Apparatus and method for hybrid automatic repeat request feedback transmission

Abstract

An apparatus and method for hybrid automatic repeat request (HARQ) feedback transmission are provided. A method for HARQ feedback transmission includes receiving a multicast broadcast service (MBS) transport block (TB) from a base station, decoding the MBS TB, and transmitting HARQ feedback in the form of a negative acknowledgement only (NACK) report to the base station when the UE wrongly decodes the MBS TB. This may address problems in the prior art, reduce the number of required feedback resources, save UE processing and uplink (UL) transmissions, provide more reliable MBS data reception with lower latency, provide better user experience, provide good communication performance, and / or provide high reliability.

Description

[0001] The present disclosure is a divisional application of the PCT international patent application PCT / CN2020 / 107485 with an application date of August 6, 2020, which has entered the Chinese national phase with Chinese patent application number 202080104504.1 and the invention name being “Device and method for hybrid automatic repeat request feedback transmission”. Technical Field

[0002] The present disclosure relates to the field of communication systems, and more specifically, to an apparatus and method for hybrid automatic repeat request (HARQ) feedback transmission, which can provide good communication performance and / or high reliability. Background Art

[0003] In the past development of the fifth generation-new radio (5G-NR) radio access technology (RAT) systems and networks in Release 15 and Release 16 of the 3rd generation partnership project (3GPP), 5G multicast and broadcast type services were not part of the main focus, although there are some important use cases where multicast / broadcast can significantly broaden the scope of applications and improve user experience. In Release 17, 3GPP is currently looking to introduce new radio transceiver capabilities / technologies and integrate them into the 5G-NR radio access network (RAN) to provide multicast / broadcast services to support applications such as public safety, mission-critical, vehicle-to-everything (V2X), internet protocol TV (IPTV), group communications and / or the internet of things (IoT).

[0004] According to the approved 3GPP work item description, one of the main operational requirements for 5G-NR RAN to support multicast / broadcast services is the ability to deliver service content to UEs in any of the currently defined radio resource control (RRC) states (i.e., idle, inactive, and connected). To achieve / meet this requirement, the current existing NR radio system design has inefficiencies in reliably providing multicast / broadcast content, especially for UEs in RRC idle and inactive states. These inefficiencies include poor downlink (DL) data reception performance (due to the lack of channel state information and HARQ feedback available to the gNB), and long packet delays (due to unnecessary / excessive blind retransmissions of packets if the existing physical broadcast channel content delivery mechanism is followed).

[0005] Furthermore, since the number of UEs in a network cell that require multicast / broadcast services may be quite large for applications such as V2X, IoT, sports events (in and around stadiums), and / or sometimes even public safety / mission-critical users, it is not possible to simultaneously connect and serve this large number of UEs through a single gNB. How to solve the above problems remains a challenge.

[0006] Therefore, a device and method for HARQ feedback transmission are needed to solve the problems in the prior art, reduce the number of feedback resources required, save UE processing and uplink (UL) transmission, provide more reliable MBS data reception with lower latency, provide better user experience, provide good communication performance, and / or provide high reliability. Summary of the invention

[0007] The purpose of the present disclosure is to propose a device and method for HARQ feedback transmission, which can solve the problems in the prior art, reduce the number of feedback resources required, save UE processing and UL transmission, provide more reliable MBS data reception with lower latency, provide better user experience, provide good communication performance, and / or provide high reliability.

[0008] In a first aspect of the present disclosure, a user equipment (UE) includes a memory, a transceiver, and a processor coupled to the memory and the transceiver. The transceiver is configured to receive a multicast broadcast service (MBS) transport block (TB) from a base station, and the processor is configured to decode the MBS TB; when the processor erroneously decodes the MBS TB, the transceiver transmits a hybrid automatic repeat request (HARQ) feedback in the form of a negative acknowledgement-only (NACK-only) report to the base station.

[0009] In a second aspect of the present disclosure, a method for HARQ feedback transmission for a UE includes receiving an MBS TB from a base station, decoding an MBS TB, and transmitting HARQ feedback in the form of a NACK-only report to the base station when the UE erroneously decodes the MBS TB.

[0010] In a third aspect of the present disclosure, a base station includes a memory, a transceiver, and a processor coupled to the memory and the transceiver. The transceiver is configured to transmit an MBS TB to a UE; when the UE erroneously decodes the MBS TB, the transceiver receives HARQ feedback in the form of NACK-only reporting from the UE.

[0011] In a fourth aspect of the present disclosure, a method for HARQ feedback transmission of a base station includes transmitting an MBS TB to a UE, and receiving HARQ feedback in the form of NACK-only reporting from the UE when the UE erroneously decodes an MBS TB.

