Communication method and device in a wireless communication network

Abstract

A terminal and a base station in a wireless communication network and methods performed by the terminal and the base station are disclosed. According to one embodiment, a method performed by a terminal in a wireless communication network comprises receiving a physical downlink control channel, PDCCH, comprising downlink control information, DCI, for scheduling one or more physical downlink shared channels, PDSCHs; receiving the PDSCHs in accordance with the DCI; and transmitting a hybrid automatic repeat request acknowledgement, HARQ-ACK / NACK, codebook for the PDSCHs.

Description

Technical Field

[0001] This application relates to the field of wireless communication technology, and more specifically, to communication methods and devices in wireless communication networks. Background Technology

[0002] In wireless communication systems, the transmission of the Physical Downlink Shared Channel (PDSCH) and the Physical Uplink Shared Channel (PUSCH) is scheduled via Downlink Control Information (DCI) transmitted through the Physical Downlink Control Channel (PDCCH). A single DCI can schedule a single PDSCH or PUSCH, or multiple PDSCHs or PUSCHs simultaneously. Summary of the Invention

[0003] According to one aspect, a method performed by a terminal in a wireless communication network is provided, comprising: receiving a physical downlink control channel (PDCCH), the PDCCH including downlink control information (DCI) for scheduling one or more physical downlink shared channels (PDSCH); receiving the PDSCH according to the DCI; and sending a hybrid automatic repeat request / acknowledge (HARQ-ACK / NACK) codebook for the PDSCH.

[0004] In an exemplary implementation, the DCI includes a Downlink Allocation Index (DAI), which, in the case of a DCI scheduling multiple PDSCHs, indicates information about the first PDSCH among the multiple PDSCHs, or indicates information about the last PDSCH among the multiple PDSCHs.

[0005] In an exemplary implementation, the DCI includes a downlink allocation index (DAI). In the case where multiple PDSCHs scheduled by a PDCCH belong to one or more PDSCH groups, the DAI includes one or more DAI bit fields, each of which corresponds to the DAI information of a PDSCH group.

[0006] In an exemplary embodiment, before sending the HARQ-ACK / NACK codebook, the method further includes: for multiple PDSCHs that are fed back in a HARQ-ACK / NACK codebook, grouping the multiple PDSCHs according to the DCI format of each PDSCH in the multiple PDSCHs, wherein PDSCHs scheduled by the same DCI format belong to the same PDSCH group; and determining the codebook for each PDSCH group.

[0007] In an exemplary embodiment, the method further includes: for multiple PDSCHs that are fed back in a HARQ-ACK / NACK codebook, grouping the multiple PDSCHs according to the number of PDSCHs scheduled by each DCI that schedules the multiple PDSCHs, wherein PDSCHs scheduled by DCIs whose number of scheduled PDSCHs is greater than a threshold value and PDSCHs scheduled by DCIs whose number of scheduled PDSCHs is equal to or less than the threshold value belong to different PDSCH groups; and determining the codebook for each PDSCH group.

[0008] In an exemplary embodiment, before sending the HARQ-ACK / NACK codebook, the method further includes: grouping the multiple PDSCHs that are fed back in a HARQ-ACK / NACK codebook according to the transmission granularity, wherein PDSCHs with the same transmission granularity belong to the same PDSCH group, PDSCHs with different transmission granularities belong to different PDSCH groups, or PDSCHs with different granularities belong to the same PDSCH group determined according to the transmission granularity of a reference PDSCH; and determining the codebook for each PDSCH group.

[0009] In an exemplary implementation, determining the codebook for each PDSCH group includes: determining the HARQ-ACK / NACK codebook for each PDSCH group based on the DAI of the PDSCHs within each PDSCH group and the number of HARQ-ACK / NACK bits corresponding to each PDSCH within each PDSCH group.

[0010] In an exemplary implementation, the DCI includes a downlink allocation index DAI for PDCCH counting, when the number of HARQ-ACK / NACK bits per PDSCH is N. max_p The maximum number of PDSCHs belonging to the same PDSCH group that are scheduled by a PDCCH is N. max_pdsch And when the DAI value in the PDSCH group is M, the number of HARQ-ACK / NACK bits N corresponding to one PDCCH is... t =N max_p×N max_pdsch The total number of bits in the HARQ-ACK / NACK codebook sent is M×N t =M×N max_p ×N max_pdsch .

[0011] In an exemplary implementation, the DCI includes a downlink allocation index (DAI) for PDSCH counting, the DAI indicating information about the last PDSCH among a plurality of PDSCHs scheduled by the DCI, when the number of HARQ-ACK / NACK bits for each PDSCH is N. max_p And when the DAI value in a PDSCH group is M, the total number of bits in the transmitted HARQ-ACK / NACK codebook is M×N. max_p .

[0012] In an exemplary implementation, the DCI includes a downlink allocation index DAI for PDCCH counting, where N is the number of HARQ-ACK / NACK bits corresponding to a PDCCH. t When the DAI value within a PDSCH group is M, the total number of bits in the transmitted HARQ-ACK / NACK codebook is M×N. t , where N t For predefined or semi-static configuration, and N t The sum of HARQ-ACK / NACK bits of each PDSCH scheduled by the PDCCH shall not be less than the sum of the number of HARQ-ACK / NACK bits of each PDSCH. Where Ni is the number of HARQ-ACK / NACK bits of the i-th PDSCH in the PDCCH scheduling.

[0013] In an exemplary implementation, the number of HARQ-ACK / NACK bits for each PDSCH is N. max_p The number of valid HARQ-ACK / NACK bits for each PDSCH is N. r_p The valid HARQ-ACK / NACK values ​​are determined based on the PDSCH decoding results, in N r_p Less than N max_p In the case of HARQ-ACK / NACK, the remaining (N) max_p -N r_p The value of the bit is determined according to a predefined value; and / or the number of HARQ-ACK / NACK bits corresponding to each PDCCH is N. t =N max_p ×N max_pdsch Each PDCCH schedules N PDSCHs. pdsch According to N pdsch The decoding result of each PDSCH determines Nmax_p ×N pdsch The value of the bit HARQ-ACK / NACK, in N max_p ×N pdsch Less than N t In the case of HARQ-ACK / NACK, the remaining N max_p ×(N max_pdsch -N pdsch The value of a bit is determined based on a predefined value.

[0014] In an exemplary embodiment, the DCI includes zero-power channel reference information pilot ZP CSI-RS information, wherein, in the case of scheduling multiple PDSCHs in one DCI, rate matching is performed on the multiple PDSCHs according to the ZP CSI-RS information.

[0015] In an exemplary embodiment, rate matching of the plurality of PDSCHs based on ZP CSI-RS information includes at least one of the following: each of the plurality of PDSCHs is rate matched based on the ZP CSI-RS information; the PDSCHs of each downlink time unit are rate matched based on the ZP CSI-RS information; only the first PDSCH is rate matched based on the ZP CSI-RS information; only the PDSCHs in the first scheduled time unit are rate matched based on the ZP CSI-RS information; and PDSCHs that overlap with the ZP CSI-RS information are rate matched based on the ZP CSI-RS information.

[0016] In an exemplary embodiment, the DCI includes control channel resource set CORESET information, wherein, for a DCI capable of scheduling multiple PDSCHs, the CORESET information includes multiple CORESETs.

[0017] In an exemplary embodiment, the DCI receiving the PDSCH further includes: receiving a demodulation reference signal DMRS of the PDSCH according to the DCI, and receiving the PDSCH according to the DMRS, wherein the DCI indicates a pattern of the DMRS, and the pattern of the DMRS includes one or more of period information, time offset information, time length, and symbol position index.

[0018] In an exemplary embodiment, receiving the PDSCH according to the DCI further includes: receiving the demodulation reference signal DMRS of the PDSCH according to the DCI, and receiving the PDSCH according to the DMRS, wherein the DCI indicates the location information of the DMRS, and the location information of the DMRS is determined by the time domain information of each PDSCH; or, it is jointly determined by the time domain information of all PDSCHs scheduled by the DCI of a PDCCH.

[0019] This application also provides a terminal for performing the above methods.

[0020] According to another aspect, a method is provided performed by a terminal in a wireless communication network, comprising: transmitting a physical downlink control channel (PDCCH), the PDCCH including downlink control information (DCI) for scheduling one or more physical downlink shared channels (PDSCH); transmitting the PDSCH according to the DCI; and receiving a hybrid automatic repeat request response (HARQ-ACK / NACK) codebook for the PDSCH.

[0021] In an exemplary implementation, the DCI includes a Downlink Allocation Index (DAI), which, in the case of a DCI scheduling multiple PDSCHs, indicates information about the first PDSCH among the multiple PDSCHs, or indicates information about the last PDSCH among the multiple PDSCHs.

[0022] In an exemplary implementation, the DCI includes a downlink allocation index (DAI). In the case where multiple PDSCHs scheduled by a PDCCH belong to one or more PDSCH groups, the DAI includes one or more DAI bit fields, each of which corresponds to the DAI information of a PDSCH group.

[0023] In an exemplary implementation, the DCI includes a downlink allocation index DAI for PDCCH counting, when the number of HARQ-ACK / NACK bits per PDSCH is N. max_p The maximum number of PDSCHs belonging to the same PDSCH group that are scheduled by a PDCCH is N. max_pdsch And when the DAI value in the PDSCH group is M, the number of HARQ-ACK / NACK bits N corresponding to one PDCCH is... t =N max_p ×N max_pdsch The total number of bits in the HARQ-ACK / NACK codebook sent is M×N t =M×N max_p ×N max_pdsch .

[0024] In an exemplary implementation, the DCI includes a downlink allocation index (DAI) for PDSCH counting, the DAI indicating information about the last PDSCH among a plurality of PDSCHs scheduled by the DCI, when the number of HARQ-ACK / NACK bits for each PDSCH is N. max_p And when the DAI value in a PDSCH group is M, the total number of bits in the transmitted HARQ-ACK / NACK codebook is M×N. max_p .

[0025] In an exemplary implementation, the DCI includes a downlink allocation index DAI for PDCCH counting, where N is the number of HARQ-ACK / NACK bits corresponding to a PDCCH. t When the DAI value within a PDSCH group is M, the total number of bits in the transmitted HARQ-ACK / NACK codebook is M×N. t , where N t For predefined or semi-static configuration, and N t The sum of HARQ-ACK / NACK bits of each PDSCH scheduled by the PDCCH shall not be less than the sum of the number of HARQ-ACK / NACK bits of each PDSCH. Where Ni is the number of HARQ-ACK / NACK bits of the i-th PDSCH in the PDCCH scheduling.

