Search

EP-4104340-B1 - A METHOD AND APPARATUS FOR HARQ-ACK CODEBOOK DETERMINATION FOR FRAME-BASED EQUIPMENT OPERATION

EP4104340B1EP 4104340 B1EP4104340 B1EP 4104340B1EP-4104340-B1

Inventors

  • LEI, HAIPENG
  • ZHANG, YU

Dates

Publication Date
20260506
Application Date
20200214

Claims (14)

  1. A method for wireless communication performed by a user equipment, UE, the method comprising: receiving first downlink control information, DCI, for scheduling a first data transmission in a first fixed frame period, FFP; receiving second DCI for scheduling a second data transmission in a second fixed frame period which is later than the first fixed frame period; determining whether there is hybrid automatic repeat request acknowledgement, HARQ-ACK, feedback corresponding to the first data transmission postponed in the first fixed frame period; and transmitting a HARQ-ACK codebook in the second fixed frame period, wherein, in response to determining that there is the HARQ-ACK feedback corresponding to the first data transmission postponed in the first fixed frame period, the HARQ-ACK codebook comprises HARQ-ACK feedback corresponding to the second data transmission and the HARQ-ACK feedback corresponding to the first data transmission; wherein determining whether there is HARQ-ACK feedback corresponding to the first data transmission postponed in the first fixed frame period comprises receiving indications of downlink association sets which respectively cover intra-FFP HARQ-ACK feedback and cross-FFP HARQ-ACK feedback, where: the HARQ-ACK feedback corresponding to the first data transmission is not counted in the postponed HARQ-ACK feedback in response to receiving a first downlink association set which covers intra-FFP HARQ-ACK feedback for the first data transmission; and the HARQ-ACK feedback corresponding to the first data transmission is counted in the postponed HARQ-ACK feedback in response to receiving a second downlink association set which covers cross-FFP HARQ-ACK feedback for the first data transmission; where the first DCI including a first indicator indicating that HARQ-ACK feedback corresponding to the first data transmission is postponed is a downlink association set which covers cross-FFP HARQ-ACK feedback for the first data transmission, and the second DCI includes a second indicator indicating that HARQ-ACK feedback corresponding to the first data transmission is postponed which is a downlink association set which covers cross-FFP HARQ ACK feedback for the first data transmission.
  2. The method of claim 1, wherein the second DCI includes a second indicator indicating a set of HARQ feedback timing offset values and determining whether there is the HARQ-ACK feedback corresponding to the first data transmission postponed in the first fixed frame period comprises: determining, based on the set of HARQ feedback timing offset values, whether there is at least one slot in the first fixed frame period included in a downlink association set associated with the HARQ-ACK codebook.
  3. The method of claim 1, wherein a maximum number of candidate PDSCH transmissions with corresponding HARQ-ACK feedback postponed in the first fixed frame period is determined based on processing capability of the UE, and optionally wherein the HARQ-ACK feedback corresponding to the maximum number of candidate PDSCH transmissions is included in the HARQ-ACK codebook.
  4. Apparatus for wireless communication, the apparatus comprising at least one processor coupled with at least one memory and configured to cause the apparatus to: receive first downlink control information, DCI, for scheduling a first data transmission in a first fixed frame period, FFP; receive second DCI for scheduling a second data transmission in a second fixed frame period which is later than the first fixed frame period; determine whether there is hybrid automatic repeat request acknowledgement, HARQ-ACK, feedback corresponding to the first data transmission postponed in the first fixed frame period; and transmit a HARQ-ACK codebook in the second fixed frame period, wherein, in response to determining that there is the HARQ-ACK feedback corresponding to the first data transmission postponed in the first fixed frame period, the HARQ-ACK codebook comprises HARQ-ACK feedback corresponding to the second data transmission and the HARQ-ACK feedback corresponding to the first data transmission; wherein determining whether there is HARQ-ACK feedback corresponding to the first data transmission postponed in the first fixed frame period comprises receiving indications of downlink association sets which respectively cover intra-FFP HARQ-ACK feedback and cross-FFP HARQ-ACK feedback, where: the HARQ-ACK feedback corresponding to the first data transmission is not counted in the postponed HARQ-ACK feedback in response to receiving a first downlink association set which covers intra-FFP HARQ-ACK feedback for the first data transmission; and the HARQ-ACK feedback corresponding to the first data transmission is counted in the postponed HARQ-ACK feedback in response to receiving a second downlink association set which covers cross-FFP HARQ-ACK feedback for the first data transmission; where the first DCI including a first indicator indicating that HARQ-ACK feedback corresponding to the first data transmission is postponed is a downlink association set which covers cross-FFP HARQ-ACK feedback for the first data transmission, and the second DCI includes a second indicator indicating that HARQ-ACK feedback corresponding to the first data transmission is postponed which is a downlink association set which covers cross-FFP HARQ ACK feedback for the first data transmission.