[0012] In a fifth aspect of the present disclosure, a non-transitory machine-readable storage medium stores instructions, wherein when the instructions are executed by a computer, the computer is caused to execute the above method.

[0013] In a sixth aspect of the present disclosure, a chip includes a processor for calling and running a computer program stored in a memory so that a device equipped with the chip executes the above method.

[0014] In a seventh aspect of the present disclosure, a computer-readable storage medium stores a computer program, wherein the computer program enables a computer to execute the above method.

[0015] In an eighth aspect of the present disclosure, a computer program product includes a computer program, wherein the computer program enables a computer to execute the above method.

[0016] In a ninth aspect of the present disclosure, a computer program is provided, which enables a computer to execute the above method. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present disclosure or the prior art, the following drawings described in the embodiments will be briefly introduced. Obviously, the drawings are only some embodiments of the present disclosure, and ordinary technicians in this field can obtain other drawings from these drawings without prerequisites.

[0018] Figure 1 It is a block diagram of a base station and one or more UEs communicating in a communication network system according to an embodiment of the present disclosure.

[0019] Figure 2 is a flowchart illustrating a method for HARQ feedback transmission of a UE according to an embodiment of the present disclosure.

[0020] Figure 3 is a flowchart illustrating a method for HARQ feedback transmission of a base station according to an embodiment of the present disclosure.

[0021] Figure 4 is a block diagram of a wireless communication system according to an embodiment of the present disclosure. DETAILED DESCRIPTION

[0022] The embodiments of the present disclosure describe in detail the technical problems, structural features, implementation purposes and effects thereof with reference to the following drawings. Specifically, the terms in the embodiments of the present disclosure are only used for the purpose of describing specific embodiments and cannot limit the present disclosure.

[0023] In some embodiments of the present disclosure, one possible way to provide multicast / broadcast services for applications such as V2X, IoT, sports events (in and around stadiums), and / or sometimes even public safety / mission-critical users is to allow RRC idle and inactive UEs to receive data packets without any active connection. Therefore, the above-mentioned inefficiency issues and challenges of the two wireless communications for delivering data content to UEs in idle / inactive states in the prior art should be addressed.

[0024] In some embodiments of the present disclosure, for the HARQ feedback reporting mechanism of the present invention, it is intended to improve the DL data reception performance of UEs operating in RRC idle and inactive states by feeding back NACK reporting to the gNB only when the DL data packet is not successfully decoded. This also helps to reduce multicast / broadcast content delivery delays by retransmitting the same data packet to the UE only when necessary. By utilizing sequence-based signals, this allows UEs to share common physical random-access channel (PRACH) resources and random-access (RA) preambles or common PRACH and RA preamble sets configured by the network to represent NACK information. Therefore, this greatly improves the utilization efficiency of UL resources. Other benefits of adopting the newly invented downlink HARQ reporting mechanism for UEs in RRC idle and inactive states:

[0025] The user experience is greatly enhanced through better reception performance and shortened data latency.

[0026] Reduce UE processing and power consumption in uplink feedback preparation.

[0027] Simplified HARQ feedback detection process at gNB receiver.

[0028] Figure 1 A block diagram of a base station 20 and one or more UEs 10 for communication in a communication network system 30 provided according to an embodiment of the present disclosure in some embodiments is shown. The communication network system 30 includes a UE 10 and a base station 20 (e.g., a gNB). The UE 10 may include a memory 12, a transceiver 13, and a processor 11 coupled to the memory 12 and the transceiver 13. The base station 20 may include a memory 22, a transceiver 23, and a processor 21 coupled to the memory 22 and the transceiver 23. The processor 11 or 21 may be configured to implement the suggested functions, processes, and / or methods described in this specification. The layers of the wireless interface protocol may be implemented in the processor 11 or 21. The memory 12 or 22 is operably coupled to the processor 11 or 21 and stores various information to operate the processor 11 or 21. The transceiver 13 or 23 is operably coupled to the processor 11 or 21, and the transceiver 13 or 23 transmits and / or receives wireless signals.

[0029] The processor 11 or 21 may include an application-specific integrated circuit (ASIC), other chipsets, logic circuits and / or data processing devices. The memory 12 or 22 may include a read-only memory (ROM), a random access memory (RAM), flash memory, a memory card, a storage medium and / or other storage devices. The transceiver 13 or 23 may include a baseband circuit to process radio frequency signals. When the embodiments are implemented in software, the techniques described herein may be implemented with modules (e.g., processes, functions, etc.) that perform the functions described herein. These modules may be stored in the memory 12 or 22 and executed by the processor 11 or 21. The memory 12 or 22 may be implemented within the processor 11 or 21, or implemented outside the processor 11 or 21, in which case the memory 12 or 22 may be communicatively coupled to the processor 11 or 21 via various means known in the art.