[0026] In an exemplary implementation, the number of HARQ-ACK / NACK bits for each PDSCH is N. max_p The number of valid HARQ-ACK / NACK bits for each PDSCH is N. r_p The valid HARQ-ACK / NACK values ​​are determined based on the PDSCH decoding results, in N r_p Less than N max_p In the case of HARQ-ACK / NACK, the remaining (N) max_p -N r_p The value of the bit is determined according to a predefined value; and / or the number of HARQ-ACK / NACK bits corresponding to each PDCCH is N. t =N max_p ×N max_pdsch Each PDCCH schedules N PDSCHs. pdsch According to N pdsch The decoding result of each PDSCH determines N max_p ×N pdsch The value of the bit HARQ-ACK / NACK, in N max_p ×N pdsch Less than N t In the case of HARQ-ACK / NACK, the remaining Nmax_p ×(N max_pdsch -N pdsch The value of a bit is determined based on a predefined value.

[0027] In an exemplary embodiment, the DCI includes zero-power channel reference information pilot ZP CSI-RS information, wherein, in the case of scheduling multiple PDSCHs in one DCI, rate matching is performed on the multiple PDSCHs according to the ZP CSI-RS information.

[0028] In an exemplary embodiment, rate matching of the plurality of PDSCHs based on ZP CSI-RS information includes at least one of the following: each of the plurality of PDSCHs is rate matched based on the ZP CSI-RS information; the PDSCHs of each downlink time unit are rate matched based on the ZP CSI-RS information; only the first PDSCH is rate matched based on the ZP CSI-RS information; only the PDSCHs in the first scheduled time unit are rate matched based on the ZP CSI-RS information; and PDSCHs that overlap with the ZP CSI-RS information are rate matched based on the ZP CSI-RS information.

[0029] In an exemplary embodiment, the DCI includes control channel resource set CORESET information, wherein, for a DCI capable of scheduling multiple PDSCHs, the CORESET information includes multiple CORESETs.

[0030] In an exemplary embodiment, transmitting the PDSCH according to the DCI further includes: transmitting a demodulation reference signal DMRS of the PDSCH according to the DCI, and transmitting the PDSCH according to the DMRS, wherein the DCI indicates a pattern of the DMRS, and the pattern of the DMRS includes one or more of period information, time offset information, time length, and symbol position index.

[0031] In an exemplary embodiment, transmitting the PDSCH according to the DCI further includes: transmitting the demodulation reference signal DMRS of the PDSCH according to the DCI, and transmitting the PDSCH according to the DMRS, wherein the DCI indicates the location information of the DMRS, and the location information of the DMRS is determined by the time domain information of each PDSCH; or, it is jointly determined by the time domain information of all PDSCHs scheduled by the DCI of a PDCCH.

[0032] This application also provides a base station for performing the above-described method.

[0033] In addition, this application also provides a computer-readable storage medium storing computer instructions that, when executed by a processor, enable the processor to perform the methods described above performed by a terminal or base station in a wireless communication network. Attached Figure Description

[0034] Figure 1 An example of a signal stream transmitted between a terminal and a base station according to an embodiment of this application is shown.

[0035] Figure 2 An example of the HARQ-ACK / NACK feedback binding window and HARQ-ACK / NACK codebook based on Example 1 is shown.

[0036] Figure 3 An example of the HARQ-ACK / NACK feedback binding window and HARQ-ACK / NACK codebook based on Example 2 is shown.

[0037] Figure 4 An example of the HARQ-ACK / NACK feedback binding window and HARQ-ACK / NACK codebook based on Example 3 is shown.

[0038] Figure 5 An example of a HARQ-ACK / NACK feedback binding window and a HARQ-ACK / NACK codebook based on Example Six is ​​shown.

[0039] Figure 6 An example of the HARQ-ACK / NACK feedback binding window and HARQ-ACK / NACK codebook based on Example 7 is shown.

[0040] Figure 7 A schematic block diagram of a device that can be configured for practicing exemplary embodiments of this application is shown. Detailed Implementation

[0041] The present application will now be described in further detail with reference to the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are merely illustrative of relevant exemplary implementations and are not intended to limit the scope of this disclosure.

[0042] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0043] The terminology used in this disclosure is used to describe particular embodiments and is not intended to limit the scope of other embodiments. Expressions that do not explicitly specify a number generally refer to one or more unless otherwise expressly stated. All terms used herein, including technical and scientific terms, may have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0044] In the following description, a base station is an access device that connects communication equipment to a cellular network and allocates communication resources to the communication equipment. A base station can be any of the following entities: gNB, ng-eNB, eNB, radio access unit, base station controller, base transceiver station, etc. Communication equipment can be any device intended to access services via an access network and capable of being configured for communication through the access network. For example, communication equipment can include, but is not limited to: user terminal (UE), mobile station (MS), cellular phone, smartphone, computer, or multimedia system configured with communication capabilities. It should be noted that in the following description, the terms "communication equipment," "user equipment," "user terminal," "terminal," and "UE" are used interchangeably.

[0045] It should be understood that the embodiments disclosed herein can be applied to various types of cellular networks.

[0046] Figure 1 An example of a signal flow transmitted between terminal 10 and base station 20 according to an embodiment of this application is shown. Those skilled in the art will understand that one or more specific technical details are provided in the following description for illustrative and ease-of-understanding purposes, but embodiments of this application can also be practiced without these features.

[0047] In step 101: Terminal 10 receives PDCCH from base station 20. The received PDCCH may include DCI for scheduling one or more PDSCHs.

[0048] In step 102: Terminal 10 receives PDSCH from base station 20 according to the received DCI.

[0049] In step 103: Terminal 10 sends a HARQ-ACK / NACK codebook for PDSCH to base station 20.

[0050] According to one embodiment, the DCI of the PDCCH may include at least one of the following: information about the coding block group (CBG), information about rate matching, information about the demodulation reference signal (DMRS), information about HARQ-ACK / NACK timing, and information about the downlink assignment index (DAI). Based on the received PDCCH, the terminal 10 can determine at least one of the time-frequency resource information, rate matching information, HARQ-ACK / NACK feedback information, transport block group information, and reference information of the PDSCH scheduled by the PDCCH, and receive the PDSCH from the base station 20 and perform HARQ-ACK / NACK feedback based on the above information.

[0051] The DCI of a PDCCH may include information about the coded block group (CBG). For example, it may include CBG transmission information (CBGTI) and / or CBGflushing out information (CBGFI) indicating whether a coded block may be contaminated. If a DCI can schedule M PDSCHs, then the CBGTI and / or CBGFI of each PDSCH can be independently indicated; or the CBGTI and / or CBGFI of N PDSCHs out of the M PDSCHs can be independently indicated, where N is based on a predefined or signaling configuration. The UE can determine which N PDSCHs out of the M PDSCHs are involved based on the base station's indication, or based on specific values ​​of other bit fields in the DCI, such as whether the new data indicator (NDI) is toggled; or, the M PDSCHs may share a single CBGTI and / or CBGFI bit field.

[0052] The DCI of the PDCCH can include information about rate matching. This rate matching information can be, for example, rate matching information based on resource elements (REs). Alternatively, the rate matching information can be rate matching information based on the control channel resource set (CORESET).

[0053] If the base station is configured with rate matching information based on resource elements (REs) at the granularity, such as zero-power channel state information (ZP CSI-RS), then the PDSCH cannot be mapped to the ZP CSI-RS location indicated in the DCI. If a DCI schedules multiple PDSCHs, then each PDSCH is rate matched according to the same indicated aperiodic ZP CSI-RS information, or the PDSCHs in each downlink time unit are rate matched according to the same indicated aperiodic ZP CSI-RS information, or only the first PDSCH is rate matched according to the indicated aperiodic ZP CSI-RS information, or only the PDSCHs in the first scheduled time unit are rate matched according to the indicated aperiodic ZP CSI-RS information; or rate matching is performed on PDSCHs that overlap with the aperiodic ZP CSI-RS information based on the aperiodic ZP CSI-RS information. The downlink time unit can be one or more time slots, mini-time slots, sub-time slots, or OFDM symbols.

[0054] For example, according to the rule that each PDSCH performs rate matching based on the same aperiodic ZP CSI-RS information, if a DCI schedules 4 PDSCHs, and these 4 PDSCHs occupy symbols 1-3, 4-6, 7-9, and 10-12 respectively in the same downlink time slot, and the DCI indicates that the aperiodic ZP CSI-RS has an offset of 1 symbol relative to the starting symbol of the PDSCH, and the aperiodic ZP CSI-RS occupies 2 consecutive symbols, then the 4 PDSCHs will avoid the resources of the aperiodic ZP CSI-RS in symbols 2-3, 5-6, 8-9, and 11-12 respectively.

[0055] For example, according to the rule that each downlink time unit's PDSCH performs rate matching based on the same aperiodic ZP CSI-RS information, if a DCI schedules 4 PDSCHs, and these 4 PDSCHs occupy symbols 1-7 and 8-14 of the first downlink time slot and symbols 1-7 and 8-14 of the second downlink time slot respectively in two consecutive downlink time slots, and the DCI indicates that the aperiodic ZP CSI-RS occupies symbols 8-9 in one time slot, then only the 2nd and 4th PDSCHs avoid the resources of the aperiodic ZP CSI-RS in symbols 8-9 of the first and second time slots respectively.

[0056] For example, following the rule of rate matching for PDSCHs with overlapping aperiodic ZP CSI-RS information based on aperiodic ZP CSI-RS information, the base station can configure a set of combinations of aperiodic ZP CSI-RS included in multiple PDSCHs or multiple downlink time units, and indicate one of these combinations through the DCI. Optionally, for DCIs that can only schedule a single PDSCH and those that can schedule multiple PDSCHs, the base station can configure the aperiodic ZP CSI-RS set independently. For example, for a DCI that can only schedule a single PDSCH, the aperiodic ZP CSI-RS set configured by the base station is applicable to one PDSCH. For a DCI that can schedule multiple PDSCHs, the aperiodic ZP CSI-RS set configured by the base station can be applicable to multiple PDSCHs. For example, in a DCI that can schedule multiple PDSCHs, the 2-bit aperiodic ZP CSI-RS indication corresponds to three aperiodic ZP CSI-RS combinations. Combination 1 indicates that the first three PDSCHs each have an aperiodic ZP CSI-RS group, combination 2 indicates that the first PDSCH has an aperiodic ZP CSI-RS group, and combination 3 indicates that all PDSCHs each have an aperiodic ZP CSI-RS group. The base station dynamically indicates different combinations using these 2 bits. If the DCI schedules four PDSCHs and indicates combination 1, then the first three PDSCHs must avoid the indicated aperiodic ZP CSI-RS, while the fourth PDSCH does not need to avoid it.

[0057] If the base station is configured with rate matching information based on the control channel resource set CORESET, then the base station can independently configure the CORESET set for DCIs that can only schedule a single PDSCH and those that can schedule multiple PDSCHs. For example, for a DCI that can only schedule a single PDSCH, the base station's configured CORESET set contains only one CORESET. For a DCI that can schedule multiple PDSCHs, the base station's configured CORESET set contains multiple CORESETs. Based on the time resource information of the configured CORESET set, it is possible to determine which PDSCHs and at which locations within these PDSCHs rate matching will be performed.

[0058] The DCI of the PDCCH can include information about the demodulated reference signal DMRS, indicating the location of DMRS and pattern information. DMRS will be described in further detail below.

