the last DCI is flipped: The counters downlink allocation index C-DAI and total downlink allocation index T-DAI are reset, The UE discards the first HARQ-ACK feedback for the first PDSCH, and Combining, by the UE, second HARQ-ACK feedback for the second PDSCH in the enhanced dynamic HARQ-ACK codebook; and In response to the UE determining that the NFI in the last DCI is not flipped, and the first DCI and the second DCI indicate the same priority and the same group: The C-DAI and the T-DAI are accumulated, and The UE combines, in the enhanced dynamic HARQ-ACK codebook, first HARQ-ACK feedback for the first PDSCH and the second HARQ-ACK feedback for the second PDSCH.

19. The method according to any one of claims 16 to 18, wherein: The UE transmits the enhanced dynamic HARQ-ACK codebook in a time slot at the second K after the second PDSCH.

20. A method for wireless communication, comprising: Configure Hybrid Automatic Repeat Request Acknowledgement (HARQ-ACK) feedback for Physical Downlink Shared Channel (PDSCH) transmissions in the following manner: The radio access network RAN ​​sends a radio resource control RRC parameter for configuring an enhanced dynamic HARQ-ACK feedback mode to the user equipment UE; Sending, by the RAN, first downlink control information DCI including a first K to the UE, where the first DCI corresponds to a first PDSCH; sending, by the RAN, a second DCI for a second PDSCH to the UE, the second DCI including a second K having an applicable value and a bit field for an uplink (UL) downlink allocation index (DAI), wherein in response to HARQ-ACK transmission requiring two HARQ-ACK codebooks for different priorities and the second DCI not being configured with UL-TotalDAI-Included-r16, the UL DAI in the second DCI corresponds to a HARQ-ACK codebook of a higher priority; and The RAN receives enhanced dynamic HARQ-ACK feedback from the UE according to a preset rule.

21. A wireless communication device comprising a processor and a memory, wherein the processor is configured to read code from the memory and implement the method according to any one of claims 1 to 20.

22. A computer program product comprising computer readable program medium code stored thereon, which, when executed by a processor, causes the processor to implement the method according to any one of claims 1 to 20.

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