CN115484672A

CN115484672A - HARQ-ACK feedback method and system

Info

Publication number: CN115484672A
Application number: CN202110599165.5A
Authority: CN
Inventors: 魏立梅; 陈迎; 范晨; 朱玉梅; 周志宏; 袁乃华
Original assignee: Chengdu TD Tech Ltd
Current assignee: Chengdu TD Tech Ltd
Priority date: 2021-05-31
Filing date: 2021-05-31
Publication date: 2022-12-16

Abstract

The application provides a HARQ-ACK feedback method and a system, which are used for ensuring that the receiving of MBS conversation by user equipment meets the reliability requirement. The method comprises the following steps: the base station generates resource configuration information of the MBS conversation, wherein the resource configuration information comprises configuration information of each PTM bearing and configuration information of a group of PUCCHs of each PTM bearing; the base station sends the resource configuration information to the user equipment; the user equipment receives the resource configuration information and establishes a PTM bearer according to the configuration information of the PTM bearer; the base station sends a first TB through a first PTM bearer; the user equipment receives the first TB through a first PTM bearer; the user equipment determines that the first TB is decoded incorrectly, generates NACK information of the first TB, and feeds back the NACK information to the base station through a first PUCCH carried by the first PTM; the base station detects each PUCCH and retransmits the first TB.

Description

HARQ-ACK feedback method and system

Technical Field

The present application relates to the field of communications technologies, and in particular, to a HARQ-ACK feedback method and system.

Background

With the continuous development of wireless communication technology, new Radio Access (NR) systems have come into people's lives. To provide Multicast and Broadcast Service (MBS) in NR cells, work Item (Work Item, WI) was set up at Release 17 (Release 17, R17) over The Radio Access Network (RAN) of The third Generation Partnership project (3 gpp) at 12 months in 2019: NR MBS.

The service type that MBS can provide is the same as the service type that unicast service can provide, and for the same service type, MBS and unicast service have the same QOS requirement. At present, it is a technical problem to be solved urgently to improve the receiving performance of Radio Resource Control Connected (RRC _ Connected) UE to MBS, and ensure that the receiving of MBS by UE meets the reliability requirement of MBS.

Disclosure of Invention

The embodiment of the application provides a HARQ-ACK feedback method and a system. The reliability requirement of the MBS on the receiving of the UE can be ensured to meet.

In a first aspect, an embodiment of the present application provides a HARQ-ACK feedback method, where the method includes: the base station allocates wireless resources to the MBS conversation and generates resource allocation information of the MBS conversation, wherein the resource allocation information of the MBS conversation comprises: configuration information of each point-to-multipoint PTM bearer of the MBS session and configuration information of a group of physical uplink control channels PUCCH of each PTM bearer; the base station sends the resource allocation information of the MBS conversation to the user equipment; the user equipment receives the resource configuration information of the MBS conversation sent by the base station, saves the resource configuration information of the MBS conversation, establishes a corresponding PTM bearing according to the configuration information of each PTM bearing in the resource configuration information of the MBS conversation, and receives the MBS conversation through the established PTM bearing; the base station generates a first transmission block TB of the MBS conversation, and sends the first TB to the user equipment through a first PTM bearer in the PTM bearer, wherein the first TB is assembled by data on an RB transmitted through the first PTM bearer in a radio bearer RB of the MBS conversation; the user equipment receives each TB of the MBS conversation from the base station through the established PTM bearing, wherein each TB of the MBS conversation comprises the first TB; the user equipment determines that the received first TB is decoded incorrectly, the user equipment generates non-acknowledgement (NACK) information of the first TB, and feeds back the NACK information of the first TB to the base station through a first PUCCH in a group of PUCCHs carried by the first PTM, wherein the NACK information of the first TB is used for retransmitting the first TB by the base station; and the base station detects each PUCCH in a group of PUCCHs configured for the first PTM bearer, and performs retransmission scheduling of the first TB and/or performs initial transmission scheduling on subsequent TBs according to the detection result.

Optionally, the configuration information of a group of PUCCHs carried by the PTM includes: a number of PUCCHs in the set of PUCCHs; a format of each PUCCH in the set of PUCCHs, wherein the format of each PUCCH in the set of PUCCHs is any one of the following formats: PUCCH format 0, PUCCH format 1, PUCCH format 2, PUCCH format 3, and PUCCH format 4.

Optionally, the configuration information of a group of PUCCHs carried by the PTM further includes: and the channel quality indication CQI range corresponding to each PUCCH in the set of PUCCHs.

Optionally, the CQI range corresponding to each PUCCH in the group of PUCCHs is determined according to any one of the following methods: configuring a modulation and coding method MCS index range for each PUCCH in the group of PUCCHs, wherein the MCS index ranges corresponding to different PUCCHs are not overlapped; or, each PUCCH in the set of PUCCHs corresponds to a dynamic MCS index range, and the dynamic MCS index ranges corresponding to different PUCCHs are not overlapped; or, each PUCCH in the set of PUCCHs is assigned a CQI index range, and the CQI index ranges corresponding to different PUCCHs do not overlap.

Optionally, a bit sequence corresponding to the NACK information is defined as a sequence with a fixed length in a 3GPP NR protocol, and a value of each bit in the bit sequence corresponding to the NACK information is fixed.

Optionally, a generation formula of a bit sequence corresponding to the NACK information is defined in a 3GPP NR protocol, where the bit sequence corresponding to the NACK information is generated by the generation formula, and the generation formula includes a generation parameter of the bit sequence corresponding to the NACK information.

Optionally, the generating formula includes any one of: the bit sequence corresponding to the NACK information is as follows: a full 0 sequence with a length of L1, wherein L1 is a generation parameter of a bit sequence corresponding to the NACK information; or the like, or, alternatively,

the bit sequence corresponding to the NACK information is as follows: a full 1 sequence with a length of L1, wherein L1 is a generation parameter of a bit sequence corresponding to the NACK information; or the like, or a combination thereof,

the bit sequence corresponding to the NACK information is generated by a pseudo-random sequence generation formula, which includes two parameters: and the length of the pseudo-random sequence and the initialization value of the pseudo-random sequence are generation parameters of a bit sequence corresponding to the NACK information.

Optionally, if at least one PUCCH in a group of PUCCHs carried by the PTM adopts PUCCH format 2/3/4, the configuration information of the group of PUCCHs carried by the PTM further includes: and generating parameters of a bit sequence corresponding to the NACK information.

Optionally, before the ue feeds back the NACK information of the first TB to the base station through a first PUCCH in a group of PUCCHs carried by the first PTM, the method further includes: the user equipment determines the first PUCCH from a group of PUCCHs carried by the first PTM, and the measurement result of the CQI of the user equipment is contained in a CQI range corresponding to the first PUCCH.

Optionally, when the first PUCCH adopts PUCCH format 0/1, the ue feeds back NACK information of the first TB to the base station through the first PUCCH, where the NACK information includes: and the user equipment feeds back the NACK information of the first TB to the base station through the first PUCCH.

Optionally, when the first PUCCH adopts PUCCH format 2/3/4, the ue feeds back NACK information of the first TB to the base station through the first PUCCH, where the NACK information includes: and the user equipment feeds back a bit sequence corresponding to the NACK information of the first TB to the base station through the first PUCCH, wherein the bit sequence corresponding to the NACK information of the first TB is a sequence with fixed length.

Optionally, when the first PUCCH adopts PUCCH format 2/3/4, the ue feeds back NACK information of the first TB to the base station through the first PUCCH, where the NACK information includes: the user equipment generates a first bit sequence according to a generation formula of a bit sequence corresponding to the NACK information and generation parameters of the bit sequence corresponding to the NACK information; and the user equipment feeds back the first bit sequence to the base station through the first PUCCH.

Optionally, the performing, by the base station, retransmission scheduling of the first TB and/or initial transmission scheduling of subsequent TBs according to the detection result includes: when the base station detects at least one PUCCH, the base station determines the channel quality condition of user equipment feeding back the PUCCH according to the CQI range respectively corresponding to the at least one PUCCH for each detected PUCCH, summarizes the detected CQI range corresponding to each PUCCH, and performs retransmission scheduling on the first TB and initial transmission scheduling on subsequent TBs; and when the base station does not detect any PUCCH, the base station performs initial transmission scheduling on the subsequent TB.

In a second aspect, another HARQ-ACK feedback method is provided, where the method is applied to a base station, and the method includes:

the base station allocates wireless resources to the MBS conversation and generates resource allocation information of the MBS conversation, wherein the resource allocation information of the MBS conversation comprises: configuration information of each point-to-multipoint PTM bearer of the MBS session and configuration information of a group of physical uplink control channels PUCCH of each PTM bearer;

the base station sends the resource allocation information of the MBS conversation to the user equipment;

the base station generates a first transmission block TB of the MBS conversation, and sends the first TB to the user equipment through a first PTM bearer in the PTM bearers, wherein the first TB is formed by assembling data on an RB transmitted through the first PTM bearer in a radio bearer RB of the MBS conversation;

and the base station detects each PUCCH in a group of PUCCHs configured for the first PTM bearer, and performs retransmission scheduling of the first TB and/or performs initial transmission scheduling on subsequent TBs according to the detection result.