[0030] Communications between UEs involve V2X communications based on sidelink technologies developed under Release 17 and higher versions of 3GPP long term evolution (LTE) and new radio (NR), including vehicle-to-vehicle (V2V), vehicle-to-pedestrian (V2P), and vehicle-to-infrastructure / network (V2I / N). UEs communicate directly through sidelink interfaces such as PC5 interfaces. Some embodiments of the present disclosure relate to sidelink communication technologies in Release 17 and higher versions of 3GPP NR. Some embodiments of the present disclosure relate to mobile cellular communication technologies in Release 17 and higher versions of 3GPP NR for providing multicast and broadcast services.

[0031] In some embodiments, the transceiver 13 is configured to receive an MBS TB from the base station 20; the processor 11 is configured to decode the MBS TB; when the processor 11 erroneously decodes the MBS TB, the transceiver 13 transmits HARQ feedback in the form of a NACK-only report to the base station 20. This can solve the problems in the prior art, reduce the number of feedback resources required, save UE processing and UL transmission, provide more reliable MBS data reception with lower latency, provide a better user experience, provide good communication performance, and / or provide high reliability.

[0032] In some embodiments, the transceiver 23 is configured to transmit an MBS TB to the UE 10; when the UE 10 erroneously decodes the MBS TB, the transceiver 23 receives HARQ feedback in the form of a NACK-only report from the UE 10. This can solve the problems in the prior art, reduce the number of feedback resources required, save UE processing and UL transmission, provide more reliable MBS data reception with lower latency, provide a better user experience, provide good communication performance, and / or provide high reliability.

[0033] In some embodiments, UE 10 is in a radio resource control (RRC) idle state and / or an RRC inactive state. In some embodiments, when processor 11 successfully decodes an MBS TB, transceiver 13 does not feed back any positive acknowledgment ACK report to base station 20. In some embodiments, processor 11 is configured with a common uplink resource or a common uplink resource set shared between UE 10 and one or more UEs in the same cell as UE 10. In some embodiments, the common uplink resource or the common uplink resource set is configured to the processor using cell-specific network RRC signaling. In some embodiments, the common uplink resource or the common uplink resource set includes a physical random access channel (PRACH) resource and / or a random access (RA) preamble. In some embodiments, the RA preamble includes a sequence-based RA preamble.

[0034] In some embodiments, a sequence-based RA preamble is used to represent NACK-only information, and the NACK-only information is used for HARQ feedback in the form of NACK-only reporting in a PRACH resource of a random access channel RACH opportunity. In some embodiments, the HARQ feedback in the form of NACK-only reporting in a PRACH resource of a RACH opportunity corresponds to the best synchronization signal block (SSB) of the UE 10. In some embodiments, the processor 11 determines the SSB index and / or frame timing of the best SSB in part through a physical broadcast channel (PBCH) demodulation reference signal (DMRS) and / or PBCH data. In some embodiments, the transceiver 13 is configured to transmit a PRACH / RA preamble on a configured PRACH resource associated with the best SSB index and / or frame timing.

[0035] In some embodiments, the association between the subset of SSBs or PRACH resources and / or preamble indexes in the SS burst set is configured by a parameter set in the system information. In some embodiments, the transceiver 13 is configured to transmit the RA preamble to notify the base station 20 of the best SSB by using the RACH opportunity corresponding to the best SSB and the common NACK-only PRACH resource. In some embodiments, the transceiver 13 is configured to receive a retransmission of the MBS TB from the base station 20. In some embodiments, the retransmission of the MBS TB is transmitted via a unicast physical downlink shared channel (PDSCH).

[0036] In some embodiments, the UE 10 is located in a specific group associated with the detected RACH opportunity / SSB beam. In some embodiments, a RACH opportunity is a common PRACH resource / sequence for HARQ feedback in the form of NACK-only reporting, and is shared or used by the UE 10 or one or more UEs in the same cell as the UE 10. In some embodiments, the processor 11 is configured to calculate the transmit power for transmitting the RA preamble based on the downlink path loss and the target received power of the RA preamble. In some embodiments, the target received power is configured by the base station 20. In some embodiments, a range of transmit power levels corresponding to different downlink reference signal received power (RSRP) thresholds is configured by the base station 20, and the processor 11 selects a suitable power level from the range of transmit power levels to transmit HARQ feedback in the form of NACK-only reporting based on the measured downlink RSRP level.