[0059] The DCI of the PDCCH can include information about HARQ-ACK / NACK timing.

[0060] Optionally, when multiple PDSCHs are scheduled in a single DCI, the HARQ-ACK / NACK of each PDSCH corresponds to the same uplink time unit. In this case, only one HARQ-ACK / NACK timing information bit field is needed in the DCI. The first or last PDSCH among the scheduled PDSCHs can be used as a time reference, and the uplink time unit can be determined based on the HARQ-ACK / NACK timing information.

[0061] Optionally, the HARQ-ACK / NACK of each PDSCH scheduled by a DCI can correspond to different uplink time units. According to one implementation, only one HARQ-ACK / NACK timing information bit field is needed in the DCI to indicate one HARQ-ACK / NACK timing information, used to determine the uplink time unit of the first PDSCH among the scheduled multiple PDSCHs. The DCI may also include a bit field indicating the time offset of the uplink time unit of each PDSCH, thereby determining the uplink time unit of each PDSCH. Alternatively, the time offset can be configured by higher-layer signaling and does not need to be indicated in the DCI. According to another implementation, only one HARQ-ACK / NACK timing information bit field is needed in the DCI to indicate the HARQ-ACK / NACK timing information of multiple PDSCHs. The base station can configure a set of combinations of HARQ-ACK / NACK timing information of multiple PDSCHs through higher-layer signaling and indicate one of these combinations through the HARQ-ACK / NACK timing information bit field of the DCI.

[0062] The DCI of the PDCCH may include information about the Downlink Assignment Index (DAI). For example, the DCI may include one or more of the first type DAI, second type DAI, and third type DAI described below.

[0063] The first type of DAI, also known as counter-DAI (C-DAI), indicates the sum of the number of PDSCHs scheduled up to the current PDCCH within the HARQ-ACK / NACK feedback binding window; and / or the sum of the number of PDCCHs sent up to the current PDCCH within the HARQ-ACK / NACK feedback binding window. In other words, it is the count information of the PDSCHs scheduled or sent up to the current PDCCH within the HARQ-ACK / NACK feedback binding window.

[0064] Optionally, the sum of the number of PDCCHs transmitted up to the current PDCCH is determined based on the sum of the number of PDCCHs transmitted up to the current carrier and the current PDCCH within the current PDCCH monitoring opportunity. If there are multiple PDCCHs corresponding to the same carrier in the same PDCCH monitoring opportunity, the multiple PDCCHs are counted according to a predefined rule.

[0065] Optionally, the sum of the number of PDSCHs scheduled up to the current PDCCH is determined based on the sum of the PDSCHs scheduled up to the current carrier and the current PDCCH within the current PDCCH monitoring opportunity.

[0066] Optionally, if a DCI can schedule multiple PDSCHs, and the DAI is information indicating the number of PDSCHs, the DAI can be information indicating the first PDSCH scheduled by this PDCCH, or information indicating the last PDSCH scheduled by this PDCCH.

[0067] The second type of DAI, also known as Total DAI or T-DAI, indicates the sum of the number of PDSCHs scheduled up to the current PDCCH monitoring opportunity within the HARQ-ACK / NACK feedback binding window; and / or the sum of the number of PDCCHs sent up to the current PDCCH monitoring opportunity within the HARQ-ACK / NACK feedback binding window. In other words, it's the count information of the PDSCHs scheduled or sent up to the current PDCCH monitoring opportunity within the HARQ-ACK / NACK feedback binding window.

[0068] Optionally, when a user is configured to operate in a multi-carrier state, or is configured to simultaneously receive downlink data on multiple bandwidth parts (BWPs) or subbands (e.g., LBT sub-bands), the sum of the number of PDSCHs scheduled up to the current PDCCH monitoring opportunity is determined by the sum of the number of PDSCHs scheduled by the PDCCH within all carriers, BWPs, and / or subbands that transmit PDCCHs up to the current PDCCH monitoring opportunity.

[0069] Optionally, when a user is configured to operate in multi-carrier mode or is configured to simultaneously receive downlink data on multiple bandwidth portions (BWPs) or subbands (e.g., LBT sub-bands), the sum of the number of PDCCHs transmitted up to the current PDCCH monitoring opportunity is determined by the sum of the number of all PDCCHs transmitted on all carriers, BWPs, and / or subbands within the PDCCH monitoring opportunity up to that PDCCH monitoring opportunity.

[0070] The third type of DAI, also known as the total DAI or T-DAI, is used to indicate the sum of the number of PDCCHs corresponding to HARQ-ACK / NACKs reported on the PUSCH; and / or the sum of the number of PDSCHs corresponding to HARQ-ACK / NACKs reported on the PUSCH.

[0071] Alternatively, to reduce the number of DAI bits, a modulo operation can be used to represent a larger actual range of DAI values ​​with a finite number of DAI bits. For example, with 2-bit DAI, if T-DAI = 9, a modulo 4 operation is required, resulting in 1.

[0072] Alternatively, to reduce the number of DAI bits, the actual value of DAI can be represented using a coarser granularity. The relationship between the DAI bit value and the actual DAI value is, for example, DAI bit value × DAI granularity. For instance, if the DAI granularity is 4, then 2 bits of DAI represent 4, 8, 12, and 16 respectively. This method can be used in conjunction with the modulo method. Therefore, the actual DAI value range can be 4, 8, 12, 16, 20…

[0073] It should be noted that the above DAI count is performed on each PDCCH and / or PDSCH that feeds back HARQ-ACK / NACK in the same uplink time unit.

[0074] If PDSCH needs to be grouped, the DAI count mentioned above is performed on each PDCCH and / or PDSCH within the same PDSCH group that feeds back HARQ-ACK / NACK in the same uplink time unit. When multiple PDSCHs scheduled by a single PDCCH belong to one or more PDSCH groups, the DAI may include one or more DAI bit fields, each corresponding to the DAI information of a PDSCH group. PDSCH grouping will be further described below.

[0075] Optionally, when PDSCHs are grouped, the DCI of the PDCCH can contain multiple sets of Type I DAI and Type II DAI, representing the PDCCH and / or PDSCH counts within each PDSCH group, respectively. For example, the base station is configured with two PDSCH groups, where PDSCH group 1 contains PDSCHs transmitted at the granularity of translation blocks (TBs), and PDSCH group 2 contains PDSCHs transmitted at the granularity of coding block groups (CBGs). If a DCI can schedule multiple PDSCHs, and the transmission granularity of each PDSCH can be different, then this DCI contains two sets of Type I DAI and Type II DAI, respectively indicating the DAI information of each PDSCH within its corresponding PDSCH group. For example, if a DCI schedules four PDSCHs (PDSCH 1, PDSCH 2, PDSCH 3, and PDSCH 4), where PDSCH 1, PDSCH 2, and PDSCH 3 belong to PDSCH group 1, and PDSCH 4 belongs to group 2, then the first group T-DAI = 3 indicates that PDSCH group 1 has 3 PDSCHs, and the second group T-DAI = 1 indicates that PDSCH group 2 has 1 PDSCH. If a DCI can only schedule PDSCHs belonging to one PDSCH group, then the DCI only needs to contain one set of first-class DAI and one set of second-class DAI to represent the DAI count within that PDSCH group.

[0076] The HARQ-ACK / NACK feedback binding window is determined by the set of all downlink time units that can simultaneously provide HARQ-ACK / NACK feedback in the same uplink time unit, and / or the set of all carriers. The uplink / downlink time unit can be one or more time slots, mini-time slots, sub-time slots, or OFDM symbols.

[0077] According to one embodiment, before the terminal 10 sends the hybrid automatic repeat request response (HARQ-ACK / NACK) codebook for the PDSCH to the base station 20, the terminal 10 may determine the uplink time unit for the HARQ-ACK / NACK of the feedback PDSCH based on the PDCCH and PDSCH received from the base station 20, and send the HARQ-ACK / NACK codebook in the uplink time unit.

[0078] The uplink timing unit for sending the HARQ-ACK / NACK codebook is determined, for example, by the HARQ-ACK / NACK timing indicated by the PDCCH. Optionally, the HARQ-ACK / NACK timing used to determine the uplink timing unit for sending the HARQ-ACK / NACK codebook is determined by higher-layer signaling configuration and / or by predefined rules, for example, based on the minimum delay for the UE to process the PDSCH.

[0079] Optionally, the HARQ-ACK / NACK of each PDSCH scheduled by a PDCCH corresponds to the same uplink time unit. Optionally, the HARQ-ACK / NACK of each PDSCH scheduled by a PDCCH corresponds to the same or different uplink time units. The maximum number of PDSCHs that can be scheduled for a PDCCH as described below is limited to the maximum number of PDSCHs that can be scheduled to send HARQ-ACK / NACK in the same uplink time unit. For example, a PDCCH can schedule a maximum of 4 PDSCHs. However, if the base station configures the HARQ-ACK / NACK of these 4 PDSCHs to belong to different PUCCHs, then in the following calculation of HARQ-ACK / NACK feedback, it is calculated as if a PDCCH can schedule a maximum of 1 PDSCH. For example, if a PDCCH can schedule a maximum of 4 PDSCHs, and these 4 PDSCHs feed back HARQ-ACK / NACK in the same PUCCH, then the following calculation of HARQ-ACK / NACK feedback will be performed based on the assumption that a PDCCH can schedule a maximum of 4 PDSCHs.

[0080] The HARQ-ACK / NACK feedback binding window can be determined by the set of all downlink time units that can simultaneously provide HARQ-ACK / NACK feedback in the same uplink time unit and / or the set of all carriers. The uplink / downlink time unit can be one or more time slots, mini-time slots, sub-time slots, or OFDM symbols.

[0081] According to one embodiment, transmitting the HARQ-ACK / NACK codebook in an uplink time unit includes: grouping the PDSCHs that will feed back HARQ-ACK / NACK in the uplink time unit; and determining the HARQ-ACK / NACK codebook for each PDSCH group.

[0082] For example, PDSCHs that will provide HARQ-ACK / NACK feedback in the uplink time unit can be grouped according to the DCI format of each PDSCH, or the number of PDSCHs indicated in the DCI, or the number of HARQ-ACK / NACK bits corresponding to a PDSCH scheduled by a PDCCH, the transmission granularity of each scheduled PDSCH, and / or the transmission granularity of the reference PDSCH. Determining the HARQ-ACK / NACK codebook for each PDSCH group may include: determining the HARQ-ACK / NACK codebook for each PDSCH group based on the DAI within this PDSCH group.

[0083] For PDSCH grouping based on the DCI format used to schedule each PDSCH, the base station configures or predefined rules to determine the correspondence between the DCI format and the PDSCH group. Assume that DCI format A allows scheduling of multiple PDSCHs, while DCI format B allows scheduling of only a single PDSCH. Multiple PDSCHs scheduled using DCI format A correspond to different transport blocks (TB). Therefore, PDSCHs scheduled using DCI format A and PDSCHs scheduled using DCI format B belong to different PDSCH groups.