In a third aspect, another HARQ-ACK feedback method is provided, where the method is applied to a user equipment, and the method includes:

the user equipment receives the resource configuration information of the MBS conversation sent by the base station, saves the resource configuration information of the MBS conversation, establishes a corresponding PTM bearing according to the configuration information of each PTM bearing in the resource configuration information of the MBS conversation, and receives the MBS conversation through the established PTM bearing;

the user equipment receives each TB of the MBS conversation from the base station through the established PTM bearing, wherein each TB of the MBS conversation comprises the first TB;

the user equipment determines that the received first TB is decoded incorrectly, the user equipment generates non-acknowledgement (NACK) information of the first TB, the user equipment feeds back the NACK information of the first TB to the base station through a first PUCCH in a group of PUCCHs carried by the first PTM, and the NACK information of the first TB is used for the base station to retransmit the first TB.

In a fourth aspect, an embodiment of the present application provides a HARQ-ACK feedback system, where the system includes:

a base station, configured to configure wireless resources for a multicast broadcast service MBS session, and generate resource configuration information of the MBS session, where the resource configuration information of the MBS session includes: configuration information of each point-to-multipoint PTM bearer of the MBS session and configuration information of a group of physical uplink control channels PUCCH of each PTM bearer;

the base station is also used for sending the resource configuration information of the MBS conversation to the user equipment;

the user equipment is used for receiving the resource configuration information of the MBS conversation sent by the base station, saving the resource configuration information of the MBS conversation, establishing corresponding PTM bearing according to the configuration information of each PTM bearing in the resource configuration information of the MBS conversation, and receiving the MBS conversation through the established PTM bearing;

the base station is further configured to generate a first transport block TB of the MBS session, send the first TB to the user equipment through a first PTM bearer in the PTM bearer, where the first TB is assembled from data on an RB transmitted through the first PTM bearer in a radio bearer RB of the MBS session;

the user equipment is further configured to receive each TB of the MBS session from the base station through the established PTM bearer, where each TB of the MBS session includes the first TB;

the user equipment is further configured to determine that the received first TB is decoded in error, generate non-acknowledgement NACK information of the first TB, and feed back, by the user equipment, the NACK information of the first TB to the base station through a first PUCCH in a group of PUCCHs carried by the first PTM, where the NACK information of the first TB is used for the base station to retransmit the first TB;

the base station is further configured to detect each PUCCH in a group of PUCCHs configured for the first PTM bearer, and perform retransmission scheduling of the first TB and/or perform initial transmission scheduling on a subsequent TB according to a detection result.

Optionally, the CQI range corresponding to each PUCCH in the set of PUCCHs is determined according to any one of the following methods: configuring a modulation and coding method MCS index range for each PUCCH in the group of PUCCHs, wherein the MCS index ranges corresponding to different PUCCHs are not overlapped; or, each PUCCH in the set of PUCCHs corresponds to a dynamic MCS index range, and the dynamic MCS index ranges corresponding to different PUCCHs are not overlapped; or, each PUCCH in the set of PUCCHs is assigned a CQI index range, and the CQI index ranges corresponding to different PUCCHs do not overlap.

Optionally, the generating formula includes any one of the following: the bit sequence corresponding to the NACK information is as follows: a full 0 sequence with a length of L1, wherein L1 is a generation parameter of a bit sequence corresponding to the NACK information; or, the bit sequence corresponding to the NACK information is: a full 1 sequence with a length of L1, wherein L1 is a generation parameter of a bit sequence corresponding to the NACK information; or, the bit sequence corresponding to the NACK information is generated by a pseudo-random sequence generation formula, where the pseudo-random sequence generation formula includes two parameters: and the length of the pseudo-random sequence and the initialization value of the pseudo-random sequence are generation parameters of a bit sequence corresponding to the NACK information.

Optionally, the user equipment is further configured to determine the first PUCCH from a group of PUCCHs carried by the first PTM, and a measurement result of the CQI of the user equipment is included in a CQI range corresponding to the first PUCCH.

Optionally, when the first PUCCH adopts PUCCH format 0/1, the user equipment is specifically configured to: and feeding back the NACK information of the first TB to the base station through the first PUCCH.

Optionally, when the first PUCCH adopts PUCCH format 2/3/4, the user equipment is specifically configured to: feeding back a bit sequence corresponding to the NACK information of the first TB to the base station through the first PUCCH, wherein the bit sequence corresponding to the NACK information of the first TB is a sequence with a fixed length.

Optionally, when the first PUCCH adopts PUCCH format 2/3/4, the user equipment is specifically configured to: generating a first bit sequence according to a generation formula of a bit sequence corresponding to the NACK information and a generation parameter of the bit sequence corresponding to the NACK information; and feeding back the first bit sequence to the base station through the first PUCCH.

Optionally, the base station is specifically configured to: when at least one PUCCH is detected, determining the channel quality condition of user equipment feeding back the at least one PUCCH according to the CQI ranges respectively corresponding to the at least one PUCCH, summarizing the CQI ranges respectively corresponding to the at least one PUCCH, and performing retransmission scheduling on the first TB and initial transmission scheduling on subsequent TBs; and when any PUCCH is not detected, performing initial transmission scheduling on the subsequent TB.

In a fifth aspect, a communication device is provided, the communication device comprising: at least one processor and memory; the memory stores computer-executable instructions; the at least one processor executes the computer-executable instructions stored by the memory to cause the communication device to perform the method of the second aspect.

In a sixth aspect, there is provided a communication device comprising: at least one processor and memory; the memory stores computer-executable instructions; the at least one processor executes the computer-executable instructions stored by the memory to cause the communication device to perform the method of the third aspect.

In a seventh aspect, a computer-readable storage medium is provided, which stores a computer program (which may also be referred to as code or instructions) that, when executed on a computer, causes the computer to perform the method in any one of the above-mentioned first to third aspects or any one of the possible implementations of the first to third aspects.

In an eighth aspect, there is provided a computer program product comprising: a computer program (which may also be referred to as code, or instructions), which when executed by a processor, causes a computer to perform the method of any one of the possible implementations of the first to third aspects or the first to third aspects described above.

In the HARQ-ACK feedback method and system provided by the present application, a base station configures configuration information of a PTM bearer and configuration information of a PUCCH for a user equipment, the user equipment may establish the PTM bearer according to the configuration information of the PTM bearer to receive a first TB sent by the base station, if the user equipment decodes the received first TB incorrectly, the user equipment generates NACK information of the first TB, and may feed back the NACK information of the first TB to the base station through the first PUCCH in a group of PUCCHs configured by the base station, and the base station may retransmit according to the detected NACK information. The method can improve the reliability of data transmission, thereby ensuring that the receiving of the user equipment to the MBS meets the reliability requirement of the MBS.

Drawings

FIG. 1 is a schematic diagram of a communication system suitable for use in the present application;

fig. 2 is a schematic flow chart of a HARQ-ACK feedback method provided herein;

fig. 3 is a schematic block diagram of a system supporting a HARQ-ACK feedback method provided herein;

fig. 4 is a schematic structural diagram of a base station provided in the present application;

fig. 5 is a schematic structural diagram of a user equipment provided in the present application.

Detailed Description

In order to make the technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments that can be made by one skilled in the art based on the embodiments in the present application in light of the present disclosure are within the scope of the present application.

The terms "first," "second," "third," "fourth," and the like in the description and in the claims of the present application and in the drawings described above, if any, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the application described herein are capable of operation in sequences other than those illustrated or described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

The HARQ-ACK feedback method provided by the present application is applicable to the communication system shown in fig. 1. As shown in fig. 1, the communication system includes: a base station and a plurality of user equipments, wherein there are 4 user equipments: user equipment 1, user equipment 2, user equipment 3 and user equipment 4.

In WI NR MBS, a method of determining to provide a broadcast service and a multicast service in an NR cell is required. The method includes a number of key functions. One of the key functions is to satisfy the reliability requirement of MBS through Hybrid Automatic retransmission Request acknowledgement (HARQ-ACK) feedback.

In the NR cell, in order to improve the reliability of the unicast service, a HARQ-ACK feedback function is adopted. The function comprises the following two feedback modes:

(1) HARQ-ACK feedback based on acknowledgement/Non-acknowledgement (ACK/NACK).