[0037] Figure 2 A method 200 for HARQ feedback transmission for a UE according to an embodiment of the present disclosure is shown. In some embodiments, the method 200 includes: block 202, receiving an MBS TB from a base station; block 204, decoding the MBS TB; block 206, when the UE erroneously decodes the MBS TB, transmitting HARQ feedback in the form of a NACK-only report to the base station. This can solve the problems in the prior art, reduce the number of feedback resources required, save UE processing and UL transmission, provide more reliable MBS data reception with lower latency, provide a better user experience, provide good communication performance, and / or provide high reliability.

[0038] Figure 3A method 300 for HARQ feedback transmission for a base station according to an embodiment of the present disclosure is shown. In some embodiments, the method 300 includes: block 302, transmitting an MBS TB to a UE; block 304, receiving HARQ feedback in the form of a NACK-only report from the UE when the UE erroneously decodes the MBS TB. This can solve the problems in the prior art, reduce the number of feedback resources required, save UE processing and UL transmission, provide more reliable MBS data reception with lower latency, provide a better user experience, provide good communication performance, and / or provide high reliability.

[0039] In some embodiments, the UE is in an RRC idle state and / or an RRC inactive state. In some embodiments, when the UE successfully decodes the MBS TB, the UE does not feed back any positive acknowledgment ACK report to the base station. In some embodiments, the method also includes configuring a common uplink resource or a common uplink resource set for sharing between the UE and one or more UEs in the same cell as the UE 10. In some embodiments, the common uplink resource or the common uplink resource set is configured to the UE using cell-specific network RRC signaling. In some embodiments, the common uplink resource or the common uplink resource set includes PRACH resources and / or RA preambles. In some embodiments, the RA preamble includes a sequence-based RA preamble.

[0040] In some embodiments, a sequence-based RA preamble is used to represent NACK-only information, and the NACK-only information is used for HARQ feedback in the form of NACK-only reporting in the PRACH resources of the random access channel RACH opportunity. In some embodiments, the HARQ feedback in the form of NACK-only reporting in the PRACH resources of the RACH opportunity corresponds to the best SSB of the UE. In some embodiments, the method also includes determining the SSB index and / or frame timing of the best SSB in part through PBCH DMRS and / or PBCH data. In some embodiments, the method also includes transmitting the PRACH / RA preamble on a configured PRACH resource associated with the best SSB index and / or frame timing. In some embodiments, the association between the SSB or subset of PRACH resources and / or preamble indexes in the SS burst set is configured by a parameter set in the system information.

[0041] In some embodiments, the method further includes transmitting an RA preamble to notify the base station of the best SSB by using a RACH opportunity corresponding to the best SSB and a common NACK-only PRACH resource. In some embodiments, the method further includes receiving a retransmission of an MBS TB from the base station. In some embodiments, the retransmission of the MBS TB is transmitted via a unicast PDSCH. In some embodiments, the UE is located in a specific group associated with the detected RACH opportunity / SSB beam. In some embodiments, a RACH opportunity is a common PRACH resource / sequence for HARQ feedback in the form of NACK-only reporting, and is shared or used by the UE or one or more UEs in the same cell as the UE.

[0042] In some embodiments, the method further comprises calculating a transmit power for transmitting the RA preamble based on a downlink path loss of the RA preamble and a target received power. In some embodiments, the target received power is configured by the base station. In some embodiments, a range of transmit power levels corresponding to different downlink RSRP thresholds is configured by the base station, and the UE selects an appropriate power level from the range of transmit power levels based on the measured downlink RSRP level to transmit HARQ feedback in the form of NACK-only reporting.

[0043] In some embodiments, in a method of the present invention for a UE in an RRC idle or inactive state (or even in a connected state) to provide HARQ feedback to its resident station or base station (e.g., serving cell gNodeB (gNB)) in a 5G-NR network, the UE sends NACK reporting only for erroneously decoded TBs carried in the PDSCH. For the proposed NACK-only based HARQ reporting scheme, even when a PDSCH data packet TB is successfully decoded, or when the UE completely misses or fails to decode data scheduling downlink control information (DCI), the UE does not send any other HARQ reporting back to its serving / resident gNB, such as an acknowledgment (ACK) or during discontinuous transmission (DTX). Therefore, the main purpose of the NACK-only reporting from at least an RRC idle / inactive UE is to indicate to the gNB that it failed to decode the last transmitted TB in the DL.

[0044] Since the number of RRC Idle and Inactive UEs receiving the same MBS TBs may be very high and even unpredictable, accurately counting the number of NACK reports received or the number of UEs providing their HARQ feedback is not important or sometimes impossible. For the gNB to provide MBS services and meet the service requirements, it is sufficient for the gNB to only estimate a rough percentage or fraction of UEs that failed to decode an MBS TB transmitted in DL and provide one (or more) retransmissions of the same TB if the estimated percentage is higher than the requirement.