  5. A method for wireless communication performed by a base station, BS, the method comprising: transmitting, to a UE first DCI for scheduling a first data transmission in a first fixed frame period, FFP, wherein the first DCI includes a first indicator indicating that HARQ-ACK feedback corresponding to the first data transmission is postponed; transmitting, to the UE, second DCI for scheduling a second data transmission in a second fixed frame period which is later than the first fixed frame period; and receiving, from the UE, a HARQ-ACK codebook in the second fixed frame period, wherein the HARQ-ACK codebook comprises HARQ-ACK feedback corresponding to the second data transmission and the HARQ-ACK feedback corresponding to the first data transmission; wherein the BS transmits indications of downlink association sets which respectively cover intra-FFP HARQ-ACK feedback and cross-FFP HARQ-ACK feedback; where the first DCI including a first indicator indicating that HARQ-ACK feedback corresponding to the first data transmission is postponed is a downlink association set which covers cross-FFP HARQ-ACK feedback for the first data transmission, and the second DCI includes a second indicator indicating that HARQ-ACK feedback corresponding to the first data transmission is postponed which is a downlink association set which covers cross-FFP HARQ-ACK feedback for the first data transmission.
  6. Apparatus for wireless communication, the apparatus comprising at least one memory and at least one processor coupled with the at least one memory and configured to cause the apparatus to: transmit, to a UE, first DCI for scheduling a first data transmission in a first fixed frame period, FFP, wherein the first DCI includes a first indicator indicating that HARQ-ACK feedback corresponding to the first data transmission is postponed; transmit, to the UE, second DCI for scheduling a second data transmission in a second fixed frame period which is later than the first fixed frame period; and receive, from the UE, a HARQ-ACK codebook in the second fixed frame period, wherein the HARQ-ACK codebook comprises HARQ-ACK feedback corresponding to the second data transmission and the HARQ-ACK feedback corresponding to the first data transmission; wherein the BS transmits indications of downlink association sets which respectively cover intra-FFP HARQ-ACK feedback and cross-FFP HARQ-ACK feedback; where the first DCI including a first indicator indicating that HARQ-ACK feedback corresponding to the first data transmission is postponed is a downlink association set which covers cross-FFP HARQ-ACK feedback for the first data transmission, and the second DCI includes a second indicator indicating that HARQ-ACK feedback corresponding to the first data transmission is postponed which is a downlink association set which covers cross-FFP HARQ-ACK feedback for the first data transmission.
  7. Apparatus according to claim 6, wherein the second DCI includes a second indicator indicating a set of HARQ feedback timing offset values, whereby the UE determines whether there is the HARQ-ACK feedback corresponding to the first data transmission postponed in the first fixed frame period by: determining, based on the set of HARQ feedback timing offset values, whether there is at least one slot in the first fixed frame period included in the downlink association set associated with the HARQ-ACK codebook.
  8. Apparatus according to claim 6, wherein the second DCI includes a second indicator indicating a set of HARQ feedback timing offset values from a plurality of sets of HARQ feedback timing offset values.
  9. Apparatus according to claim 8, wherein the plurality of sets of HARQ feedback timing offset values are configured by radio resource control (RRC) signaling and the plurality of sets of HARQ feedback timing offset values include at least one set of HARQ-ACK feedback timing offset values, and the at least one set of HARQ-ACK feedback timing offset values corresponds to a downlink association set including one or more slots in the first fixed frame period.
  10. Apparatus according to claim 6, wherein the second DCI includes the second indicator indicating an existence of the HARQ-ACK feedback postponed in the first fixed frame period, whereby the UE determines whether there is the HARQ-ACK feedback corresponding to the first data transmission postponed in the first fixed frame period.
  11. Apparatus according to claim 10, wherein the HARQ-ACK feedback postponed in the first fixed frame period are bundled to one bit by performing logic AND operation, and the one bit is included in the HARQ-ACK codebook.
  12. Apparatus according to claim 10, wherein a total number of HARQ-ACK information bits for the HARQ-ACK feedback postponed in the first fixed frame period is configured by RRC signaling, and the total number of HARQ-ACK information bits is included in the HARQ-ACK codebook.
  13. Apparatus according to claim 6, wherein the second DCI includes a second indicator indicating a total number of one or more physical downlink shared channel (PDSCH) transmissions with corresponding HARQ-ACK feedback postponed in the first fixed frame period.
  14. Apparatus according to claim 6, wherein the second DCI includes a second indicator indicating a total number of HARQ-ACK information bits for the HARQ-ACK feedback postponed in the first fixed frame period.