[0084] Optionally, if a UE is configured with multiple DCI formats, the correspondence between each DCI format and PDSCH groups is determined according to base station configuration or predefined rules. For example, if the UE is configured with DCI format C for fallback mode, DCI format B which can only schedule a single PDSCH, and DCI format A which can schedule multiple PDSCHs, then the PDSCHs scheduled by DCI format C and DCI format B are assigned to PDSCH group 1, and the PDSCHs scheduled by DCI format A are assigned to PDSCH group 2.

[0085] For grouping PDSCHs based on the number of PDSCHs indicated in the DCI of each PDSCH, assuming the PDSCH count threshold Th1 is predefined or configured by the base station: If the actual number of PDSCHs X scheduled for a PDCCH is greater than the threshold Th1, then these X PDSCHs belong to PDSCH group i; if X is less than or equal to the threshold Th1, then these X PDSCHs belong to PDSCH group j, where i ≠ j.

[0086] For example, if Th1 = 1, PDCCH 1 schedules 4 PDSCHs (PDSCH 1 to 4), and PDCCH 2 schedules 1 PDSCH (PDSCH 5), then PDSCH 1 to 4 and PDSCH 5 belong to different PDSCH groups. In this example, the DCI formats of PDCCH 1 and PDCCH 2 can be the same or different. For example, the DCI formats of PDCCH 1 and PDCCH 2 can both be DCI format A, or they can be different, one being DCI format A and the other being DCI format B.

[0087] For determining PDSCH groups based on the number of HARQ-ACK / NACK bits corresponding to a PDSCH scheduled by a PDCCH, assume that the HARQ-ACK / NACK bit threshold Th2 is predefined or configured by the base station. If the sum of the HARQ-ACK / NACK bits corresponding to all X PDSCHs scheduled by a PDCCH is greater than Th2, then these X PDSCHs belong to PDSCH group i; if X is less than or equal to the threshold Th2, then these X PDSCHs belong to PDSCH group j, where i ≠ j.

[0088] For example, if Th2 = 4 bits, PDCCH 1 schedules two PDSCHs, namely PDSCH 1 and PDSCH 2. PDSCH 1 is based on TB transmission, and PDSCH 2 is based on coded block groups (CBGs), actually scheduling 2 CBGs. PDCCH 2 schedules one PDSCH 3, which is also based on CBGs, actually scheduling 8 CBGs. PDCCH 3 schedules two PDSCHs, namely PDSCH 4 and PDSCH 5. PDSCH 4 and PDSCH 5 are both based on CBGs, actually scheduling 4 CBGs. Therefore, the total number of bits for PDSCH 1 / 2 does not exceed 4 bits, belonging to PDSCH group 1; the total number of bits for PDSCH 3 and PDSCH 4 / 5 exceeds 4 bits, belonging to PDSCH group 2.

[0089] For determining PDSCH packets based on the granularity of a PDSCH transmission scheduled by a PDCCH and / or the HARQ-ACK / NACK feedback of the PDSCH, assuming the UE is configured to operate on at least one carrier in a scheduling and HARQ-ACK / NACK feedback mode based on the coded block group (CBG), the PDSCH packets are determined based on whether the PDSCH is based on the CBG or the transport block (TB).

[0090] Optionally, if a PDCCH can schedule multiple PDSCHs, and the transmission granularity of each PDSCH scheduled by this PDCCH is the same, then the PDSCH packets of all PDSCHs scheduled by this PDCCH can be determined according to the transmission granularity, and all PDSCHs belong to the same PDSCH packet.

[0091] Optionally, if a PDCCH can schedule multiple PDSCHs, and the transmission granularity of each PDSCH scheduled by this PDCCH may be different, then the PDSCH packets of each PDSCH can be determined according to the transmission granularity of each PDSCH, and each PDSCH may belong to different PDSCH packets.

[0092] Optionally, if a PDCCH can schedule multiple PDSCHs, and the transmission granularity of each PDSCH scheduled by this PDCCH may be different, then the PDSCH packets of all PDSCHs scheduled by this PDCCH are determined according to the transmission granularity of a reference PDSCH, and all PDSCHs belong to the same PDSCH packet. That is, even if the transmission granularity of each PDSCH is different, all PDSCHs will be grouped into the same PDSCH packet, and the specific packet is determined according to the reference PDSCH packet. The reference PDSCH is predefined, determined according to predefined rules, or semi-statically configured. Alternatively, the transmission granularity of the reference PDSCH is predefined, determined according to predefined rules, or semi-statically configured. For example, if a PDCCH schedules two PDSCHs, one based on TB transmission and the other based on CBG transmission, then these two PDSCHs can belong to the same PDSCH group; when the transmission granularity of the reference PDSCH is CBG, both PDSCHs belong to the CBG transmission PDSCH group.

[0093] Determining the HARQ-ACK / NACK codebook for each PDSCH group based on the DAI within that group can include: determining the HARQ-ACK / NACK codebook for the PDSCH group based on the DAI within that group and the number of HARQ-ACK / NACK bits corresponding to each PDSCH within that group. Specifically, the HARQ-ACK / NACK codebook for the PDSCH group can be determined using one of the following methods:

[0094] Method 1: Within a PDSCH group, the number of HARQ-ACK / NACK bits N for each PDSCH. max_p It is a predefined or base station-configured maximum number of PDSCHs N belonging to this PDSCH group, which can be scheduled by a PDCCH. max_pdsch It is predefined or configured by the base station. If DAI counts PDCCH, then the number of HARQ-ACK / NACK bits corresponding to one PDCCH is N. t =N max_p ×N max_pdsch Based on the actual DAI value M within this PDSCH group, the total number of bits in the HARQ-ACK / NACK codebook is determined to be M×N. t =M×N max_p ×N max_pdsch Alternatively, if DAI counts PDSCH, then the number N HARQ-ACK / NACK bits corresponding to one PDSCH is... t =N max_pWhen the DAI value M is the information of the last PDSCH among multiple PDSCHs scheduled by DCI, the total number of bits in the HARQ-ACK / NACK codebook is determined to be M×N based on the actual DAI value M within this PDSCH group. t =M×N max_p Optionally, if DAI counts PDSCHs, and the value M of DAI is the information of the first PDSCH in the n PDSCHs scheduled by DCI, then based on the actual value M of DAI within this PDSCH group, the total number of bits in the HARQ-ACK / NACK codebook is determined to be (M+n-1)×N. t = (M+n-1)×N max_p .

[0095] Method 2: Within a PDSCH group, the number N of HARQ-ACK / NACK bits corresponding to a PDCCH. t It is predefined or configured by the base station. If DAI counts the PDCCH, the total number of bits in the HARQ-ACK / NACK codebook is determined to be M×N based on the actual DAI value M within this PDSCH group. t Optionally, the base station must ensure that the number of HARQ-ACK / NACK bits N corresponding to one PDCCH is [number missing] during scheduling. t Not less than the sum of the HARQ-ACK / NACK bits of each PDSCH actually scheduled by this PDCCH. Where Ni is the number of HARQ-ACK / NACK bits in the i-th PDSCH. For example, if the UE is configured to operate dynamically on CBG-based or TB-based transmissions, Ni may be different for each PDSCH.

[0096] Optionally, if the UE is configured to transmit up to L TBs within at least one frequency domain or time unit, then the number of HARQ-ACK / NACK bits N in a PDSCH is... max_p The number of HARQ-ACK / NACK bits per TB is determined by L and the number of HARQ-ACK / NACK bits per TB. For example, if configured for CBG-based transmission, the number of HARQ-ACK / NACK bits per TB would be N. max_cbg If configured for TB-based transmission, the number of HARQ-ACK / NACK bits per TB is 1.

[0097] The HARQ-ACK / NACK codebook for transmitting PDSCH in the uplink time unit further includes: concatenating all groups of HARQ-ACK / NACK codebooks in a predetermined order to form a single HARQ-ACK / NACK codebook, and transmitting the corresponding HARQ-ACK / NACK information via a PUCCH or PUSCH. Optionally, transmitting the HARQ-ACK / NACK codebook for PDSCH in the uplink time unit includes: transmitting the HARQ-ACK / NACK information corresponding to each group of HARQ-ACK / NACK codebooks via their respective PUCCH or PUSCH.

[0098] The steps described above, the DAI counting according to PDSCH or PDCCH, the grouping method of PDSCH, and the various ways to determine the HARQ-ACK / NACK codebook for each PDSCH group based on the DAI within the PDSCH group can be combined to obtain different implementations for determining the HARQ-ACK / NACK codebook. Several specific examples are given below, but are not limited to these.

[0099] Example 1: Determine the PDSCH grouping based on the number of PDSCHs indicated in the DCI of each PDSCH. If the DCI of a PDCCH indicates 1 PDSCH, it is PDSCH group 1; if the DCI of a PDCCH indicates more than 1 PDSCH, it is PDSCH group 2. Assume that in PDSCH group 1, a PDCCH actually schedules 1 PDSCH, and each PDSCH corresponds to 1 bit of HARQ-ACK / NACK. In PDSCH group 2, a PDCCH corresponds to N bits of HARQ-ACK / NACK. t=4, the maximum number of PDSCHs that can be scheduled for a PDCCH is X=4, and each PDSCH corresponds to 1 bit of HARQ-ACK / NACK. If the actual number of PDSCHs scheduled for a PDCCH is less than 4, a placeholder bit is sent until the total number of HARQ-ACK / NACK bits corresponding to this PDCCH is 4. In the DCI of the PDCCH that schedules the PDSCH, there are two types of DAI, which represent the sum of the number of PDCCHs sent up to the current PDCCH within the HARQ-ACK / NACK feedback binding window, and the sum of the number of PDCCHs sent up to the PDCCH monitoring opportunity where the current PDCCH is located, respectively. The first type of DAI and the second type of DAI are counted in the two PDSCH groups respectively. So, for PDSCH group 1, if the actual value of the second type of DAI of the last PDSCH in the binding window is M1, then the total number of bits of the HARQ-ACK / NACK codebook of PDSCH group 1 is M1. For PDSCH group 2, if the actual value of the second type DAI in the last PDSCH within the binding window is M2, then the total number of bits in the HARQ-ACK / NACK codebook of PDSCH group 2 is M2×4. Concatenating the HARQ-ACK / NACK codebooks of PDSCH group 1 and PDSCH group 2 results in a total of M1+M2×4 bits of HARQ-ACK / NACK.