[0045] In one embodiment of the present invention, for unsuccessful / failed decoding of MBS TBs received in PDSCH (e.g., when the cyclic redundancy check (CRC) of the associated scheduling DCI is scrambled by the groupcast-radio network temporary identifier (G-RNTI)), the method by which the UE provides its NACK feedback reporting is to select a RA preamble using PRACH and transmit it to the network / its resident or serving gNB. Since the gNB only needs to know whether it should retransmit the same MBS TB in the downlink, the UE does not send an acknowledgement (ACK) response in case of successful decoding. Therefore, even if the gNB only sends and receives one NACK, the same TB can be retransmitted again.

[0046] In some embodiments, the method by which the UE selects an RA preamble is by first measuring the downlink RSRP using the primary synchronization signal (PSS), secondary synchronization signal (SSS) and / or PBCH DMRS to identify the best SSB within the SS burst set. The SSB corresponding to the highest measured downlink RSRP is the UE's best SSB and its associated SSB index / transmit beam. By using the RACH opportunity associated with that SSB index / beam and transmitting the RA preamble configured by the network gNB, the UE will be able to notify its gNB of the NACK response for the MBS TB received on that beam.

[0047] In turn, the gNB will also know the beam used for the last failed decoded MBS TB and subsequently provide retransmissions of the same MBS TB to the UE on the same beam. In detail, in some embodiments, the UE determines the SSB index and / or frame timing of the best SSB in part through the PBCH DMRS and / or PBCH data. The UE transmits a PRACH / RA preamble on the configured PRACH resources associated with the best SSB index and / or frame timing. The association between the SSBs or subsets of PRACH resources and / or preamble indices in an SS burst set is configured by a set of parameters in the system information. The UE transmits a RA preamble to inform the gNB of the best SSB by using the RACH opportunity corresponding to the best SSB and the common NACK-only PRACH resources. The gNB can perform retransmissions of MBS data TBs to a specific group of UEs associated with the detected RACH opportunity / SSB beam via downlink unicast DL-SCH (PDSCH). A RACH opportunity is a common PRACH resource / sequence used for NACK-only HARQ reporting and can be shared or used by one or more UEs.

[0048] In another embodiment of the present invention, a method is proposed for an RRC idle / inactive UE to determine its power level to transmit HARQ feedback reports for selected PRACH resources and RA preambles. In normal operation of a 5G-NR cellular communication network, power control commands (PCC) are provided to RRC connected UEs in a network cell, respectively, for their almost all signal and channel transmissions in the UL (except for the physical random access channel), so that the received power at the gNB between different transmitting UEs is at a similar level to avoid in-band emission (IBE) interference between adjacent frequency RBs and inter-UE interference when they are code division multiplexed (CDMed). This is particularly important for the proposed HARQ feedback when the gNB attempts to count the number of NACK reports based on the total received power of each PRACH resource. In order to ensure that the HARQ feedback of RRC idle / inactive UEs is transmitted using an appropriate power level, one of the following methods or a combination of more than one method should be used to accommodate different operating scenarios.

[0049] In some embodiments, an open-loop power control (OLPC) based approach: Since RRC idle / inactive UEs do not transmit any signals and channels in the UL (except for mobility location updates), if the idle / inactive UE does not leave its current serving location area, the UE will not receive any power control commands directly from the camping / serving gNB in ​​idle and inactive states. In the absence of an explicit indication of the power level for UL transmission from the gNB, the RRC idle / inactive UE derives the transmit power level for HARQ feedback reporting based on the OLPC scheme. In some embodiments, in the proposed OLPC for HARQ feedback reporting, the gNB configures a target receive power for the RA preamble. The UE determines / derives / calculates the power that the UE should use to transmit the RA preamble to the gNB based on the knowledge of the target receive power (X) and the estimated downlink path loss (Y) based on the best SSB measurement by simply using (X+Y). This can provide accurate power.

[0050] In some embodiments, a method based on RSRP threshold: As an alternative to the above-mentioned OLPC method based on target received power, a derivation based on RSRP threshold can be used to determine the Tx power for transmitting the RA preamble. In the RSRP threshold-based scheme, a range of transmit power levels corresponding to different RSRP thresholds is configured for the UE through the cell-common RRC configuration, and the UE selects a suitable power level from the indicated power range for transmitting the HARQ feedback report according to its measured downlink RSRP level.

[0051] In some embodiments, network configuration details are provided as follows.

[0052] The cell-specific random access parameter configuration (common to all UEs in the cell) for HARQ reporting via network RRC includes one or more of the following.