In this feedback scheme, a User Equipment (UE) receives a Transport Block (TB) of a unicast service. If the UE correctly decodes the TB, generating Acknowledgement (ACK) information; otherwise, non-acknowledgement (NACK) information is generated. The UE feeds back ACK/NACK information of the TB to the gNB through a Physical Uplink Control Channel (PUCCH) allocated in advance. And the gNB receives ACK/NACK information fed back by the UE on a pre-allocated PUCCH. When the gNB receives the ACK information, the gNB sends the next TB; otherwise, the gNB retransmits the current TB, and the decoding performance of the UE on the current TB is improved through retransmission, so that the receiving performance of the UE on the unicast service can meet the reliability requirement of the unicast service. The reliability requirement of the unicast Service is embodied in the reliability requirement of the QOS (Quality of Service) requirement of the unicast Service.

(2) HARQ-ACK feedback based on Non-acknowledgement Only (NACK-ONLY).

In this feedback mode, the UE receives the TBs of the unicast service. If the UE correctly decodes the TB, the UE does not feed back any information to the gNB; otherwise, the UE generates NACK information and feeds back the NACK information of the TB to the gNB through a pre-allocated PUCCH. And the gNB receives NACK information fed back by the UE on a pre-allocated PUCCH. When receiving the NACK information, the gNB retransmits the current TB, and the decoding performance of the UE on the current TB is improved through retransmission, so that the receiving performance of the UE on the unicast service meets the reliability requirement of the unicast service.

The service type that MBS can provide is the same as the service type that unicast service can provide, and for the same service type, MBS and unicast service have the same QOS requirement. The difference is only that: unicast traffic is transmitted to a designated UE, while MBS is transmitted to a group of designated UEs or to all UEs in a cell.

The application provides a HARQ-ACK feedback method in NR MBS, which is used for improving the receiving performance of Radio Resource Control Connected (RRC _ CONNECTED) UE to the MBS and ensuring that the receiving of the UE to the MBS meets the reliability requirement of the MBS. Like unicast services, the reliability requirements of MBS are reflected in the reliability requirements in the QOS requirements of MBS.

A flowchart of an HARQ-ACK feedback method in NR MBS provided in the embodiment of the present application is shown in fig. 2. The specific method comprises the following steps:

for each MBS session, the gNB configures radio resources for the MBS session and generates resource configuration information of the MBS session, where the resource configuration information of the MBS session includes: configuration information of each Point-to-Multipoint (PTM) bearer configured for the MBS session, and configuration information of a set of Physical Uplink Control Channels (PUCCHs) configured for each PTM bearer.

Each MBS session may use a plurality of PTM bearers for transmitting data on respective Radio Bearers (RBs) of the MBS session, and the UE establishes the respective PTM bearers according to configuration information of the respective PTM bearers used by the MBS session to receive the MBS session. For each PTM bearer, the UE determines a group of PUCCHs according to configuration information of the group of PUCCHs configured for the PTM bearer, generates NACK information of the TBs when the UE decodes the TBs on the PTM bearer in error, and selects one PUCCH from the determined group of PUCCHs for feeding back the NACK information of the TBs on the PTM bearer to the gNB. Wherein each PTM bearer transmits data on a corresponding RB of the MBS session in a PTM manner.

For an MBS session transmitted to a set of designated RRC _ CONNECTED UEs, when the MBS session includes at least one RB of non-Semi-Persistent Scheduling (SPS), the gNB configures a Group-Radio Network Temporary Identifier (G-RNTI) for the MBS session, is configured to identify the non-SPS RBs of the MBS session at an air interface, configure a PTM bearer for the non-SPS RBs of the MBS session, and configure a set of PUCCHs for feeding back NACK information of the TBs on the PTM bearer.

When the MBS session comprises at least one SPS RB, configuring a Group-Configured Scheduling-Radio Network Temporary Identifier (G-CS-RNTI) for the MBS session, identifying the SPS RBs of the MBS session at an air interface, configuring a PTM bearer for each SPS RB, transmitting data on the SPS RBs, and configuring a Group of PUCCHs for feeding back NACK information of TBs on the PTM bearer for the PTM bearer.

For SPS RBs with the same periodicity, optionally, a PTM bearer is configured uniformly for these RBs for transmitting data on these RBs, and a set of PUCCHs is configured for the uniformly configured PTM bearer for feeding back NACK information of TBs on the PTM bearer.

In the practical application of the HARQ-ACK feedback method in NR MBS provided in the present application, one MBS session usually includes multiple RBs. Accordingly, a scenario in which a PTM bearer is configured for an MBS session and a set of PUCCHs is pre-configured for each PTM bearer may be subdivided as follows. Under each subdivided scenario, the method of the present application is detailed as follows:

scene one: all RBs included in the MBS session are non-SPS RBs.

When all RBs included in the MBS session are non-SPS RBs, the gNB transmits data on the RBs in a dynamic scheduling mode. The gNB only needs to configure a PTM bearer for all the non-SPS RBs of the MBS session, and pre-configures a group of PUCCHs for the PTM bearer, wherein the PTM bearer is used for transmitting data on all the non-SPS RBs of the MBS session, the group of PUCCHs is used for the UE to feed back NACK information of a TB on the PTM bearer to the gNB, and the TB is formed by assembling the data on all the non-SPS RBs of the MBS session. Wherein the set of PUCCHs includes at least one PUCCH.

Scene two: the MBS session contains only one SPS RB.

And when the MBS session only comprises one SPS RB, the gNB transmits the data on the SPS RB in a semi-persistent scheduling mode. And the gNB only needs to configure a PTM bearer for the SPS RB of the MBS conversation and pre-configures a group of PUCCHs for the PTM bearer, wherein the PTM bearer is used for transmitting data on the SPS RB of the MBS conversation, the group of PUCCHs are used for feeding NACK information of a TB (negative acknowledgement) on the PTM bearer back to the gNB by the UE, and the TB is formed by assembling the data on the SPS RB. Wherein the set of PUCCHs includes at least one PUCCH.

Scene three: an MBS session includes at least one non-SPS RB and/or at least one SPS RB.

(1) When the MBS session contains at least one non-SPS RB, the gNB performs the following:

for all non-SPS RBs, the gbb transmits data on these RBs in a dynamically scheduled manner. The gNB only needs to configure a PTM bearer for the non-SPS RBs of the MBS session, the PTM bearer is used for transmitting data on the RBs, a group of PUCCHs is configured for the PTM bearer, the UE feeds back NACK information of a TB on the PTM bearer to the gNB, and the TB is formed by assembling the data on all the non-SPS RBs.

(2) When the MBS session contains at least one SPS RB, the gNB performs the following:

for each SPS RB, the gNB configures a PTM bearer for the RB, the PTM bearer is used for transmitting data on the RB, a group of PUCCHs are pre-configured for the PTM bearer, the UE feeds back NACK information of a TB on the PTM bearer to the gNB, and the TB is formed by assembling the data on the SPS RB. Each SPS RB has one and only one PTM bearer, and has one and only one set of preconfigured PUCCHs.

For SPS RBs with the same period, optionally, a PTM bearer is configured uniformly for the RBs to transmit data on the RBs, and a set of PUCCHs is configured in advance for the UE to feed back NACK information of TBs on the PTM bearer, where the TBs are assembled from the data on the SPS RBs.

In the method, a group of PUCCHs is pre-configured for the MBS, and RRC _ CONNECTED UEs receiving the MBS share the group of PUCCHs, so that PUCCH resources required for feeding back NACK information are reduced as much as possible, and interference of the PUCCHs feeding back the NACK information on other channels and adjacent cell channels of the cell is reduced and dispersed as much as possible.

In the 3GPP NR protocol, the PUCCH is used to feed Uplink Control Information (UCI) back to the gNB. There are five formats for PUCCH, including: format 0, format 1, format 2, format 3 and format 4. The length of UCI which can be transmitted by PUCCH format 0/1 is L =1 or L =2, UCI information is directly modulated into a symbol, and then the modulated symbol is sent to gNB through PUCCH; the length L of UCI information which can be transmitted by PUCCH format 2/3/4 is more than 2, the UCI information is firstly subjected to channel coding, then a bit sequence output by the channel coding is modulated, and finally a symbol sequence obtained by modulation is sent to the gNB through PUCCH format 2/3/4.

In summary, PUCCH format 0/1 does not employ channel coding, and PUCCH format 2/3/4 employs channel coding. Generally, the PUCCH format 2/3/4 can provide better coverage than PUCCH format 0/1, and the performance of detecting PUCCH format 2/3/4 using channel coding by the gNB is higher.

In this application, each PUCCH in a preconfigured set of PUCCHs may adopt the same PUCCH format or different PUCCH formats. Specifically, each PUCCH in the group may be in format 0, format 1, format 2, format 3, or format 4.

For the MBS session transmitted to a designated RRC _ CONNECTED UE, since NACK information of a TB of the MBS session only corresponds to 1 bit or 2 bits, and a length of UCI on PUCCH format 2/3/4 is not less than 3, the NACK information of the TB cannot be directly transmitted to the gNB through PUCCH format 2/3/4, but a bit sequence corresponding to NACK information needs to be defined for PUCCH format 2, PUCCH format 3, and PUCCH format 4 in a 3GPP NR protocol, and the length of the bit sequence is not less than 3, and when the UE decodes a TB of the MBS session in error, the UE transmits the bit sequence through PUCCH format 2/3/4 for feeding back the NACK information of the TB to the gNB.