[0100] Figure 2 An example of the HARQ-ACK / NACK feedback binding window and HARQ-ACK / NACK codebook based on Example 1 is shown. Figure 2As shown, the base station configures three carriers for the UE. Within the HARQ-ACK / NACK binding window, in the first PDCCH monitoring opportunity, the UE detects PDCCH on all three carriers. Specifically, carrier 1's PDCCH is scheduled as PDSCH 1, which belongs to PDSCH group 1. C-DAI = 1 indicates that this PDCCH is the first PDCCH belonging to PDSCH group 1 in this PDCCH monitoring opportunity, and T-DAI = 1 indicates that there is only one PDCCH in PDSCH group 1 in this PDCCH monitoring opportunity. Carrier 2's PDCCH is scheduled as PDSCH 2–5, which belong to PDSCH group 2. C-DAI = 1 indicates that this PDCCH is the first PDCCH belonging to PDSCH group 2 in this PDCCH monitoring opportunity, and T-DAI = 2 indicates that there are two PDCCHs in PDSCH group 2 in this PDCCH monitoring opportunity. Carrier 3's PDCCH schedules PDSCH 6-9, which belong to PDSCH group 2. C-DAI = 2, indicating that this PDCCH is the second PDCCH belonging to PDSCH group 2 in this PDCCH monitoring opportunity, and T-DAI = 2, indicating that there are 2 PDCCHs in PDSCH group 2 in this PDCCH monitoring opportunity. Then, in the next PDCCH monitoring opportunity, the UE monitors PDCCHs on both carriers (carrier 1 and carrier 3). Carrier 1's PDCCH schedules PDSCH 10-11, which belong to PDSCH group 2. C-DAI = 3, indicating that this PDCCH is the third PDCCH belonging to PDSCH group 2 up to this PDCCH monitoring opportunity, and T-DAI = 4, indicating that there are 4 PDCCHs in PDSCH group 2 up to this PDCCH monitoring opportunity. Carrier 3's PDCCH schedules PDSCH 12-15, which belong to PDSCH group 2. C-DAI = 4, indicating that this PDCCH is the fourth PDCCH belonging to PDSCH group 2 up to this PDCCH monitoring opportunity, and T-DAI = 4, indicating that there are 4 PDCCHs in PDSCH group 2 up to this PDCCH monitoring opportunity. Then, in the next PDCCH monitoring opportunity, the UE monitors a PDCCH on one carrier (carrier 2). Carrier 1's PDCCH schedules PDSCH 16, which belongs to PDSCH group 1. C-DAI = 2, indicating that this PDCCH is the second PDCCH belonging to PDSCH group 1 up to this PDCCH monitoring opportunity, and T-DAI = 2, indicating that there are 2 PDCCHs in PDSCH group 1 up to this PDCCH monitoring opportunity.Therefore, when the UE generates its codebook, the HARQ-ACK / NACK codebook 1 of PDSCH group 1 contains 2 bits of HARQ-ACK / NACK, which are the HARQ-ACK / NACK bits for PDSCH 1 and PDSCH 16 respectively. The HARQ-ACK / NACK codebook 2 of PDSCH group 2 contains 16 bits of HARQ-ACK / NACK, which are the HARQ-ACK / NACK bits for PDSCH 2 to 15 respectively, and 2 bits of HARQ-ACK / NACK bits used as placeholders. The 2 placeholder bits are located after the HARQ-ACK / NACK bits for PDSCH 10 and 11, making the number of HARQ-ACK / NACK bits corresponding to one PDCCH 4.

[0101] Example 2: Determine PDSCH grouping based on the granularity of PDSCH transmissions scheduled by a PDCCH and / or HARQ-ACK / NACK feedback for PDSCHs. Assuming the base station only configures TB-based transmissions, all PDSCHs belong to the same group. The DCI of the PDCCH scheduling PDSCHs includes a first type DAI and a second type DAI, representing the sum of the number of PDSCHs transmitted up to the current PDCCH within the HARQ-ACK / NACK feedback binding window, and the sum of the number of PDSCHs transmitted up to the PDCCH monitoring opportunity where the current PDCCH resides, respectively. Therefore, if the actual value of the second type DAI for the last PDSCH within the binding window is M1, the total number of bits in the HARQ-ACK / NACK codebook is M1 (assuming the base station is configured to transmit only one TB per PDSCH).

[0102] Figure 3 An example of the HARQ-ACK / NACK feedback binding window and HARQ-ACK / NACK codebook based on Example 2 is shown. Figure 3As shown, the base station configured three carriers for the UE. Within the HARQ-ACK / NACK binding window, in the first PDCCH monitoring opportunity, the UE detected PDCCH on all three carriers. Specifically, carrier 1's PDCCH schedules PDSCH 1. C-DAI = 1, indicating this is the first PDSCH scheduled in this PDCCH monitoring opportunity, and T-DAI = 1, indicating the total number of PDSCHs scheduled in this PDCCH monitoring opportunity is 9. Carrier 2's PDCCH schedules PDSCHs 2-5. C-DAI = 2, indicating this is the second PDSCH scheduled in this PDCCH monitoring opportunity, and T-DAI = 9, indicating the total number of PDSCHs scheduled in this PDCCH monitoring opportunity is 9. Carrier 3's PDCCH schedules PDSCHs 6-9. C-DAI = 6, indicating this is the sixth PDSCH scheduled in this PDCCH monitoring opportunity, and T-DAI = 9, indicating the total number of PDSCHs scheduled in this PDCCH monitoring opportunity is 9. Then, in the next PDCCH monitoring opportunity, the UE detects PDCCH on both carriers (carrier 1 and carrier 3). Carrier 1's PDCCH schedules PDSCH 10-11. C-DAI = 10, indicating this is the 10th PDSCH scheduled up to this PDCCH monitoring opportunity, and T-DAI = 15, indicating the total number of PDSCHs scheduled up to this PDCCH monitoring opportunity is 15. Carrier 3's PDCCH schedules PDSCH 12-15. C-DAI = 4, indicating this is the 12th PDSCH scheduled up to this PDCCH monitoring opportunity, and T-DAI = 15, indicating the total number of PDSCHs scheduled up to this PDCCH monitoring opportunity is 15. Then, in the next PDCCH monitoring opportunity, the UE detects PDCCH on one carrier (carrier 2). Carrier 1's PDCCH schedules PDSCH 16. C-DAI = 16 indicates that this PDSCH is the 16th PDSCH scheduled up to this PDCCH monitoring opportunity, and T-DAI = 16 indicates that the total number of PDSCHs scheduled up to this PDCCH monitoring opportunity is 16. Therefore, when the UE generates its codebook, it only generates one HARQ-ACK / NACK codebook, containing 16 bits of HARQ-ACK / NACK, representing the HARQ-ACK / NACK bits for PDSCHs 1 through 16. The actual DAI values ​​are shown in the diagram. The method in Example 2 saves more HARQ-ACK / NACK overhead than the method in Example 1, but to achieve the same robustness—for example, to ensure that the HARQ-ACK / NACK codebook is not affected by the loss of a certain number of PDCCHs—Example 2 requires more DAI bits.

[0103] Example 3: Determine PDSCH groups based on the granularity of PDSCH transmissions scheduled by a PDCCH and / or PDSCH HARQ-ACK / NACK feedback. Assuming the base station only configures TB-based transmissions, all PDSCHs belong to the same group. The DCI of the PDCCH scheduling PDSCH includes a first type DAI and a second type DAI, representing the sum of the number of PDCCHs transmitted up to the current PDCCH within the HARQ-ACK / NACK feedback binding window, and the sum of the number of PDCCHs transmitted up to the PDCCH monitoring opportunity where the current PDCCH resides, respectively. Assume that a PDCCH corresponds to N HARQ-ACK / NACK bits. t Configured by the base station, N t =4, the maximum number of PDSCHs that can be scheduled for a PDCCH is X=4, and each PDSCH corresponds to 1 bit of HARQ-ACK / NACK. If the actual number of PDSCHs scheduled for a PDCCH is less than 4, a placeholder bit is sent until the total number of HARQ-ACK / NACK bits corresponding to this PDCCH is 4. Therefore, if the actual value of the second type DAI of the last PDSCH in the binding window is M1, then the total number of bits in the HARQ-ACK / NACK codebook is M1×4.

[0104] Figure 4 An example of the HARQ-ACK / NACK feedback binding window and HARQ-ACK / NACK codebook based on Example 3 is shown. Figure 4As shown, the base station configures 3 carriers for the UE. Within the HARQ-ACK / NACK binding window, in the first PDCCH monitoring opportunity, the UE monitors PDCCH on all 3 carriers. Specifically, carrier 1's PDCCH scheduling is PDSCH 1. C-DAI = 1 indicates that this is the first PDCCH scheduled in this PDCCH monitoring opportunity, and T-DAI = 3 indicates that the total number of PDCCHs in this PDCCH monitoring opportunity is 3. Carrier 2's PDCCH scheduling is PDSCH 2-5. C-DAI = 2 indicates that this is the second PDCCH in this PDCCH monitoring opportunity, and T-DAI = 3 indicates that the total number of PDCCHs in this PDCCH monitoring opportunity is 3. Carrier 3's PDCCH scheduling is PDSCH 6-9. C-DAI = 3 indicates that this is the third PDCCH in this PDCCH monitoring opportunity, and T-DAI = 3 indicates that the total number of PDCCHs in this PDCCH monitoring opportunity is 3. Then, in the next PDCCH monitoring opportunity, the UE detects PDCCH on both carriers (carrier 1 and carrier 3). Carrier 1's PDCCH scheduling is PDSCH 10-11. C-DAI = 4, indicating this is the 4th PDCCH up to this monitoring opportunity; T-DAI = 5, indicating the total number of PDCCHs up to this monitoring opportunity is 5. Carrier 3's PDCCH scheduling is PDSCH 12-15. C-DAI = 5, indicating this is the 5th PDCCH up to this monitoring opportunity; T-DAI = 5, indicating the total number of PDCCHs up to this monitoring opportunity is 5. Then, in the next PDCCH monitoring opportunity, the UE detects PDCCH on one carrier (carrier 2). Carrier 2's PDCCH scheduling is PDSCH 16. C-DAI = 6 indicates that this PDCCH is the 6th PDCCH up to this monitoring opportunity, and T-DAI = 6 indicates that the total number of PDCCHs up to this monitoring opportunity is 6. Therefore, when the UE generates the codebook, it only generates one HARQ-ACK / NACK codebook, containing 24 bits of HARQ-ACK / NACK, which are the HARQ-ACK / NACK bits for PDSCH 1 to 16.In this method, each PDCCH corresponds to 4 bits of HARQ-ACK / NACK. The 4 bits corresponding to the PDCCH scheduling PDSCH 1 are the HARQ-ACK / NACK of PDSCH 1 and 3 placeholder bits. The 4 bits corresponding to the PDCCH scheduling PDSCH 10 and 11 are the HARQ-ACK / NACK of PDSCH 10 and 11 and 2 placeholder bits. The 4 bits corresponding to the PDCCH scheduling PDSCH 16 are the HARQ-ACK / NACK of PDSCH 16 and 3 placeholder bits. The method in Example 3 saves more DAI overhead than the method in Example 2, but the HARQ-ACK / NACK overhead is significantly increased. The method in Example 3 is simpler and more robust than the method in Example 1, but the HARQ-ACK / NACK overhead is significantly increased.