Description

TECHNICAL FIELD Embodiments of the present disclosure generally relate to wireless communication technology, especially to technology for hybrid automatic repeat request acknowledgement (HARQ-ACK) transmission on unlicensed spectrum under 3GPP (3rd Generation Partnership Project) 5G new radio (NR). BACKGROUND During 3GPP Release 13 Long Term Evolution (LTE) Licensed Assisted Access (LAA) study item phase, frame based equipment (FBE) based channel access mechanism is not accepted, while load based equipment (LBE) based channel access mechanism is specified according to wireless fidelity (WiFi) channel access mechanism. In 3GPP Release 16 the new radio (NR) access on unlicensed spectrum (NR-U), more use cases are targeted. Therefore, FBE based channel access mechanism, which has more benefits compared with LBE based channel access mechanism, has been adopted in 3GPP Release 16 NR-U. Currently, details regarding determining a HARQ-ACK codebook for a FBE based channel access mechanism have not been discussed in 3GPP 5G NR technology yet. VIVO, "Discussion on HARQ operation for NR-U", 3GPP DRAFT; R1-1904067, 7 April 2019, vol. RAN WG1, Meeting #96 bis, Xi'an, China; 3RD GENERATION PARTNERSHIP PROJECT (3GPP), includes various proposals relating to inter alia HARQ feedback timing in the case of NR-U operation. WO2019095314A1 discloses a system and method for codebook feedback for data retransmissions. SUMMARY The invention is defined by the appended independent claims. BRIEF DESCRIPTION OF THE DRAWINGS In order to describe the manner in which advantages and features of the application can be obtained, a description of the application is rendered by reference to specific embodiments thereof, which are illustrated in the appended drawings. These drawings depict only example embodiments of the application and are not therefore to be considered limiting of its scope. FIG. 1 illustrates a schematic diagram of a wireless communication system 100 in accordance with some embodiments of the present application;FIG. 2 illustrates an exemplary fixed frame period (FFP) data structure for an FBE in accordance with some embodiments of the present application;FIG. 3 illustrates an exemplary diagram of intra-FFP scheduling and HARQ-ACK feedback in accordance with some embodiments of the present application;FIG. 4 illustrates a flow chart of a method for wireless communications in accordance with some embodiments of the present application;FIG. 5 illustrates an exemplary diagram of retransmitting postponed HARQ-ACK feedback in accordance with some embodiments of the present application;FIG. 6 illustrates a further exemplary diagram of retransmitting postponed HARQ-ACK feedback in accordance with some embodiments of the present application;FIG. 7 illustrates another exemplary diagram of retransmitting postponed HARQ-ACK feedback in accordance with some embodiments of the present application;FIG. 8 illustrates an additional exemplary diagram of retransmitting postponed HARQ-ACK feedback in accordance with some embodiments of the present application;FIG. 9 illustrates another flow chart of a method for wireless communications in accordance with some embodiments of the present application; andFIG. 10 illustrates a block diagram of an exemplary apparatus in accordance with some embodiments of the present application. DETAILED DESCRIPTION The detailed description of the appended drawings is intended as a description of preferred embodiments of the present disclosure, and is not intended to represent the only form in which the present disclosure may be practiced. The scope of protection is defined by the claims. Reference will now be made in detail to some embodiments of the present disclosure, examples of which are illustrated in the accompanying drawings. To facilitate understanding, embodiments are provided under specific network architecture and new service scenarios, such as 3GPP 5G, 3GPP LTE Release 8 and so on. Persons skilled in the art know very well that, with the development of network architecture and new service scenarios, the embodiments in the present disclosure are also applicable to similar technical problems. FIG. 1 illustrates a schematic diagram of a wireless communication system 100 in accordance with some embodiments of the present application. As shown in FIG. 1, the wireless communication system 100 includes at least one user equipment (UE) 101 and at least one base station (BS) 102. In particular, the wireless communication system 100 includes two UEs 101, e.g., UE 101a and UE 101b, and two BSs 102, e.g., BS 102a and BS 102b for illustrative purpose. Although a specific number of UEs 101 and BS 102 are depicted in FIG. 1, it is contemplated that any number of UEs 101 and BSs 102 may be included in the wireless communication system 100. The UE(s) 101 may include computing devices, such as desktop computers, laptop computers, personal digital assistants (PDAs), tablet computers, smart televisions (e.g., televisions