The bit sequence corresponding to the NACK information defined for PUCCH format 2, PUCCH format 3 and PUCCH format 4 in the 3GPP NR protocol is applicable to any one MBS session where NACK information is fed back through PUCCH format 2/3/4, which is transmitted to a group of designated RRC _ CONNECTED UEs.

In order to ensure the coverage of the PUCCH and improve the reception performance of the gbb on the NACK information fed back by the UE through the PUCCH, in the HARQ-ACK feedback method of the present application, when the UE decodes the TB of the MBS incorrectly, the UE may feed back a bit sequence corresponding to the NACK information of the TB of the MBS to the gbb through PUCCH format 2/3/4. The length of the bit sequence is not less than 3, so that the bit sequence is fed back to the gNB through PUCCH format 2/3/4 after channel coding.

The number of bits contained in the UCI information carried by the PUCCH format 2/3/4 is divided into two cases: number of bits > =12 or 3< = number of bits < =11. The former uses POLAR codes (see 3gpp TS 38.212 section 6.3.1.2.1), and the latter uses small block length coding (see 3gpp TS 38.212.6.3.1.2.2). L1 is used to indicate the length of the bit sequence corresponding to the NACK information, and the value range of L1 is as follows:

(1)L1>＝12

(2) L1> =3 and L1< =11

The following two methods for determining the bit sequence corresponding to NACK information are available:

the method comprises the following steps: it is explicitly given in the 3GPP NR protocol: the bit sequence corresponding to the NACK information is a fixed sequence: the length is fixed and the value of each bit in the sequence is fixed.

The method 2 comprises the following steps: it is explicitly given in the 3GPP NR protocol: and generating a bit sequence corresponding to the NACK information.

Aiming at MBS conversation transmitted to a group of appointed RRC _ CONNECTED UE, when a group of PUCCHs are configured for each PTM bearer of the MBS conversation by a gNB, if at least one PUCCH in the group of PUCCHs adopts PUCCH format 2/3/4, the group of sequence generation parameters are configured for the group of PUCCHs by the gNB, the group of parameters are parameters used in a generation formula of a bit sequence corresponding to NACK information, a bit sequence can be uniquely determined by the group of sequence generation parameters and the generation formula of the bit sequence corresponding to the NACK information, and the bit sequence is the bit sequence corresponding to the NACK information.

According to the method 2, for each PTM bearer of the MBS session, when a gNB transmits a TB of the MBS session to UE through the PTM bearer, if the UE decodes the TB on the PTM bearer incorrectly, the UE selects a PUCCH from a group of PUCCHs configured for the PTM bearer, if the selected PUCCH adopts PUCCH format 2/3/4, the UE uniquely determines a bit sequence according to a group of sequence generation parameters contained in configuration information of the group of PUCCH configured for the PTM bearer and a generation formula of the bit sequence corresponding to NACK information, and the UE feeds back the bit sequence to the gNB through the selected PUCCH.

Two examples are given below for the generation formula of the bit sequence corresponding to NACK information.

Example 1: all 0 sequences with the length of L1 or all 1 sequences with the length of L1 are adopted to represent bit sequences corresponding to NACK information, and L1 is a generation parameter of the bit sequences corresponding to the NACK information.

Example 2: and generating a bit sequence corresponding to the NACK information by adopting a pseudo-random sequence generation formula in section 5.2.1 in a 3GPP TS38.211 protocol, wherein when the bit sequence corresponding to the NACK information is generated by adopting the formula, the length of the pseudo-random sequence and the initialization value of the pseudo-random sequence are generation parameters of the bit sequence corresponding to the NACK information.

In order to enable the ue to feed back the NACK information of the TB and also feed back the Channel Quality Indication (CQI) measurement result obtained by its own measurement to the gNB, so that the gNB may use a suitable MCS value in the retransmission of the TB of the MBS session and/or the initial transmission of the subsequent TB, optionally, when configuring a set of PUCCHs for each PTM bearer, each PUCCH is assigned a CQI range, and the CQI ranges corresponding to different PUCCHs do not overlap.

Specifically, the gNB may pre-specify a CQI range corresponding to each pre-configured PUCCH, and CQI ranges corresponding to different PUCCHs do not overlap. When the UE has an error in decoding the TB of the MBS, the UE selects one PUCCH from a group of pre-configured PUCCHs according to the self CQI measurement result, and the self CQI measurement result of the UE is contained in a CQI range corresponding to the PUCCH. And the UE transmits the NACK information (corresponding to PUCCH format 0/1) or the bit sequence (corresponding to PUCCH format 2/3/4) corresponding to the NACK information to the gNB through the selected PUCCH.

After the gNB sends the TBs, each pre-configured PUCCH is detected, when one PUCCH is detected, the gNB not only determines that the current TB is not correctly received by any UE, but also determines the CQI range of the UE which cannot correctly receive the current TB, and the gNB summarizes the detection results of the pre-configured PUCCHs and executes retransmission scheduling of the corresponding TB and/or initial transmission scheduling of subsequent TBs.

The gNB may configure a CQI range for each pre-configured PUCCH using one of the following methods:

the method comprises the following steps: each PUCCH is configured with an MCS index range, and the MCS index ranges corresponding to different PUCCHs do not overlap.

When the UE has an error in decoding the TB of the MBS, the UE determines an MCS subscript adopted when the gNB is expected to transmit the current TB of the MBS according to the measurement of the UE, selects one PUCCH from a PUCCH set according to the expected MCS subscript value, and feeds back NACK information to the gNB through the selected PUCCH, so that the UE feeds back the expected MCS subscript to the gNB while feeding back the NACK information.

Specifically, the gNB determines the MCS index range that the PTM bearer can adopt when transmitting the MBS session with the PTM bearer, which should be a subset of the MCS index range that can be adopted in the 3GPP protocol. The MCS index range is divided into a plurality of sub-ranges, each sub-range corresponding to one PUCCH. There is no overlap between the sub-ranges.

The method 2 comprises the following steps: each PUCCH corresponds to a dynamic MCS index range, and the dynamic MCS index ranges corresponding to different PUCCHs are not overlapped.

Specifically, the MCS index adopted by the gNB when transmitting the current TB is denoted by Imcs, Q denotes the number of PUCCHs in a pre-configured set of PUCCHs, and the MCS index range [0, imcs-1] is divided into Q sub-ranges, where each sub-range includes, on average, a = int (Imcs/Q) MCS index values, and int (x) denotes the operation of rounding x. The MCS subscript range corresponding to the qth sub-range in the first Q-1 sub-range is: [ (Q-1) × a, Q × a), Q =1, …, Q-1, the Q-th sub-range corresponds to MCS index range: [ (Q-1) A, imcs-1]. The Q PUCCHs respectively correspond to the Q sub-ranges.

Such as: imcs =6, the number of PUCCHs in the PUCCH set Q =3, and each sub-range includes Imcs/Q =2 MCS index values:

the MCS index range corresponding to the first PUCCH is: MCS index 0 and MCS index 1;

the MCS index range corresponding to the second PUCCH is: MCS index 2 and MCS index 3;

the MCS index range corresponding to the third PUCCH is: MCS index 4 and MCS index 5.

For another example: if the current TB adopts Imcs =3, the number of PUCCHs in the PUCCH set Q =3, and each sub-range includes Imcs/Q =1 MCS index value:

the MCS index range corresponding to the first PUCCH is: MCS index 0;

the MCS index range corresponding to the second PUCCH is: MCS index 1;

the MCS index range corresponding to the third PUCCH is: MCS index 2.

The method 3 comprises the following steps: each PUCCH in the set is assigned with a CQI subscript range, and the corresponding CQI subscript ranges of different PUCCHs are not overlapped.

When the UE has an error in decoding the TB of the MBS, the UE selects one PUCCH from the PUCCH set according to the CQI value measured by the UE, the CQI subscript corresponding to the CQI value of the UE is included in the range of the CQI subscript corresponding to the selected PUCCH, and the NACK information is fed back to the gNB through the selected PUCCH, so that the NACK information is fed back and the CQI measurement result of the UE is fed back to the gNB at the same time.

The parameter used to represent the CQI measurement result of the UE may be an MCS value, or other parameters may be used to represent the CQI measurement result of the UE. When the CQI measurement result is expressed by an MCS value, the above method 3 is changed to the above method 1 or the above method 2. The above method 3 does not specify a specific parameter indicating the CQI measurement result, and thus has a wider application range. Since the parameter indicating the CQI measurement result of the UE is not the content of the present application, and is only the existing feasible parameter indicating the CQI measurement result, the present application is not described in detail again.

The above methods 1 and 2 are preferably: the method 1 is simple, the method 2 is more flexible, and the feedback information is more accurate.