[0105] Example 4: PDSCH packets are determined based on the granularity of PDSCH transmissions scheduled by a PDCCH and / or the HARQ-ACK / NACK feedback of the PDSCH. Assume the UE is configured to operate on at least one carrier in a scheduling and HARQ-ACK / NACK feedback mode based on the coded block group (CBG) granularity. The PDSCH packet is determined based on whether the PDSCH is based on a CBG or a transport block (TB). If the PDSCH transmission granularity is TB, it is PDSCH group 1; if the PDSCH transmission granularity is CBG, it is PDSCH group 2. Assume a PDCCH can schedule multiple PDSCHs, and all PDSCHs scheduled by this PDCCH have the same transmission granularity, all being TB-based transmissions. Then, all PDSCHs of this type belong to PDSCH group 1. In the DCI of the PDCCH that schedules PDSCHs, there are two types of DAIs: Type I DAI and Type II DAI. Type I DAI represents the sum of the number of PDSCHs sent up to the current PDCCH within the HARQ-ACK / NACK feedback binding window, and Type II DAI represents the sum of the number of PDSCHs sent up to the current PDCCH monitoring opportunity. Type I DAI and Type II DAI are counted in two PDSCH groups respectively. In PDSCH group 1, each PDSCH corresponds to 1 bit of HARQ-ACK / NACK (assuming the base station is configured to send only one TB per PDSCH). In PDSCH group 2, each PDSCH corresponds to N bits of HARQ-ACK / NACK. max_cbg (The maximum number of CBGs that a TB can be divided into). Therefore, if the actual value of the second type DAI in the last PDSCH within the binding window is M2, then the total number of bits in the HARQ-ACK / NACK codebook is M2 × N. max_cbg(Assume the base station is configured to send only one TB via a PDSCH).

[0106] Example 5: PDSCH packets are determined based on the granularity of PDSCH transmissions scheduled by a PDCCH and / or the HARQ-ACK / NACK feedback of the PDSCH. Assume the UE is configured to operate on at least one carrier in a scheduling and HARQ-ACK / NACK feedback mode based on the coded block group (CBG) granularity. The PDSCH packet is determined based on whether the PDSCH is based on a CBG or a transport block (TB). If the PDSCH transmission granularity is TB, it is PDSCH group 1; if the PDSCH transmission granularity is CBG, it is PDSCH group 2. Assume a PDCCH can schedule multiple PDSCHs, and all PDSCHs scheduled by this PDCCH have the same transmission granularity, namely, TB-based transmissions. Then, all PDSCHs of this type belong to PDSCH group 1. In the DCI of the PDCCH that schedules the PDSCH, there are two types of DAI: Type I DAI and Type II DAI. Type I DAI represents the sum of the number of PDCCHs sent up to the current PDCCH within the HARQ-ACK / NACK feedback binding window, and Type II DAI represents the sum of the number of PDCCHs sent up to the PDCCH monitoring opportunity at the current PDCCH location. Type I DAI and Type II DAI are counted in two PDSCH groups respectively. Within PDSCH group 1, the number of HARQ-ACK / NACK bits N corresponding to each PDCCH is... t The maximum number of PDSCHs that can be scheduled for a PDCCH is X = 4, and each PDSCH corresponds to 1 bit of HARQ-ACK / NACK. Therefore, if the actual value of the second type DAI of the last PDSCH within the binding window is M1, the total number of bits in the HARQ-ACK / NACK codebook is M1 × 4 (assuming the base station is configured to send only one TB per PDSCH). For PDCCHs with fewer than 4 scheduled PDSCHs, such as PDCCHs with only one scheduled PDSCH, or PDCCHs of DCIs operating in backoff mode, placeholder bits are needed until the 4-bit HARQ-ACK / NACK is satisfied. Within PDSCH group 2, the number of HARQ-ACK / NACK bits N corresponding to each PDCCH is... t For N max_cbg (The maximum number of CBGs that a TB can be divided into). Therefore, if the actual value of the second type DAI in the last PDSCH within the binding window is M2, then the total number of bits in the HARQ-ACK / NACK codebook is M2 × N. max_cbg (Assume the base station is configured to send only one TB via a PDSCH).

[0107] In this scenario, a specific implementation involves binding the HARQ-ACK / NACK bits of multiple PDSCHs scheduled by a single PDCCH. This is achieved by performing a bitwise AND operation on the HARQ-ACK / NACK bits of all these PDSCHs, resulting in a 1-bit HARQ-ACK / NACK. Therefore, within PDSCH group 1, each PDCCH corresponds to N bits of HARQ-ACK / NACK. t Assuming the base station is configured with a PDSCH, it can only send one TB (1 bit).

[0108] Example 6: Determining PDSCH packets based on the granularity of PDSCH transmissions scheduled by a PDCCH and / or HARQ-ACK / NACK feedback for PDSCHs. Assume the UE is configured to operate on at least one carrier in a scheduling and HARQ-ACK / NACK feedback mode based on coded block group (CBG) granularity. PDSCH packets are determined based on whether the PDSCH is based on a CBG or a transport block (TB). If the PDSCH transmission granularity is TB, it is PDSCH group 1; if the PDSCH transmission granularity is CBG, it is PDSCH group 2. Assume a PDCCH can schedule multiple PDSCHs, and the transmission granularity of each PDSCH scheduled by this PDCCH can be different, and the PDSCH packets for each PDSCH are determined according to their respective transmission granularities.

[0109] Optionally, the DCI of the PDCCH that schedules PDSCHs can include two sets of first-class DAI and second-class DAI, representing the PDSCH counts within the two PDSCH groups, respectively. In each DAI bit field, the first-class DAI represents the sum of the number of PDSCHs scheduled up to the current PDCCH within the HARQ-ACK / NACK feedback binding window, and the sum of the number of PDSCHs scheduled up to the PDCCH monitoring opportunity where the current PDCCH resides. The first-class DAI and second-class DAI are counted within the two PDSCH groups, respectively. If all PDSCHs belong to one PDSCH packet in a single scheduling, the DAI bit field of the other PDSCH packet can be set to a predefined value, such as a special value or the same as the DAI value in the previously received PDCCH, or T-DAI being the actual value, C-DAI being a special value or the same as the previous DAI value or the next DAI value, or the value being unrestricted but the UE does not determine the HARQ-ACK / NACK codebook based on this value.

[0110] Within PDSCH group 1, if the actual value of the second type DAI of the last PDSCH within the binding window is M1, then the total number of bits in the HARQ-ACK / NACK codebook is M1 (assuming the base station is configured to send only one TB per PDSCH). Conversely, if the actual value of the second type DAI of the last PDSCH within the binding window is M2, then the total number of bits in the HARQ-ACK / NACK codebook is M2 (assuming the base station is configured to send only one TB per PDSCH).

[0111] Figure 5 An example of a HARQ-ACK / NACK feedback binding window and a HARQ-ACK / NACK codebook based on Example Six is ​​shown. Figure 5 As shown, the base station configures three carriers for the UE. Within the HARQ-ACK / NACK binding window, during the first PDCCH monitoring opportunity, the UE detects PDCCH on all three carriers. Assume carrier 1 is configured to support only TB-based transmission granularity, with each PDSCH feeding back 1 bit of HARQ-ACK / NACK. Carriers 2 and 3 are configured to support CBG-based transmission granularity, with each CBG-based PDSCH feeding back N bits. max_cbg= 2 bits, each TB-based PDSCH feedback 1 bit HARQ-ACK / NACK. Carrier 1's PDCCH schedules PDSCH1, belonging to PDSCH group 1. C-DAI = 1, indicating this PDSCH is the first PDSCH scheduled in this PDCCH monitoring opportunity, and T-DAI = 6, indicating the total number of PDSCHs in this PDCCH monitoring opportunity is 6. Carrier 2's PDCCH schedules PDSCHs 2-5. PDSCHs 2, 3, and 5 are TB-based transmissions, and PDSCH 4 is a CBG-based transmission. Therefore, PDSCHs 2, 3, and 5 belong to PDSCH group 1, and PDSCH 4 belongs to PDSCH group 2. Group 1 has C-DAI = 2 and T-DAI = 6, while Group 2 has C-DAI = 1 and T-DAI = 3. Carrier 3's PDCCH schedules PDSCH 6-9, indicating that PDSCH 6 and 7 are CBG-based transmissions, and PDSCH 8 and 9 are TB-based transmissions. Therefore, PDSCH 8 and 9 belong to PDSCH group 1, and PDSCH 6 and 7 belong to PDSCH group 2. Group 1 has C-DAI = 5 and T-DAI = 6, while Group 2 has C-DAI = 2 and T-DAI = 3. Then, in the next PDCCH monitoring opportunity, the UE detects PDCCH on both carriers (carrier 1 and carrier 3). Carrier 1's PDCCH schedules PDSCH 10-11, belonging to PDSCH group 1, with C-DAI = 7 and T-DAI = 11. Carrier 3's PDCCH schedules PDSCH 12-15, indicating that PDSCH 12-14 are TB-based transmissions and PDSCH 15 is a CBG-based transmission. Therefore, PDSCH 12-14 belong to PDSCH group 1, and PDSCH 15 belongs to PDSCH group 2. Group 1 has C-DAI = 9 and T-DAI = 11, while Group 2 has C-DAI = 4 and T-DAI = 4. Then, in the next PDCCH monitoring opportunity, the UE detects a PDCCH on one carrier (carrier 2). Carrier 2's PDCCH schedules PDSCH 16. This PDCCH supports a maximum of one PDSCH scheduling and contains only one DAI bit field, indicating the DAI of its PDSCH group. The base station indicates that PDSCH 16 is a CBG-based transmission; therefore, PDSCH 16 belongs to PDSCH group 2. C-DAI = 5 and T-DAI = 5. Therefore, when generating the codebook, the UE generates two HARQ-ACK / NACK codebooks. Codebook 1 includes 11 HARQ-ACK / NACKs for 11 PDSCHs, totaling 11 bits, and codebook 2 includes 5 HARQ-ACK / NACKs for 5 PDSCHs, totaling 10 bits. The total codebook length is 21 bits.

[0112] Example 7: Determining PDSCH packets based on the granularity of PDSCH transmissions scheduled by a PDCCH and / or HARQ-ACK / NACK feedback for PDSCHs. Assume the UE is configured to operate on at least one carrier in a scheduling and HARQ-ACK / NACK feedback mode based on the coded block group (CBG) granularity. The PDSCH packets are determined based on whether the PDSCH is based on a CBG or a transport block (TB). If the PDSCH transmission granularity is TB, it is PDSCH group 1; if the PDSCH transmission granularity is CBG, it is PDSCH group 2. Assume a PDCCH can schedule multiple PDSCHs, and the transmission granularity of each PDSCH scheduled by this PDCCH can be different, and the PDSCH packets for each PDSCH are determined according to their respective transmission granularities.

[0113] Optionally, the DCI of the PDCCH that schedules the PDSCH can include two sets of Type I DAI and Type II DAI, representing the PDCCH counts within the two PDSCH groups, respectively. In each DAI bit field, Type I DAI represents the sum of the number of PDCCHs sent up to the current PDCCH within the HARQ-ACK / NACK feedback binding window, and the sum of the number of PDCCHs sent up to the PDCCH monitoring opportunity where the current PDCCH resides. Type I DAI and Type II DAI are counted within the two PDSCH groups, respectively. If all PDSCHs belong to one PDSCH packet in a single scheduling, the DAI bit field of the other PDSCH packet can be set to a predefined value, or its value can be left undefined but the UE does not determine the HARQ-ACK / NACK codebook based on this value.