[0053] 1. Subcarrier spacing (SCS) for PRACH and / or BWP information. 2. Time and frequency information for each RACH opportunity and / or PRACH resource. 3. Number of RA preambles per SSB. 4. PRACH format, preamble sequence and / or root sequence index. 5. Information related to mapping PRACH resources / RA preambles to groupcast-RNTI (G-RNTI). 6. RSRP threshold for UE selection of SSB and corresponding PRACH for path loss estimation and (re)transmission based on SSBs that meet this threshold. 7. Target received power of RA preamble. 8. Power offset / threshold for preamble power setting.

[0054] In summary, in some embodiments, in order for the gNB of 5G-NR to provide at least one (or more) retransmissions of the necessary downlink MBS TBs to UEs in RRC idle and / or inactive states, HARQ feedback in the form of NACK-only reports from one (or more) UEs that are erroneously decoded should be sent to the gNB. That is, when the received TB is successfully decoded, the UE does not feedback any ACK report to minimize the number of feedback resources required and save UE processing and UL transmission. In order to further improve the utilization efficiency of the system's UL resources, one or a group of common uplink resources are shared among the receiving UEs of the MBS, that is, the PRACH resources and RA preambles are configured to the UEs using cell-specific network RRC signaling. In order to simplify the receiver detection process at the gNB, the sequence-based RA preamble indicating NACK-only information is used to feedback the HARQ report in the PRACH resource corresponding to the RACH opportunity of the UE's best SSB. The UE determines the SSB index and / or frame timing of the best SSB in part through the PBCH DMRS and / or PBCH data. The UE transmits a PRACH / RA preamble on the configured PRACH resources associated with the best SSB index and / or frame timing. The association between the SSBs or subsets of PRACH resources and / or preamble indices in an SS burst set is configured by a set of parameters in the system information. The UE transmits a RA preamble to inform the gNB of the best SSB by using the RACH opportunity corresponding to the best SSB and the common NACK-only PRACH resource. The gNB may perform retransmission of MBS data TBs to a specific group of UEs associated with the detected RACH opportunity / SSB beam via downlink unicast DL-SCH (PDSCH). A RACH opportunity is a common PRACH resource / sequence used for NACK-only HARQ reporting and may be shared or used by one or more UEs.

[0055] In summary, in some embodiments, to ensure that all UEs reporting HARQ use appropriate power levels so that the received power of their transmission sequences at the gNB is at a similar level, one or a combination of the following methods should be used to adapt to different operating scenarios. Open-loop power control based method: Based on the network configured target received power at the gNB and the estimated DL path loss at the UE, the UE calculates the transmit power for transmitting the RA preamble as the DL path loss and the target received power. RSRP threshold based method: A range of transmit power levels corresponding to different RSRP thresholds is configured, and the UE selects an appropriate power level from the indicated power range for transmitting the HARQ feedback report based on its measured downlink RSRP level.

[0056] The commercial benefits of some embodiments are as follows. 1. Solve problems in the prior art. 2. Reduce the number of required feedback resources. 3. Save UL transmissions for UE processing. 4. Provide more reliable MBS data reception with lower latency. 5. Provide a better user experience. 6. Provide good communication performance. 7. Provide high reliability. 8. Some embodiments of the present disclosure may be used by: 5G-NR chipset suppliers, V2X communication system development suppliers, automobile manufacturers including cars, trains, trucks, buses, bicycles, motorcycles, helmets, etc., drones (unmanned aerial vehicles), smartphone manufacturers, communication devices for public safety use, augmented reality / virtual reality (AR / VR) device manufacturers (e.g., games, conferences / seminars, educational purposes). Some embodiments of the present disclosure are combinations of "techniques / processes" that can be adopted in 3GPP specifications to create a final product.

[0057] Figure 4 is a block diagram of an example system 700 for wireless communications according to an embodiment of the present disclosure. The embodiments described herein may be implemented into a system using any suitably configured hardware and / or software. Figure 4 A system 700 is shown, which includes at least Figure 4 A radio frequency (RF) circuit 710, a baseband circuit 720, an application circuit 730, a memory / storage 740, a display 750, a camera 760, a sensor 770, and an input / output (I / O) interface 780 are shown coupled to each other.

[0058] Application circuit 730 may include, for example, but not limited to, circuits of one or more single-core or multi-core processors. The processor may include any combination of general-purpose processors and special-purpose processors, such as a graphics processor, an application processor. The processor may be coupled to a memory / storage and configured to execute instructions stored in the memory / storage to implement various applications and / or operating systems running on the system.

