WO2022011674A1

WO2022011674A1 - Method, device and computer storage medium for communication

Info

Publication number: WO2022011674A1
Application number: PCT/CN2020/102646
Authority: WO
Inventors: Yukai GAO; Gang Wang
Original assignee: NEC Corp
Current assignee: NEC Corp
Priority date: 2020-07-17
Filing date: 2020-07-17
Publication date: 2022-01-20
Anticipated expiration: 2023-01-17

Abstract

Embodiments of the present disclosure relate to methods, devices and computer storage media for communication. A method comprises transmitting, from a network device to a terminal device, a first physical downlink shared channel (PDSCH) repetition in a first sub-slot and a second PDSCH repetition in a second sub-slot. The method further comprises receiving a hybrid automatic repeat request acknowledgement (HARQ-ACK) message from the terminal device in a third sub-slot, where the third sub-slot is determined based on a sub-slot offset for HARQ-ACK feedback and one of the first and second sub-slots. As such, embodiments of the present disclosure can support sub-slot based HARQ-ACK feedback.

Description

METHOD, DEVICE AND COMPUTER STORAGE MEDIUM FOR COMMUNICATION

TECHNICAL FIELD

Embodiments of the present disclosure generally relate to the field of telecommunication, and in particular, to methods, devices and computer storage media for communication.

BACKGROUND

In the latest 3GPP specification (that is, Release 16) , an intra-slot repetition scheme (that is, Scheme 3) for multi-transmission and reception point (multi-TRP) transmission is agreed. That is, there may be more than one physical downlink shared channel (PDSCH) transmission occasions in one slot. In order to reduce feedback latency, it is desired to support sub-slot based hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback. However, in Release 16, semi-static HARQ-ACK codebook (that is, Type-1 HARQ-ACK codebook) only supports slot based HARQ-ACK feedback, without supporting sub-slot based HARQ-ACK feedback.

SUMMARY

In general, example embodiments of the present disclosure provide methods, devices and computer storage media for HARQ-ACK feedback.

In a first aspect, there is provided a method of communication. The method comprises transmitting, from a network device to a terminal device, a first PDSCH repetition in a first sub-slot and a second PDSCH repetition in a second sub-slot; and receiving a HARQ-ACK message from the terminal device in a third sub-slot, wherein the third sub-slot is determined based on a sub-slot offset for HARQ-ACK feedback and one of the first and second sub-slots.

In a second aspect, there is provided a method of communication. The method comprises receiving, at a terminal device and from a network device, a first PDSCH repetition in a first sub-slot and a second PDSCH repetition in a second sub-slot; generating a HARQ-ACK message by decoding at least one of the first and second PDSCH repetitions; and transmitting the HARQ-ACK message to the network device in a third sub-slot, wherein the third sub-slot is determined based on a sub-slot offset for HARQ-ACK feedback and one of the first and second sub-slots.

In a third aspect, there is provided a network device. The network device comprises a processor and a memory coupled to the processor. The memory stores instructions that when executed by the processor, cause the network device to perform actions. The actions comprise transmitting, to a terminal device, a first PDSCH repetition in a first sub-slot and a second PDSCH repetition in a second sub-slot; and receiving a HARQ-ACK message from the terminal device in a third sub-slot, wherein the third sub-slot is determined based on a sub-slot offset for HARQ-ACK feedback and one of the first and second sub-slots.

In a fourth aspect, there is provided a terminal device. The terminal device comprises a processor and a memory coupled to the processor. The memory stores instructions that when executed by the processor, cause the terminal device to perform actions. The actions comprise receiving, from a network device, a first PDSCH repetition in a first sub-slot and a second PDSCH repetition in a second sub-slot; generating a HARQ-ACK message by decoding at least one of the first and second PDSCH repetitions; and transmitting the HARQ-ACK message to the network device in a third sub-slot, wherein the third sub-slot is determined based on a sub-slot offset for HARQ-ACK feedback and one of the first and second sub-slots.

In a fifth aspect, there is provided a computer readable medium having instructions stored thereon. The instructions, when executed on at least one processor, cause the at least one processor to perform the method according to the above first or second aspect.

In a sixth aspect, there is provided a computer program product that is stored on a computer readable medium and includes machine-executable instructions. The machine-executable instructions, when being executed, cause a machine to perform the method according to the above first or second aspect.