[0114] Within PDSCH group 1, each PDCCH corresponds to the number N of HARQ-ACK / NACK bits. t The maximum number N of PDSCHs that can be scheduled based on TB transmissions for a PDCCH. tb_pdsch Each PDSCH corresponds to 1 bit of HARQ-ACK / NACK (assuming the base station is configured to send only one TB per PDSCH). Within PDSCH group 2, each PDCCH corresponds to N bits of HARQ-ACK / NACK. t The maximum number N of CBG-based PDSCHs that can be scheduled by a PDCCH cbg_pdsch The number N of HARQ-ACK / NACK bits per PDSCH max_cbg Determine, for example, N cbg_pdsch ×N max_cbg Each PDSCH corresponds to N. max_cbgBit HARQ-ACK / NACK (assuming the base station is configured to send only one TB via a PDSCH). Optionally, N tb_pdsch This equals the maximum number of PDSCHs that can be scheduled by a PDCCH. Optionally, N tb_pdsch and / or N cbg_pdsch It is predefined or configured by the base station.

[0115] Figure 6 An example of the HARQ-ACK / NACK feedback binding window and HARQ-ACK / NACK codebook based on Example 7 is shown. Figure 6 As shown, the base station configures 3 carriers for the UE. The base station configures a PDCCH with a maximum schedulable number of PDSCHs N = 4, of which at most 2 PDSCHs can be CBG-based transmissions, and the number of PDSCHs based on TB transmissions is not limited. Therefore, N... cbg_pdsch =2, N tb_pdsch =4. Within the HARQ-ACK / NACK binding window, during the first PDCCH monitoring opportunity, the UE detects PDCCH on all three carriers. Assume carrier 1 is configured to support only TB as the transmission granularity, with each PDSCH feeding back 1 bit of HARQ-ACK / NACK. Carriers 2 and 3 are configured to support CBG as the transmission granularity, with each CBG-based PDSCH feeding back N bits. max_cbg= 2 bits, with 1 bit of HARQ-ACK / NACK feedback for each TB-based PDSCH. For carrier 1, PDSCH 1 is scheduled, belonging to PDSCH group 1, with C-DAI = 1, indicating that this PDSCH is the first PDSCH in this PDSCH monitoring opportunity. T-DAI = 3 indicates that the total number of PDSCHs in this PDSCH monitoring opportunity is 3. For carrier 2, PDSCHs 2-5 are scheduled, indicating that PDSCHs 2, 3, and 5 are TB-based transmissions, and PDSCH 4 is a CBG-based transmission. Therefore, PDSCHs 2, 3, and 5 belong to PDSCH group 1, and PDSCH 4 belongs to PDSCH group 2. For group 1, C-DAI = 2 and T-DAI = 3; for group 2, C-DAI = 1 and T-DAI = 2. Carrier 3's PDCCH schedules PDSCH 6-9, indicating that PDSCH 6 and 7 are CBG-based transmissions, and PDSCH 8 and 9 are TB-based transmissions. Therefore, PDSCH 8 and 9 belong to PDSCH group 1, and PDSCH 6 and 7 belong to PDSCH group 2. Group 1 has C-DAI = 3 and T-DAI = 3, while Group 2 has C-DAI = 2 and T-DAI = 2. Then, in the next PDCCH monitoring opportunity, the UE detects PDCCH on both carriers (carrier 1 and carrier 3). Carrier 1's PDCCH schedules PDSCH 10-11, belonging to PDSCH group 1, with C-DAI = 4 and T-DAI = 5. Carrier 3's PDCCH schedules PDSCH 12-15, indicating that PDSCH 12-14 are TB-based transmissions and PDSCH 15 is a CBG-based transmission. Therefore, PDSCH 12-14 belong to PDSCH group 1, and PDSCH 15 belongs to PDSCH group 2. Group 1 has C-DAI = 5 and T-DAI = 5, while Group 2 has C-DAI = 3 and T-DAI = 3. Then, in the next PDCCH monitoring opportunity, the UE detects a PDCCH on one carrier (carrier 2). Carrier 2's PDCCH schedules PDSCH 16. This PDCCH supports a maximum of one PDSCH scheduling and contains only one DAI bit field, indicating the DAI of its PDSCH group. The base station indicates that PDSCH 16 is a CBG-based transmission; therefore, PDSCH 16 belongs to PDSCH group 2. C-DAI = 4 and T-DAI = 4. Therefore, when generating the codebook, the UE generates two HARQ-ACK / NACK codebooks. Codebook 1 includes HARQ-ACK / NACK for 11 PDSCHs scheduled from 5 PDCCHs, with each PDCCH corresponding to 4 bits, for a total of 20 bits. Codebook 2 includes HARQ-ACK / NACK for 4 PDSCHs scheduled from 4 PDCCHs, with each PDCCH corresponding to 2×2=4 bits, for a total of 16 bits. The total codebook length is 36 bits.Example 7 saves DAI overhead compared to Example 6, but increases UCI overhead. This is because for each PDCCH, HARQ-ACK / NACK is generated based on the maximum number of schedulable PDSCHs belonging to this PDSCH group.

[0116] When HARQ-ACK / NACK of PDSCH from multiple carriers or HARQ-ACK / NACK of PDSCH from multiple downlink time units are fed back in one uplink time unit, and the DCI format or the number of PDSCHs scheduled by the DCI indication may be different, the solution according to the above embodiment can avoid the problem of not being able to determine the size or arrangement order of the HARQ-ACK / NACK codebook when the UE misses one or more PDSCHs (PDCCHs) due to the uncertainty of the number of missed PDSCHs.

[0117] According to one embodiment, the terminal 10 receiving PDSCH from the base station 20 based on the received PDCCH further includes receiving a demodulation reference signal DMRS for the PDSCH.

[0118] In this embodiment, the base station predefines a set of one or more DMRS patterns. The base station indicates the DMRS pattern used by one or a type of PDSCH, for example, through higher-layer signaling configuration, physical layer information indication, or system information.

[0119] For example, a base station can represent the pattern of the DMRS by configuring the time-frequency resources where the DMRS resides within a time window. The length and start point of this time window are configurable or predefined.

[0120] Optionally, the starting point of this time window can be referenced to a predefined time point, for example, the starting point of a certain system frame / subframe / slot.

[0121] For example, a DMRS pattern configured by a base station includes periodic information, time offset information, and time length to determine the time slot where the DRMS ​​is located. The base station is also configured to include the DMRS on which symbols within these time slots.

[0122] In practical implementation, the time-frequency resources of the scheduled PDSCH may not contain DMRS, and the scheduled PDSCH may rely on DMRS outside the PDSCH time-frequency resources for channel estimation. For example, the base station schedules PDSCH1-4 through PDCCH1, occupying symbols 1-7, 8-14 of time slot n, and symbols 1-7, 8-14 of time slot n+1, and schedules PDSCH5-8 through PDCCH2, occupying symbols 1-7, 8-14 of time slot n+2, and symbols 1-7, 8-14 of time slot n+3. The DMRS pattern indicated by the base station is symbols 3-4 of time slots n, n+2, n+4, ... Then, the time-frequency resources of PDSCH1 and 3 contain DMRS, while the time-frequency resources of PDSCH2 and 4 do not contain DMRS. Alternatively, the DMRS pattern indicated by the base station may be symbols 3-4 of time slots n, n+4, n+8, ... Therefore, the time-frequency resources of PDSCH1 include DMRS, while the time-frequency resources of PDSCH 2 to 4 do not include DMRS.

[0123] Optionally, the starting point of this time window can be referenced to a specific time point of the scheduled PDSCH. For example, the starting point of this time window can be the time start point of the first PDSCH, or the starting point of this time window can be the starting point of the downlink time unit in which the time start point of the first PDSCH is located, such as the starting point of the downlink time slot in which the time start point of the first PDSCH is located. Alternatively, the starting point of this time window can be referenced to the time start point of each scheduled PDSCH.

[0124] Optionally, the base station configures the offset between the starting point of this time window and the reference time starting point.

[0125] For example, a DMRS pattern configured by a base station includes a symbol location index to determine which symbols, starting from the first PDSCH, contain DMRS. Assume the DMRS pattern is the third symbol in the first time slot and the third symbol in the third time slot. The base station schedules four PDSCHs via a DCI, with each PDSCH occupying one time slot. Therefore, the first time slot of the DMRS pattern is the time slot containing the starting point of PDSCH1. Consequently, the third symbol in PDSCH1 and 3 contains DMRS, while PDSCH2 and 4 do not.

[0126] For example, a DMRS pattern configured by a base station includes a symbol location index to determine which symbols contain DMRS, starting from each PDSCH. Assume the DMRS pattern is the 1st and 6th symbols of a PDSCH. The base station schedules 4 PDSCHs via a DCI, with each PDSCH occupying one time slot. Therefore, for each PDSCH, DMRS is contained in the 1st and 6th symbols of that PDSCH, respectively.

[0127] For example, a DMRS pattern configured by a base station includes a symbol location index and a time offset, used to determine which symbol relative to the PDSCH start point, and which subsequent symbols contain DMRS.

[0128] Optionally, the base station configuration may include additional DMRS. If additional DMRS exists, the location of the additional DMRS is determined individually based on the time-domain information of each scheduled PDSCH; or, the location of the additional DMRS is determined jointly based on the time-domain information of all PDSCHs scheduled by the DCI of a PDCCH.

[0129] For example, when the PDSCH length is less than or equal to the threshold Th_p, there is only the first group of DMRS. When the PDSCH length is greater than the threshold Th_p, there is a second group of DMRS, whose symbol position is offset by X_p symbols relative to the first group of DMRS. Assume Th_p = 10 symbols. The base station schedules 4 PDSCHs through a DCI, each PDSCH having a length of 7 symbols, X_p = 8 symbols. Then, if the location of the additional DMRS is determined solely based on the time-domain information of each scheduled PDSCH, since the length of each PDSCH (7 symbols) is less than Th_p, then each PDSCH contains only the first group of DMRS, located in the first symbol of each PDSCH. If the location of the additional DMRS is determined jointly based on the time-domain information of all PDSCHs scheduled by the DCI of a PDCCH, since the total length of the 4 PDSCHs is 28 symbols, greater than Th_p, then within the 28 symbols of these 4 PDSCHs, the first symbol contains the first group of DMRS, and the ninth symbol contains the second group of DMRS. That is, PDSCH1 and PDSCH2 contain DMRS, while PDSCH3 and PDSCH4 do not contain DMRS.

[0130] Optionally, the duration of the time window is Y milliseconds, or Y time slots. Optionally, some DMRS patterns can be predefined.

[0131] Optionally, the correspondence between PDSCH types and DMRS patterns is predefined or configured by the base station. For example, the DMRS patterns corresponding to multiple PDSCHs scheduled by the DCI of a PDCCH are predefined or configured by the base station when configuring multi-PDSCH scheduling.