[0059] The baseband circuit 720 may include, for example, but not limited to, circuits of one or more single-core or multi-core processors. The processor may include a baseband processor. The baseband circuit may handle various wireless control functions that can communicate with one or more wireless networks via a radio frequency circuit. The wireless control functions may include, but are not limited to, signal modulation, encoding, decoding, radio frequency shifting, etc. In some embodiments, the baseband circuit may provide communications compatible with one or more wireless technologies. For example, in some embodiments, the baseband circuit may support communications with an evolved universal terrestrial radio access network (EUTRAN) and / or other wireless metropolitan area networks (WMAN), wireless local area networks (WLAN), and wireless personal area networks (WPAN). An embodiment in which the baseband circuit is configured to support wireless communications of more than one wireless protocol may be referred to as a multi-mode baseband circuit.

[0060] In various embodiments, baseband circuitry 720 may include circuitry for operating with signals that are not strictly considered to be at baseband frequencies. For example, in some embodiments, baseband circuitry may include circuitry for operating with signals having an intermediate frequency between baseband frequencies and radio frequencies.

[0061] The radio frequency circuit 710 may use modulated electromagnetic radiation through a non-solid medium to enable communication with a wireless network. In various embodiments, the radio frequency circuit may include switches, filters, amplifiers, etc. to facilitate communication with a wireless network.

[0062] In various embodiments, RF circuitry 710 may include circuitry that operates using signals that are not strictly considered to be in radio frequencies. For example, in some embodiments, RF circuitry may include circuitry for operating using signals having an intermediate frequency between baseband frequencies and radio frequencies.

[0063] In various embodiments, the transmit circuit, control circuit, or receive circuit discussed above with respect to a user equipment, eNB, or gNB may be embodied in whole or in part in one or more of a radio frequency circuit, a baseband circuit, and / or an application circuit. As used herein, "circuitry" may refer to, belong to, or include an application specific integrated circuit (ASIC), electronic circuit, processor (shared, dedicated, or group), and / or memory (shared, dedicated, or group) that executes one or more software or firmware programs, combinational logic circuits, and / or other suitable hardware components that provide the described functionality. In some embodiments, electronic device circuits may be implemented in one or more software or firmware modules, or the functionality associated with the circuits may be implemented by one or more software or firmware modules.

[0064] In some embodiments, some or all components of the baseband circuit, application circuit and / or memory / storage may be implemented together on a system on a chip (SOC).

[0065] The memory / storage 740 may be used to load and store, for example, data and / or instructions for the system. The memory / storage for one embodiment may include any combination of suitable volatile memory (e.g., dynamic random access memory (DRAM)) and / or non-volatile memory (e.g., flash memory).

[0066] In various embodiments, I / O interface 780 may include one or more user interfaces and / or peripheral component interfaces, wherein the user interface is designed to enable a user to interact with the system, and the peripheral component interface is designed to enable a peripheral component to interact with the system. The user interface may include, but is not limited to, a physical keyboard or keypad, a touch pad, a speaker, a microphone, etc. The peripheral component interface may include, but is not limited to, a non-volatile memory port, a universal serial bus (USB) port, an audio jack, and a power interface.

[0067] In various embodiments, the sensor 770 may include one or more sensing devices to determine environmental conditions and / or location information related to the system. In some embodiments, the sensor may include, but is not limited to, a gyroscope sensor, an accelerometer, a proximity sensor, an ambient light sensor, and a positioning unit. The positioning unit may also be part of the baseband circuit and / or the radio frequency circuit, or interact with the baseband circuit and / or the radio frequency circuit to communicate with components of a positioning network (e.g., a global positioning system (GPS) satellite).

[0068] In various embodiments, the display 750 may include a display such as a liquid crystal display and a touch screen display. In various embodiments, the system 700 may be a mobile computing device such as, but not limited to, a laptop computer device, a tablet computer device, a netbook, an ultrabook, a smart phone, AR / VR glasses, etc. In various embodiments, the system may have more or fewer components and / or different architectures. Where appropriate, the methods described herein may be implemented as a computer program. The computer program may be stored on a storage medium such as a non-transitory storage medium.

[0069] Those skilled in the art will appreciate that each unit, algorithm, and step described and disclosed in the embodiments of the present disclosure is implemented using electronic hardware or a combination of computer and electronic hardware software. Whether a function is run in hardware or software depends on the application conditions and the design requirements of the technical plan.

[0070] A person skilled in the art may use different methods to implement the functions of each specific application, and such implementation should not exceed the scope of the present disclosure. A person skilled in the art understands that since the working processes of the above-mentioned systems, devices and units are basically the same, he / she may refer to the working processes of the systems, devices and units in the above-mentioned embodiments. For ease of description and simplification, these working processes will not be described in detail.

[0071] It is understood that the systems, devices and methods disclosed in the embodiments of the present disclosure may be implemented in other ways. The above embodiments are exemplary only. The division of units is based solely on logical functions, and other divisions exist in the implementation. Multiple units or components may be combined or integrated in another system. Certain features may also be omitted or skipped. On the other hand, the interconnected, directly coupled or communicatively coupled shown or discussed operates through some ports, devices or units, whether indirectly or communicatively by means of electrical, mechanical or other types of forms.