In summary, the configuration information of each PUCCH in the resource configuration information of the MBS session includes the following contents:

(1) The number of PUCCHs;

(2) The format adopted by each PUCCH;

(3) Optionally, a CQI range corresponding to each PUCCH.

When a CQI range is appointed for each PUCCH, the UE feeds back NACK information and simultaneously feeds back a CQI measurement result to the gNB, so that the gNB performs retransmission scheduling of the TB of the MBS session and initial transmission scheduling of the subsequent TB; if a CQI range is not specified for each PUCCH, the UE may randomly select one PUCCH when feeding NACK information back, and feed the NACK information back to the gNB through the selected PUCCH. (4) Optionally, the NACK information corresponds to a generation parameter of a bit sequence.

When a bit sequence corresponding to the NACK information is generated by a generating formula and at least one PUCCH adopts PUCCH format 2/3/4, the PUCCH configuration information needs to carry: and generating parameters of the bit sequence corresponding to the NACK information.

And the gNB and the UE uniquely determine a bit sequence according to the generation formula of the bit sequence corresponding to the group of parameters and the NACK information, wherein the bit sequence is the bit sequence corresponding to the NACK information.

202, gNB sends resource configuration information of MBS conversation to user equipment, the resource configuration information includes configuration information of each PTM bearing configured for MBS conversation and configuration information of a group of PUCCHs configured for each PTM bearing.

The configuration information of each PTM bearer is used for the UE receiving the MBS conversation to establish the corresponding PTM bearer and receive the data on the corresponding RB of the MBS conversation through the established PTM bearer. For any PTM bearer, when the UE decodes the TB on the PTM bearer in error, the UE generates NACK information of the TB, configuration information of a group of PUCCHs configured for the PTM bearer is used for the UE to determine a group of PUCCHs, and one PUCCH is selected from the group of PUCCHs to feed back the NACK information of the TB to the gNB.

For a PTM bearer, configuration information of a set of PUCCHs configured for the PTM bearer includes:

(1) The number of PUCCHs;

(2) The format of each PUCCH;

(3) Optionally, a CQI range corresponding to each PUCCH;

(4) Optionally, the NACK information corresponds to a generation parameter of a bit sequence.

More specifically, the configuration information of one MBS session includes the following:

when the MBS session comprises at least one non-SPS RB, (1) a G-RNTI configured for the MBS session; (2) Transmitting configuration information of PTM bearer of non-SPS RB of the MBS session; (3) Configuration information of a set of PUCCHs configured for the PTM bearer.

When the MBS session contains at least one SPS RB, (1) a G-CS-RNTI configured for the MBS session; (2) For each SPS RB, transmitting configuration information of a PTM bearer of the SPS RB; (3) Configuration information of a set of PUCCHs configured to the PTM bearer of each transmission SPS RB.

Optionally, for SPS RBs with the same periodicity, the configuration information of the PTM bearer configured for the SPS RBs in a unified manner, and the configuration information of a group of PUCCHs configured for the PTM bearer configured in a unified manner.

The configuration information of a set of PUCCHs configured for each PTM bearer includes:

(1) The number of PUCCHs; (2) the format used by each PUCCH; (3) a CQI range corresponding to each PUCCH; (4) And when at least one PUCCH adopts PUCCH format 2/3/4 and the bit sequence corresponding to the NACK information is generated by adopting a generation formula, generating parameters of the bit sequence corresponding to the NACK information.

And the gNB transmits all the non-SPS RBs of the MBS session through a PTM bearer, and the PTM bearer adopts a dynamic scheduling mode. For each SPS RB of the MBS conversation, the gNB transmits the RB through a PTM bearer, and the PTM bearer adopts a semi-static scheduling mode. For SPS RBs with the same periodicity, optionally, the gNB transmits data on the SPS RBs through a PTM bearer configured for the SPS RBs in a unified manner, where the PTM bearer configured in a unified manner adopts a semi-persistent scheduling manner. In order to enable the UE to receive the MBS session, the gNB sends the configuration information of each PTM bearer used by the MBS session to the UE, so that the UE establishes each PTM bearer according to the configuration information of each PTM bearer used by the MBS session and is used for receiving the MBS session.

And the gNB expects the UE to receive the MBS session through the configured PTM bearer and simultaneously feeds back NACK information of the TB of the MBS session transmitted on the PTM bearer to the gNB through a group of PUCCHs configured for the PTM bearer. Furthermore, the gNB also expects the UE to feed back the CQI measurement result of the UE to the gNB while feeding back NACK information, so that the gNB can perform scheduling for retransmission and scheduling for initial transmission. Therefore, for each PTM bearer of an MBS session, the gNB needs to send configuration information of a set of PUCCHs configured for the PTM bearer to the UE. The PUCCH configuration information comprises a format adopted by each PUCCH and a corresponding CQI range, so that the UE selects a proper PUCCH according to a self CQI measurement result and feeds back NACK information of a TB on a PTM bearer generated by the UE to the gNB. When the PUCCH selected by the UE adopts the PUCCH format 2/3/4, the UE does not directly feed back the NACK information of the TB to the gNB through the selected PUCCH, but feeds back a bit sequence corresponding to the NACK information of the TB to the gNB through the selected PUCCH.

For other configuration information of the MBS session, the information has no influence on the description of the method in the present application and is not described again.

203, the user equipment receives the resource configuration information of the MBS conversation sent by the gNB, stores the received resource configuration information of the MBS conversation, and establishes a corresponding PTM bearing according to the configuration information of each point-to-multipoint PTM bearing in the resource configuration information of the MBS conversation for receiving the MBS conversation.

Specifically, for each RRC _ CONNECTED UE receiving the MBS session, the UE receives and stores the configuration information of the MBS session sent by the gNB. And the UE establishes each PTM bearer according to the configuration information of each PTM bearer in the configuration information of the MBS conversation and is used for receiving the transmission block of the MBS conversation transmitted by the gNB through each PTM bearer.

204, the gNB generates each transport block TB of the MBS session and sends the transport block TB to the user equipment through a corresponding PTM bearer.

Specifically, the gNB transmits TBs assembled from data on the non-SPS RBs through a PTM bearer configured for the non-SPS RBs; the gNB transmits a TB assembled by data on an SPS RB through a PTM bearer configured for the RB; optionally, for SPS RBs with the same periodicity, the gNB transmits TBs assembled from data on these RBs over a PTM bearer that is uniformly configured for these RBs.

205, the ue receives each transport block of the MBS session from the gNB via the established PTM bearers.

Specifically, for each RRC _ CONNECTED UE receiving the MBS session, the UE receives a TB assembled from data on non-SPS RBs over a PTM bearer established for the non-SPS RBs; the UE receives TB assembled by data on an SPS RB through a PTM bearer established for the RB; optionally, for SPS RBs with the same periodicity, the UE receives TBs assembled from data on these RBs through a PTM bearer established uniformly for these RBs.

206, for each transport block of the MBS session, when the ue determines that the decoding of the transport block is erroneous, generating NACK information of the transport block, and feeding back the generated NACK information of the transport block to the gNB through the PUCCH, where the NACK information of the transport block is used for the gNB to retransmit the transport block.

Specifically, the UE receives each transmission block of an MBS conversation sent by a gNB through each PTM bearer, when the UE decodes a TB on one PTM bearer wrongly, the UE generates NACK information of the transmission block, the UE selects one PUCCH from a group of PUCCHs configured for the PTM bearer according to the self CQI measurement result, the self CQI measurement result of the UE is contained in a CQI range corresponding to the selected PUCCH, when the selected PUCCH adopts PUCCH format 0/1, the UE feeds back the NACK information to the gNB through the selected PUCCH, and when the selected PUCCH adopts PUCCH format 2/3/4, the UE feeds back a bit sequence corresponding to the NACK information to the gNB through the selected PUCCH.

When a bit sequence corresponding to the NACK information is defined as one fixed sequence in the 3GPP protocol, the UE feeds back the defined fixed sequence to the gNB through the selected PUCCH

When a generation formula of a bit sequence corresponding to NACK information is defined in a 3GPP protocol, the UE generates a bit sequence according to the generation formula of the bit sequence corresponding to NACK information and a "generation parameter of the bit sequence corresponding to NACK information" included in configuration information of a group of PUCCHs configured for the PTM bearer, and the UE feeds back the generated bit sequence to the gNB through the selected PUCCH.

Through the processing, when the UE decodes one transmission block of the MBS session incorrectly, the UE feeds back NACK information of the transmission block to the gNB through the selected PUCCH, and feeds back a CQI measurement result of the UE to the gNB.

207, for each transport block of the MBS session, after the gNB sends the transport block to the ue through the corresponding PTM bearer, the gNB detects each PUCCH in a set of PUCCHs configured for the PTM bearer, and performs retransmission scheduling of the transport block and/or initial transmission scheduling of subsequent TBs according to the detection result.