[0132] Optionally, the base station indicates a DMRS pattern from the DMRS pattern set via DCI.

[0133] Optionally, the base station indicates the quasi-located information (QCL) or precoding information of the DMRS and PDSCH. For example, if the DMRS pattern indicated by the base station is periodic, the base station can indicate that the DMRS within N time slots apart from the PDSCH uses the same precoding matrix as the PDSCH.

[0134] Figure 7 A simplified block diagram of entity 700 suitable for practicing various exemplary embodiments of this application is shown. Entity 700 can be configured as a network-side device, such as a base station, or it can be configured as a user-side device, such as a user terminal.

[0135] like Figure 7 As shown, entity 700 includes a processor 701, a memory 702 coupled to the processor 701, and a suitable radio frequency (RF) transmitter and receiver 704 coupled to the processor 701. The memory 702 stores a program 703. The transmitter / receiver 704 is suitable for bidirectional wireless communication. Note that the transmitter / receiver 704 has at least one antenna to assist communication; in practice, the base station or UE may have multiple antennas. Entity 700 can be coupled to one or more external networks or systems, such as the Internet, via a data path.

[0136] Program 703 may include program instructions that, when executed by the associated processor 701, cause entity 700 to operate in accordance with the exemplary embodiments of this application.

[0137] The embodiments of this application can be implemented by computer software executable by the processor 701 of entity 700, or by hardware, or by a combination of software and hardware.

[0138] Memory 702 can be any suitable type of memory appropriate to the local technical environment and can be implemented using any suitable data storage technology, such as semiconductor-based storage devices and systems, magnetic storage devices and systems, optical storage devices and systems, fixed memory, and removable memory, these are merely non-limiting examples. Although only one memory is shown in entity 700, multiple physically independent storage units may exist in entity 700. Processor 701 can be any suitable type of processor appropriate to the local technical environment and may include one or more of the following: general-purpose computer, special-purpose computer, microprocessor, digital signal processor (DSP), and processor based on a multi-core processor architecture, these are merely non-limiting examples.

[0139] When entity 700 is configured as a user-side device, that is, when entity 700 is a user equipment, in some embodiments, the receiver in transmitter / receiver 704 is configured to receive a PDCCH including DCI from the base station under the control of processor 701.

[0140] The receiver in transmitter / receiver 704 is also configured to receive, under the control of processor 701, a PDSCH scheduled by the PDCCH from the base station according to the DCI in the received PDCCH.

[0141] The transmitter in transmitter / receiver 704 is configured to send a HARQ-ACK / NACK codebook for PDSCH to the base station under the control of processor 701.

[0142] When entity 700 is configured as a network-side device, that is, when entity 700 is a base station, in some embodiments, the transmitter in transmitter / receiver 704 is configured to send a PDCCH including DCI to the terminal under the control of processor 701.

[0143] The transmitter in transmitter / receiver 704 is also configured to send PDSCH scheduled by PDCCH to the terminal.

[0144] The receiver in transmitter / receiver 704 is configured to receive HARQ-ACK / NACK codebook for PDSCH from the terminal under the control of processor 701.

[0145] It should be understood that the units included in entity 700 are configured to practice the exemplary embodiments disclosed herein. Therefore, the above in conjunction with Figure 1-6 The described operations and features also apply to entity 700 and its units, and their detailed descriptions are omitted here.

[0146] In another aspect, this application also provides a computer-readable storage medium, which may be the computer-readable storage medium included in the base station or communication device described in the above embodiments; or it may be a standalone computer-readable storage medium not assembled into a device. The computer-readable storage medium stores one or more programs, which are used by one or more processors to execute the communication methods described in this application.

[0147] The above description is merely a preferred embodiment of this application and an explanation of the technical principles employed. Those skilled in the art should understand that the scope of the invention involved in this application is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the inventive concept. For example, technical solutions formed by substituting the above features with (but not limited to) technical features with similar functions disclosed in this application.

Claims

1. A method performed by a terminal in a wireless communication network, comprising: The base station receives a first downlink control information (DCI) and a second DCI, wherein the first DCI is a first DCI format for scheduling a physical downlink shared channel (PDSCH) and the second DCI is a second DCI format for scheduling multiple PDSCHs. Determine a first HARQ-ACK subcodebook for the one PDSCH and a second HARQ-ACK subcodebook for the multiple PDSCHs; as well as Send a HARQ-ACK codebook, including a first HARQ-ACK sub-codebook and a second HARQ-ACK sub-codebook, to the base station.

2. The method according to claim 1, wherein, The first DCI format includes a first downlink allocation index (DAI), and the second DCI format includes a second DAI. The first DAI is applied to the first HARQ-ACK subcodebook, and the second DAI is applied to the second HARQ-ACK subcodebook.

3. The method according to claim 2, wherein, The second DAI indicates information about the first PDSCH among the plurality of PDSCHs, or indicates information about the last PDSCH among the plurality of PDSCHs.

4. The method according to claim 1, further comprising: The HARQ-ACK codebook is generated by appending the second HARQ-ACK subcodebook to the first HARQ-ACK subcodebook.

5. The method according to claim 2, wherein, Determining the first HARQ-ACK subcodebook for the one PDSCH and the second HARQ-ACK subcodebook for the plurality of PDSCHs includes: The first HARQ-ACK subcodebook is determined based on the number of HARQ-ACK bits corresponding to a PDSCH scheduled in the first DAI and the first DCI formats; and The second HARQ-ACK subcodebook is determined based on the number of HARQ-ACK bits corresponding to each PDSCH in the multiple PDSCHs scheduled by the second DAI and the second DCI formats.

6. The method according to claim 1, wherein, The second DCI format includes Zero Power Channel State Information Reference Signal (ZP CSI-RS) information. The rate matching of the plurality of PDSCHs is performed based on the ZP CSI-RS information.

7. The method according to claim 6, wherein, Rate matching of the plurality of PDSCHs based on ZP CSI-RS information includes at least one of the following: Each of the plurality of PDSCHs is rate-matched according to the ZP CSI-RS information; the PDSCH of each downlink time unit is rate-matched according to the ZP CSI-RS information; the first PDSCH is rate-matched according to the ZP CSI-RS information; the PDSCH in the first time unit that is scheduled is rate-matched according to the ZPCSI-RS information; and the PDSCHs that overlap with the ZP CSI-RS information are rate-matched according to the ZPCSI-RS information.

8. The method according to claim 1, wherein, Each of the first DCI format and the second DCI format includes control channel resource set (CORESET) information. The CORESET information in the second DCI format includes multiple CORESETs.

9. The method according to claim 1, wherein, Each of the first DCI format and the second DCI format includes information about HARQ-ACK timing.

10. The method according to claim 9, wherein, The second DCI format includes a HARQ-ACK timing information bit field, which is used to indicate the HARQ-ACK timing information of multiple PDSCHs scheduled by the second DCI format.

11. The method according to claim 10, wherein, The HARQ-ACK timing information bit field is used to determine the uplink time unit corresponding to the multiple PDSCHs.

12. The method according to claim 11, wherein, The timing information indicated by the HARQ-ACK timing information bit field is based on the last PDSCH among the plurality of PDSCHs.

13. The method according to claim 1, wherein, Information regarding the first DCI format and the second DCI format is configured by the base station, and the first DCI format or the second DCI format is predetermined.

14. A method performed by a base station in a wireless communication network, comprising: Send a first downlink control information (DCI) and a second DCI to the terminal, wherein the first DCI is a first DCI format for scheduling one physical downlink shared channel (PDSCH), and the second DCI is a second DCI format for scheduling multiple PDSCHs; and Receive from the terminal a HARQ-ACK codebook including a first HARQ-ACK sub-codebook and a second HARQ-ACK sub-codebook. The first HARQ-ACK subcodebook is associated with one PDSCH, and the second HARQ-ACK subcodebook is associated with the plurality of PDSCHs.

15. The method according to claim 14, wherein, The first DCI format includes a first downlink allocation index (DAI), and the second DCI format includes a second DAI. The first DAI is applied to the first HARQ-ACK subcodebook, and the second DAI is applied to the second HARQ-ACK subcodebook.

16. The method according to claim 15, wherein, The second DAI indicates information about the first PDSCH among the plurality of PDSCHs, or indicates information about the last PDSCH among the plurality of PDSCHs.

17. The method of claim 14, wherein, The HARQ-ACK codebook is generated by appending the second HARQ-ACK sub-codebook to the first HARQ-ACK sub-codebook.

18. The method according to claim 15, wherein, The number of HARQ-ACK bits corresponding to one PDSCH in the first DAI and the first DCI format scheduling is determined by the number of bits. The second HARQ-ACK subcodebook is determined based on the number of HARQ-ACK bits corresponding to each PDSCH in the multiple PDSCHs scheduled by the second DAI and the second DCI formats.

19. The method according to claim 14, wherein, The second DCI format includes Zero Power Channel State Information Reference Signal (ZP CSI-RS) information. The rate matching of the plurality of PDSCHs is performed based on the ZP CSI-RS information.

20. The method according to claim 19, wherein, Rate matching of the plurality of PDSCHs based on ZP CSI-RS information includes at least one of the following: Each of the plurality of PDSCHs is rate-matched according to the ZP CSI-RS information; the PDSCH of each downlink time unit is rate-matched according to the ZP CSI-RS information; the first PDSCH is rate-matched according to the ZP CSI-RS information; the PDSCH in the first time unit that is scheduled is rate-matched according to the ZPCSI-RS information; and the PDSCHs that overlap with the ZP CSI-RS information are rate-matched according to the ZPCSI-RS information.

21. The method according to claim 14, wherein, Each of the first DCI format and the second DCI format includes control channel resource set (CORESET) information. The CORESET information in the second DCI format includes multiple CORESETs.

22. The method according to claim 14, wherein, Each of the first DCI format and the second DCI format includes information about HARQ-ACK timing.

23. The method according to claim 22, wherein, The second DCI format includes a HARQ-ACK timing information bit field, which is used to indicate the HARQ-ACK timing information of multiple PDSCHs scheduled by the second DCI format.

24. The method according to claim 23, wherein, The HARQ-ACK timing information bit field is used to determine the uplink time unit corresponding to the multiple PDSCHs.

25. The method according to claim 24, wherein, The timing information indicated by the HARQ-ACK timing information bit field is based on the last PDSCH among the plurality of PDSCHs.

26. The method according to claim 14, wherein, The information regarding the first DCI format and the second DCI format is configured by the base station, and The first DCI format or the second DCI format is predetermined.

27. A terminal in a wireless communication network, comprising: transceiver; and A processor coupled to the transceiver and configured to control the transceiver to perform the method according to any one of claims 1 to 13.

28. A base station in a wireless communication network, comprising: transceiver; and A processor coupled to the transceiver and configured to control the transceiver to perform the method according to any one of claims 14 to 26.

29. A computer-readable storage medium storing computer instructions that, when executed by a processor, enable the processor to perform the method as described in any one of claims 1 to 26.

Images