[0072] The units used as separate components for explanation may or may not be physically separate. The units used for display may or may not be physical units, i.e., located in one place or distributed over multiple network units. Some or all of the units are used according to the purpose of the embodiment. In addition, the functional units in the various embodiments may be integrated into one processing unit, physically independent, or integrated into one processing unit having two or more units.

[0073] If the software functional unit is implemented, used and sold as a product, it can be stored in a readable storage medium in a computer. Based on this understanding, the technical solution proposed in the present disclosure can be implemented substantially or partially in the form of a software product. Alternatively, a part of the technical solution that is beneficial to traditional technology can be implemented in the form of a software product. The software product in the computer is stored in a storage medium, including multiple commands for a computing device (such as a personal computer, a server or a network device) to run all or some steps disclosed in the embodiment of the present disclosure. The storage medium includes a USB disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a floppy disk or other types of media capable of storing program code.

[0074] While the present disclosure describes what are considered to be the most practical and preferred embodiments, it is to be understood that the disclosure is not limited to the disclosed embodiments but is intended to cover various arrangements pursuant to the broadest interpretation of the appended claims.

Claims

1. A user equipment UE, comprising: Memory; Transceiver; as well as a processor coupled to the memory and the transceiver; wherein, The transceiver is configured to receive a multicast broadcast service MBS transport block TB from a base station; The processor is configured to decode the MBS TB; and When the processor erroneously decodes the MBS TB, the transceiver transmits a hybrid automatic repeat request HARQ feedback in a negative acknowledgement (NACK-only) reporting form to the base station.

2. The UE according to claim 1, wherein: When the processor successfully decodes the MBS TB, the transceiver does not feed back any ACK report to the base station.

3. The UE according to claim 1 or 2, wherein: The processor is configured with a common uplink resource or a set of common uplink resources for sharing between the UE and one or more UEs.

4. The UE according to claim 3, wherein: The common uplink resource or the set of common uplink resources is configured to the processor using cell-specific network RRC signaling.

5. A method for hybrid automatic repeat request (HARQ) feedback transmission of a user equipment (UE), the method comprising: Receiving a multicast broadcast service MBS transport block TB from a base station; Decoding the MBS TB; as well as When the UE erroneously decodes the MBS TB, it transmits HARQ feedback in the form of a negative acknowledgement (NACK)-only report to the base station.

6. The method according to claim 5, wherein: When the UE successfully decodes the MBS TB, the UE does not feed back any positive acknowledgement ACK report to the base station.

7. The method according to claim 5 or 6, further comprising configuring a common uplink resource or a set of common uplink resources for sharing between the UE and one or more UEs.

8. The method according to claim 7, wherein: The common uplink resource or the set of common uplink resources is configured to the UE using cell-specific network RRC signaling.

9. A base station, comprising: Memory; Transceiver; as well as a processor coupled to the memory and the transceiver; wherein: The transceiver is configured to transmit a multicast broadcast service MBS transport block TB to a user equipment UE; as well as When the UE erroneously decodes the MBS TB, the transceiver receives a hybrid automatic repeat request (HARQ) feedback in the form of a negative acknowledgement (NACK-only) reporting from the UE.

10. The base station according to claim 9, wherein: When the UE successfully decodes the MBS TB, the UE does not feed back any positive acknowledgement ACK report to the base station.

11. The base station according to claim 9 or 10, wherein: The processor configures, to the UE, a common uplink resource or a set of common uplink resources for sharing between the UE and one or more UEs.

12. The base station according to claim 11, wherein: The common uplink resource or the set of common uplink resources is configured to the UE using cell-specific network RRC signaling.

13. A method for hybrid automatic repeat request (HARQ) feedback transmission of a base station, the method comprising: Transmitting a multicast broadcast service MBS transport block TB to a user equipment UE; as well as When the UE erroneously decodes an MBS TB, HARQ feedback in the form of a negative acknowledgement (NACK)-only reporting is received from the UE.

14. The method according to claim 13, wherein: When the UE successfully decodes the MBS TB, the UE does not feed back any positive acknowledgement ACK report to the base station.

15. The method according to claim 13 or 14, further comprising configuring the UE with a common uplink resource or a set of common uplink resources for sharing between the UE and one or more UEs.

16. The method according to claim 15, wherein: The common uplink resource or the set of common uplink resources is configured to the UE using cell-specific network RRC signaling.

17. A chip, comprising: A processor, configured to call and run a computer program stored in a memory so that a device equipped with the chip executes a method as claimed in any one of claims 5 to 8 and 13 to 16.

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