Specifically, after the gNB generates a transport block TB of the MBS session and sends the TB to user equipment through a corresponding PTM bearer, the gNB detects each PUCCH in a group of PUCCHs configured to the PTM bearer, for each detected PUCCH, the gNB determines the channel quality condition of the UE feeding back the PUCCH according to the CQI range corresponding to the PUCCH, summarizes the detected CQI ranges corresponding to the PUCCHs, and performs retransmission scheduling on the TB and initial transmission scheduling on the subsequent TB. When the gNB does not detect any PUCCH, the gNB performs initial transmission scheduling on the subsequent TB.

Based on the technical scheme, the base station sends the resource configuration information of the MBS conversation to the user equipment, and the resource configuration information of the MBS conversation comprises the following steps: the user equipment establishes each PTM bearer according to the configuration information of each PTM bearer in the resource configuration information of the MBS session to receive each TB of the MBS session sent by the base station, if the user equipment receives the TB sent by the base station through the PTM bearer through the first PTM bearer, the user equipment generates NACK information of the first TB, the NACK information of the first TB is fed back to the base station through the first PUCCH in a group of PUCCHs configured for the first PTM bearer by the base station, and the base station can retransmit the NACK information of the first TB according to the detected NACK information of the first TB. When each PUCCH in a group of PUCCHs configured for the first PTM bearer by the base station has a corresponding CQI range, the UE selects the first PUCCH according to the CQI measurement result of the UE, and the CQI measurement result of the UE is contained in the CQI range corresponding to the first PUCCH. The method can improve the reliability of MBS session transmission, thereby ensuring that the receiving of the user equipment to the MBS meets the reliability requirement of the MBS.

The above steps are a general description of the method of the present application. Specifically, for the PTM bearer of the non-SPS RBs transmitting the MBS session, a more detailed implementation of the above steps 204-207 is as follows:

step 1: and the gNB determines the beam coverage area where each UE receiving the MBS session is positioned according to the position information of a group of designated RRC _ CONNECTED state UEs receiving the MBS session. When there is at least one RRC _ CONNECTED state UE in a beam coverage area, the gNB records the index of the beam coverage area, the number of recorded beam coverage areas is denoted by M (M < = K), the beam used by the mth recorded beam coverage area is denoted by beam b (M), M =1, …, M.

Specifically, K denotes the number of beams used by the gNB when transmitting the SS/PBCH BLOCK in the cell, K denotes the kth beam used by the Synchronization Signal/Physical Broadcast Channel BLOCK (SS/PBCH BLOCK), K =1, …, K. The coverage area of the kth beam is denoted by beam coverage area k.

And the gNB determines the beam coverage area where each UE receiving the MBS session is positioned according to the position information of a group of designated RRC _ CONNECTED state UEs receiving the MBS session. When there is at least one RRC _ CONNECTED state UE within a beam coverage area, the gNB records the index of the beam coverage area.

Step 2: for a PTM bearer of an RB transmitted aperiodically for transmitting the MBS session, when the gNB transmits a TB of the MBS session through the PTM bearer, the gNB allocates resources for a Physical Downlink Control Channel (PDCCH), a Physical Downlink Shared Channel (PDSCH) and a PUCCH, respectively. The gNB allocates M × R1 consecutive slots to the PDCCH and allocates resources to the PDCCH in each slot. The gNB allocates M × R1 consecutive slots to the PDSCH and allocates resources to the PDSCH in each slot. R1 is the number of times the TB is repeatedly transmitted on the PDSCH, R1> =1. The gNB allocates M × R2 consecutive slots to the PUCCH, where R2 is the number of times the PUCCH is repeatedly transmitted, and R2> =1.

M × R1 consecutive PDCCH slots and M × R1 consecutive PDSCH slots correspond one-to-one: the PDCCH transmitted in each PDCCH time slot has an associated PDSCH, and the PDCCH and the associated PDSCH satisfy a timing relationship: the PDCCH is transmitted in a time slot T, the associated PDSCH is transmitted in a time slot T + DELAY, the DELAY is the timing difference between the PDCCH and the associated PDSCH, the value of the DELAY is given by a DCI format on the PDCCH, and the DCI format on the PDCCH is scheduling information of the associated PDSCH.

The PDSCH sent in the first PDSCH slot of the last M PDSCH slots and the PUCCH sent in the first PUCCH slot of the M × R2 PUCCH slots satisfy a timing relationship: when PDSCH is transmitted in slot T1, PUCCH is transmitted in slot T1+ DELAY1, and DELAY1 is the timing difference between PDSCH and PUCCH. The value of DELAY1 is given by the DCI format on the PDCCH associated with the PDSCH.

And step 3: the gNB divides M × R1 consecutive PDCCH/PDSCH slots into R1 groups, each group consisting of M consecutive slots. In each group of time slots, the gNB respectively transmits the PDCCH/PDSCH by using the recorded M beams: and transmitting the PDCCH/PDSCH by using a beam b (m) in the mth time slot. The gNB transmits the PDCCH/PDSCH once in different beam coverage areas through each group of time slots, and transmits the PDCCH/PDSCH R1 times in each beam coverage area through R1 group of time slots. And the CRC of the PDCCH is scrambled by G-RNTI, and the PDSCH adopts the G-RNTI when bits are scrambled.

And 4, step 4: and for the UE receiving the MBS, the UE selects a proper PDCCH/PDSCH time slot to receive the PDCCH/PDSCH in each group of PDCCH/PDSCH time slots according to the beam coverage area in which the UE is positioned.

Such as: and if the UE is located in the beam coverage area b (m), the UE can receive the PDCCH/PDSCH in the mth time slot in each group of PDCCH/PDSCH time slots, and the UE can perform merging decoding on the R1 PDSCHs received in the R1 group of time slots so as to improve the receiving performance of the TB on the PDSCH.

And 5: when the UE decodes TB on the PDSCH wrongly, the UE generates NACK information, the UE selects one PUCCH from a PUCCH set according to the CQI measurement result of the UE, when the selected PUCCH adopts a PUCCH format of 0/1, the UE feeds the NACK information back to the gNB through the selected PUCCH, and when the selected PUCCH adopts a PUCCH format of 2/3/4, the UE feeds a bit sequence corresponding to the NACK information generated by the UE back to the gNB through the selected PUCCH. And when the bit sequence corresponding to the NACK information is generated by a generation formula, the UE generates the bit sequence corresponding to the NACK information according to a group of parameters which are contained in the configuration information of a group of PUCCHs configured for the PTM bearer and used for determining the bit sequence corresponding to the NACK information.

Step 6: the UE can determine the starting positions of M R2 continuous PUCCH time slots according to the received PDCCH and PDSCH, the UE divides the M R2 continuous PUCCH time slots into R2 groups, each group comprises M continuous PUCCH time slots, when the UE determines that the UE is located in a beam coverage area b (M), the UE sends the selected PUCCH in the mth PUCCH time slot in each group of PUCCH time slots, the selected PUCCH carries NACK information generated by the UE or carries a bit sequence corresponding to the NACK information generated by the UE, and the bit sequence corresponding to the NACK information or the NACK information is repeatedly sent for R2 times through the PUCCH selected by the UE in the mth PUCCH time slot in each group of PUCCH time slots.

And 7: after sending the PDCCH and the PDSCH, the gNB divides M × R2 continuous PUCCH time slots into R2 groups, each group comprises M continuous PUCCH time slots, the UE located in a beam coverage area b (M) feeds back NACK information generated by the UE or feeds back a bit sequence corresponding to the NACK information generated by the UE through the mth PUCCH time slot in each group of PUCCH time slots, and the NACK information or the bit sequence corresponding to the NACK information is repeatedly sent for R2 times through the mth PUCCH time slot in the R2 group PUCCH time slots.

And step 8: the gNB detects each PUCCH in the PUCCH set within each PUCCH slot. How the gNB detects the PUCCH is not the content of the present invention, and is not described in detail.

And step 9: when detecting a qth PUCCH in a PUCCH set in a beam coverage area b (m), a gNB determines the channel quality condition of the UE feeding back the PUCCH according to a CQI range corresponding to the PUCCH, summarizes each PUCCH detected in the beam coverage area, determines the overall condition of the channel quality of the UE which fails to correctly decode the TB in the beam coverage area b (m), and performs retransmission scheduling and initial transmission scheduling according to the summarized UE channel quality condition when retransmitting the current TB or an initial transmission subsequent TB in the beam coverage area b (m).

Specifically, for the PTM bearer of one SPS RB transmitting the MBS session, another more detailed implementation of steps 204-207 above is as follows:

Step 2: and the gNB configures semi-static PDSCH resources and semi-static PUCCH resources for the PTM bearer, the semi-static PDSCH resources are used for periodically sending TBs consisting of data on corresponding RBs, and when UE (user equipment) decodes the TBs on the PDSCH incorrectly, the semi-static PUCCH resources are used for feeding back NACK (negative acknowledgement) information of the corresponding TBs.

And when the corresponding RB periodically sends the TBs with equal length by taking P wireless frames as a period, the period of the semi-static PDSCH resource configured by the gNB for the PTM bearer is P wireless frames.

And the PTM bearer comprises M R11 continuous time slots in each period, and the PDSCH is sent by adopting the same PDSCH resource in each time slot, and the PDSCH bears the same TB consisting of data on corresponding RB. R11 is the number of times the TB is repeatedly transmitted on the PDSCH, and R11> =1.

And the period of the semi-static PUCCH resource configured by the gNB for the PTM bearer is P radio frames. The semi-static PUCCH resource includes M × R12 consecutive slots, and R12 is the number of times that NACK information or a bit sequence corresponding to NACK information on the PUCCH is repeatedly transmitted.

The PDSCH transmitted in the first PDSCH slot of the last M PDSCH slots and the PUCCH transmitted in the first PUCCH slot of the M × R12 PUCCH slots satisfy a timing relationship: when PDSCH is transmitted in slot T11, PUCCH is transmitted in slot T11+ DELAY11, and DELAY11 is the timing difference between PDSCH and PUCCH. And the value of the DELAY11 is determined by the gNB and is configured to the UE as the configuration information of the PTM bearer.

And step 3: the gNB divides M × R11 consecutive PDSCH slots into R11 groups, each group consisting of M consecutive slots. In each group of time slots, the gNB transmits PDSCH using the recorded M beams, respectively: the PDSCH is transmitted using beam b (m) in the mth slot. The gNB transmits the PDSCH in different beam coverage areas once per group of slots and R11 times per beam coverage area over R11 groups of slots. Each PDSCH employs G-CS-RNTI when bits are scrambled.

And 4, step 4: and for the UE receiving the MBS, the UE selects a proper PDSCH time slot to receive the PDSCH from M R11 continuous time slots corresponding to the semi-static PDSCH resources in each period according to the beam coverage area in which the UE is positioned.

And 5: when the UE decodes the TB on the PDSCH wrongly, the UE generates NACK information, one PUCCH is selected from a PUCCH set according to the CQI measurement result of the UE, and the NACK information generated by the UE is borne on the PUCCH or a bit sequence corresponding to the NACK information generated by the UE is borne.

Step 6: the method comprises the steps that the UE divides M × R12 continuous PUCCH time slots into R12 groups, each group comprises M continuous PUCCH time slots, when the UE determines that the UE is located in a beam coverage area b (M), the UE sends a selected PUCCH in the mth PUCCH time slot in each group of PUCCH time slots, the selected PUCCH carries NACK information generated by the UE or carries a bit sequence corresponding to the NACK information generated by the UE, and the bit sequence corresponding to the NACK information or the NACK information is repeatedly sent for R12 times through the PUCCH selected by the UE in the mth PUCCH time slot in each group of PUCCH time slots.

And 7: after transmitting PDSCH, the gNB divides M × R12 consecutive PUCCH slots into R12 groups, each group including M consecutive PUCCH slots: and the UE positioned in the beam coverage area b (m) feeds back the NACK information generated by the UE or feeds back the bit sequence corresponding to the NACK information generated by the UE through the mth PUCCH slot in each group of PUCCH slots, and the bit sequence corresponding to the NACK information or the NACK information is repeatedly transmitted for R12 times through the mth PUCCH slot in the R12 groups of PUCCH slots.

And 8: the gNB detects each PUCCH in the PUCCH set within each PUCCH slot.

The present application further provides a base station, where the base station uses the HARQ-ACK feedback method provided by the present application, and specifically, the base station includes the following functions:

the base station allocates wireless resources to the MBS conversation and generates resource allocation information of the MBS conversation, wherein the resource allocation information of the MBS conversation comprises: configuration information of each point-to-multipoint PTM bearer of the MBS session and configuration information of a group of physical uplink control channels PUCCH configured by each PTM bearer;

the base station sends resource configuration information of the MBS conversation to user equipment;

The application also provides a user equipment, which adopts the HARQ-ACK feedback method provided by the application, and the user equipment comprises the following functions:

Fig. 3 is a schematic block diagram of a communication system according to an embodiment of the present application, where the communication system 300 includes:

a base station 310, configured to configure radio resources for a multicast broadcast service MBS session, and generate resource configuration information of the MBS session, where the resource configuration information of the MBS session includes: configuration information of each point-to-multipoint PTM bearer of the MBS session and configuration information of a group of physical uplink control channels PUCCH of each PTM bearer;

the base station 310 is further configured to send resource configuration information of the MBS session to a user equipment;

the user equipment 320 is configured to receive the resource configuration information of the MBS session sent by the base station, store the resource configuration information of the MBS session, and establish a corresponding PTM bearer according to the configuration information of each PTM bearer in the resource configuration information of the MBS session, so as to receive the MBS session through the established PTM bearer;

the base station 310 is further configured to generate a first transport block TB of the MBS session, send the first TB to the user equipment through a first PTM bearer in the PTM bearer, where the first TB is assembled from data on an RB transmitted through the first PTM bearer in a radio bearer RB of the MBS session;

the user equipment 320 is further configured to receive each TB of the MBS session from the base station through the established PTM bearer, where each TB of the MBS session includes the first TB;

the ue 320 is further configured to determine that the received first TB is decoded in error, generate non-acknowledgement NACK information of the first TB, and feed back, by the ue, the NACK information of the first TB to the base station through a first PUCCH in a set of PUCCHs carried by the first PTM, where the NACK information of the first TB is used for the base station to retransmit the first TB;

the base station 310 is further configured to detect each PUCCH in a group of PUCCHs configured for the first PTM bearer, and perform retransmission scheduling of the first TB and/or perform initial transmission scheduling on a subsequent TB according to a detection result.

Optionally, the configuration information of a group of PUCCHs carried by the PTM includes:

a number of PUCCHs in the set of PUCCHs;

a format of each PUCCH in the set of PUCCHs, wherein the format of each PUCCH in the set of PUCCHs is any one of the following formats: PUCCH format 0, PUCCH format 1, PUCCH format 2, PUCCH format 3, and PUCCH format 4.

Optionally, the CQI range corresponding to each PUCCH in the group of PUCCHs is determined according to any one of the following methods:

configuring a modulation and coding method MCS index range for each PUCCH in the group of PUCCHs, wherein the MCS index ranges corresponding to different PUCCHs are not overlapped; or the like, or, alternatively,

each PUCCH in the group of PUCCHs corresponds to a dynamic MCS index range, and the dynamic MCS index ranges corresponding to different PUCCHs are not overlapped; or the like, or, alternatively,

and each PUCCH in the group of PUCCHs is assigned with a CQI subscript range, and the corresponding CQI subscript ranges of different PUCCHs do not overlap.

Optionally, the bit sequence corresponding to the NACK information is defined as a sequence with a fixed length in a 3GPP NR protocol, and a value of each bit in the bit sequence corresponding to the NACK information is fixed.

Optionally, the generating formula includes any one of:

the bit sequence corresponding to the NACK information is as follows: a full 0 sequence with a length of L1, wherein L1 is a generation parameter of a bit sequence corresponding to the NACK information; or the like, or, alternatively,

the bit sequence corresponding to the NACK information is as follows: a full 1 sequence with a length of L1, wherein L1 is a generation parameter of a bit sequence corresponding to the NACK information; or the like, or, alternatively,

the bit sequence corresponding to the NACK information is generated by a pseudorandom sequence generation formula, which includes two parameters: and the length of the pseudo-random sequence and the initialization value of the pseudo-random sequence are generation parameters of a bit sequence corresponding to the NACK information.

Optionally, if at least one PUCCH in a group of PUCCHs carried by the PTM adopts PUCCH format 2/3/4 and a bit sequence corresponding to the NACK information in the 3GPP NR protocol is generated by a generating formula, the configuration information of the group of PUCCHs carried by the PTM further includes: and generating parameters of a bit sequence corresponding to the NACK information.

Optionally, the user equipment 320 is further configured to determine the first PUCCH from a group of PUCCHs carried by the first PTM, and a measurement result of the CQI of the user equipment is included in a CQI range corresponding to the first PUCCH.

Optionally, when the first PUCCH adopts PUCCH format 0/1, the user equipment 320 is specifically configured to: and feeding back the NACK information of the first TB to the base station through the first PUCCH.

Optionally, when the first PUCCH adopts PUCCH format 2/3/4, the user equipment 320 is specifically configured to: feeding back a bit sequence corresponding to the NACK information of the first TB to the base station through the first PUCCH, wherein the bit sequence corresponding to the NACK information of the first TB is a sequence with a fixed length.

Optionally, when the first PUCCH adopts PUCCH format 2/3/4, the user equipment 320 is specifically configured to: generating a first bit sequence according to a generation formula of a bit sequence corresponding to the NACK information and a generation parameter of the bit sequence corresponding to the NACK information; and feeding back the first bit sequence to the base station through the first PUCCH.

Optionally, the base station is specifically configured to:

when at least one PUCCH is detected, determining the channel quality condition of user equipment feeding back the PUCCH according to the CQI range corresponding to each detected PUCCH, summarizing the CQI ranges corresponding to the detected PUCCHs, and performing retransmission scheduling on the first TB and initial transmission scheduling on subsequent TBs;

and when any PUCCH is not detected, performing initial transmission scheduling on the subsequent TB.

Fig. 4 is a schematic structural diagram of a communication device according to an embodiment of the present application, where the communication device 400 may be a base station described in the foregoing embodiment, and the communication device 400 includes: a memory 410 and at least one processor 420;

a memory 410 for storing computer-executable instructions;

a processor 420 for executing the computer-executable instructions stored by the memory, so that the communication device executes the HARQ-ACK feedback method in the above embodiments. For a specific implementation principle, reference may be made to the above embodiments, which are not described herein again.

The communication device may also include an input/output interface 430.

The input/output interface 430 may include separate output and input interfaces or may be an integrated interface that integrates input and output. The output interface is used for outputting data, and the input interface is used for acquiring input data.

Fig. 5 is a schematic structural diagram of another communication device 500 provided in an embodiment of the present application, where the communication device 500 may be a user equipment described in the foregoing embodiment, and the communication device 500 includes: a memory 510 and at least one processor 520;

a memory 510 for storing computer-executable instructions;

a processor 520 configured to execute the computer-executable instructions stored by the memory, so that the communication device performs the HARQ-ACK feedback method in the above embodiments. For a specific implementation principle, reference may be made to the above embodiments, which are not described herein again.

The communication device may also include an input/output interface 530.

Input/output interface 530 may include separate output and input interfaces or may be an integrated interface that integrates both inputs and outputs. The output interface is used for outputting data, and the input interface is used for acquiring input data.

The embodiment also provides a readable storage medium, and the readable storage medium stores executable instructions, and when the executable instructions are executed by a processor, the HARQ-ACK feedback method in the above embodiments is implemented.

The present embodiment also provides a computer program product comprising a computer program which, when executed by a processor, implements the HARQ-ACK feedback method in the above embodiments.

In the several embodiments provided in the present application, it should be understood that the disclosed apparatus and method may be implemented in other ways. For example, the above-described embodiments of the apparatus are merely illustrative, and for example, the division of the modules is merely a division of logic functions, and other divisions may be realized in practice, for example, a plurality of modules or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed coupling or direct coupling or communication connection between each other may be through some interfaces, indirect coupling or communication connection between devices or modules, and may be in an electrical, mechanical or other form.

The modules described as separate parts may or may not be physically separate, and parts displayed as modules may or may not be physical modules, may be located in one place, or may be distributed on a plurality of network modules. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment.

In addition, functional modules in the embodiments of the present application may be integrated into one processing module, or each of the modules may exist alone physically, or two or more modules are integrated into one module. The integrated module can be realized in a hardware form, and can also be realized in a form of hardware and a software functional module.

The integrated module implemented in the form of a software functional module may be stored in a computer-readable storage medium. The software functional module is stored in a storage medium and includes several instructions for enabling a computer device (which may be a personal computer, a server, or a network device) or a processor (in english: processor) to execute some steps of the methods described in the embodiments of the present application. And the aforementioned storage medium includes: a U-disk, a portable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk, and other media capable of storing program codes.

Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the invention following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the invention pertains. It is intended that the specification and examples be considered as exemplary only, with a true scope and spirit of the application being indicated by the following claims.

It will be understood that the present application is not limited to the precise arrangements described above and shown in the drawings and that various modifications and changes may be made without departing from the scope thereof. The scope of the application is limited only by the appended claims.

Claims

1. A HARQ-ACK feedback method is characterized in that the method is applied to multicast broadcast service MBS conversation and comprises the following steps:

the base station allocates wireless resources to the MBS conversation and generates resource allocation information of the MBS conversation, wherein the resource allocation information of the MBS conversation comprises: the configuration information of a group of physical uplink control channels PUCCH of each PTM bearing;

the user equipment determines that the received first TB is decoded incorrectly, the user equipment generates non-acknowledgement (NACK) information of the first TB, and feeds back the NACK information of the first TB to the base station through a first PUCCH in a group of PUCCHs carried by the first PTM, wherein the NACK information of the first TB is used for retransmitting the first TB by the base station;

2. The method according to claim 1, wherein the configuration information of a group of PUCCHs carried by the PTM comprises:

a number of PUCCHs in the set of PUCCHs;

a format of each PUCCH in the set of PUCCHs, wherein the format of each PUCCH in the set of PUCCHs is any one of the following formats: PUCCH format 0.pucch format 1.pucch format 2.pucch format 3 and PUCCH format 4.

3. The method according to claim 1 or 2,

the configuration information of a group of PUCCHs carried by the PTM further comprises: and the channel quality indication CQI range corresponding to each PUCCH in the set of PUCCHs.

4. The method of claim 3, wherein the CQI range corresponding to each PUCCH in the set of PUCCHs is determined according to any one of the following methods:

configuring a modulation and coding method MCS index range for each PUCCH in the group of PUCCHs, wherein the MCS index ranges corresponding to different PUCCHs are not overlapped; or the like, or a combination thereof,

each PUCCH in the group of PUCCHs corresponds to a dynamic MCS subscript range, and the dynamic MCS subscript ranges corresponding to different PUCCHs are not overlapped; or the like, or, alternatively,

and assigning a CQI index range to each PUCCH in the group of PUCCHs, wherein the corresponding CQI index ranges of different PUCCHs do not overlap.

5. The method of claim 1, wherein a bit sequence corresponding to the NACK message is defined as a sequence with a fixed length in a 3GPP NR protocol, and a value of each bit in the bit sequence corresponding to the NACK message is fixed.

6. The method according to claim 1, wherein a generation formula of the bit sequence corresponding to the NACK information is defined in a 3GPP NR protocol, and the bit sequence corresponding to the NACK information is generated by the generation formula, and the generation formula includes a generation parameter of the bit sequence corresponding to the NACK information.

7. The method of claim 6, wherein the generating formula comprises any one of:

8. The method according to claim 2 or 6, wherein if at least one PUCCH in a set of PUCCHs in the PTM bearer adopts PUCCH format 2/3/4, the configuration information of the set of PUCCHs in the PTM bearer further comprises: and generating parameters of a bit sequence corresponding to the NACK information.

9. The method of claim 3, wherein before the UE feeds back NACK information for the first TB to the base station via a first PUCCH of a group of PUCCHs of the first PTM bearer, the method further comprises:

the user equipment determines the first PUCCH from a group of PUCCHs carried by the first PTM, and the measurement result of the CQI of the user equipment is contained in a CQI range corresponding to the first PUCCH.

10. The method of claim 2, wherein when the first PUCCH adopts PUCCH format 0/1, the UE feeds back NACK information of the first TB to the base station through the first PUCCH, and wherein the method comprises the following steps:

and the user equipment feeds back the NACK information of the first TB to the base station through the first PUCCH.

11. The method of claim 2 or 5, wherein when the first PUCCH adopts PUCCH format 2/3/4, the user equipment feeds back NACK information of the first TB to the base station through the first PUCCH, and the method comprises the following steps:

and the user equipment feeds back a bit sequence corresponding to the NACK information of the first TB to the base station through the first PUCCH, wherein the bit sequence corresponding to the NACK information of the first TB is a sequence with fixed length.

12. The method of claim 2 or 6, wherein when the first PUCCH adopts PUCCH format 2/3/4, the user equipment feeds back NACK information of the first TB to the base station through the first PUCCH, and the method comprises the following steps:

the user equipment generates a first bit sequence according to a generation formula of a bit sequence corresponding to the NACK information and a generation parameter of the bit sequence corresponding to the NACK information;

and the user equipment feeds back the first bit sequence to the base station through the first PUCCH.

13. The method according to claim 1 or 2, wherein the base station performs retransmission scheduling of the first TB and/or initial transmission scheduling of subsequent TBs according to the detection result, comprising:

when the base station detects at least one PUCCH, the base station determines the channel quality condition of user equipment feeding back the PUCCH according to the CQI range corresponding to the PUCCH for each detected PUCCH, and the base station summarizes the detected CQI ranges corresponding to the PUCCHs and carries out retransmission scheduling on the first TB and initial transmission scheduling on the subsequent TB;

and when the base station does not detect any PUCCH, the base station performs initial transmission scheduling on the subsequent TB.

14. A HARQ-ACK feedback system, the system comprising:

a base station, configured to configure wireless resources for a multicast broadcast service MBS session, and generate resource configuration information of the MBS session, where the resource configuration information of the MBS session includes: the configuration information of a group of physical uplink control channels PUCCH of each PTM bearing;

the base station is further configured to generate a first transport block TB of the MBS session, send the first TB to the user equipment through a first PTM bearer in the PTM bearers, where the first TB is assembled from data on an RB transmitted through the first PTM bearer in a radio bearer RB of the MBS session;