It is to be understood that the summary section is not intended to identify key or essential features of embodiments of the present disclosure, nor is it intended to be used to limit the scope of the present disclosure. Other features of the present disclosure will become easily comprehensible through the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

Through the more detailed description of some embodiments of the present disclosure in the accompanying drawings, the above and other objects, features and advantages of the present disclosure will become more apparent, wherein:

FIG. 1 illustrate an example communication network in which embodiments of the present disclosure can be implemented;

FIG. 2 illustrates a signaling chart for HARQ-ACK feedback in accordance with some embodiments of the present disclosure;

FIG. 3A illustrates an example of HARQ-ACK feedback in accordance with some embodiments of the present disclosure;

FIG. 3B illustrates an example of HARQ-ACK feedback in accordance with some embodiments of the present disclosure;

FIG. 4 illustrates an example of HARQ-ACK feedback in accordance with some embodiments of the present disclosure;

FIG. 5 illustrates an example TDRA table in accordance with some embodiments of the present disclosure;

FIG. 6 illustrates an example TDRA table in accordance with some embodiments of the present disclosure;

FIG. 7 illustrates a flowchart of an example method in accordance with some embodiments of the present disclosure;

FIG. 8 illustrates a flowchart of an example method in accordance with some embodiments of the present disclosure; and

FIG. 9 is a simplified block diagram of a device that is suitable for implementing embodiments of the present disclosure.

Throughout the drawings, the same or similar reference numerals represent the same or similar element.

DETAILED DESCRIPTION

Principle of the present disclosure will now be described with reference to some example embodiments. It is to be understood that these embodiments are described only for the purpose of illustration and help those skilled in the art to understand and implement the present disclosure, without suggesting any limitations as to the scope of the disclosure. The disclosure described herein can be implemented in various manners other than the ones described below.

In the following description and claims, unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skills in the art to which this disclosure belongs.

As used herein, the singular forms ‘a’ , ‘an’ and ‘the’ are intended to include the plural forms as well, unless the context clearly indicates otherwise. The term ‘includes’ and its variants are to be read as open terms that mean ‘includes, but is not limited to. ’ The term ‘based on’ is to be read as ‘at least in part based on. ’ The term ‘some embodiments’ and ‘an embodiment’ are to be read as ‘at least some embodiments. ’ The term ‘another embodiment’ is to be read as ‘at least one other embodiment. ’ The terms ‘first, ’ ‘second, ’ and the like may refer to different or same objects. Other definitions, explicit and implicit, may be included below.

In some examples, values, procedures, or apparatus are referred to as ‘best, ’ ‘lowest, ’ ‘highest, ’ ‘minimum, ’ ‘maximum, ’ or the like. It will be appreciated that such descriptions are intended to indicate that a selection among many used functional alternatives can be made, and such selections need not be better, smaller, higher, or otherwise preferable to other selections.

In Release 16, an intra-slot repetition scheme (that is, Scheme 3) for multi-TRP transmission is agreed. That is, there may be more than one PDSCH transmission occasions in one slot. In order to reduce feedback latency, it is desired to support sub-slot based HARQ-ACK feedback. However, in Release 16, semi-static HARQ-ACK codebook (that is, Type-1 HARQ-ACK codebook) only supports slot based HARQ-ACK feedback, without supporting sub-slot based HARQ-ACK feedback.

Traditionally, if a terminal device (for example, UE) receives a PDSCH transmission from a network device, the UE may report corresponding HARQ-ACK information in a PUCCH to the network device. The terminal device may report the HARQ-ACK information based on the HARQ-ACK timing indicated by radio resource control (RRC) signaling or downlink control information (DCI) . If it is indicated to report HARQ-ACK information for multiple PDSCHs in a same slot, the HARQ-ACK bits for the multiple PDSCHs are constructed in a HARQ-ACK codebook.

Traditionally, the Type-1 HARQ-ACK codebook is determined based on the following factors: (1) PDSCH-to-HARQ_feedback timing values K1; (2) PDSCH time domain resource allocation (TDRA) table; (3) the ratio

between the downlink subcarrier spacing (SCS) configuration μ _DL and the uplink SCS configuration μ _UL if different numerology between downlink (DL) and uplink (UL) is configured; and (3) time division duplex (TDD) configuration. For example, the UE may determine the HARQ-ACK window size based on the HARQ-ACK timing values K1, for example, {5, 6, 7} . For each K1, the UE may determine the candidate PDSCH reception occasions in each slot based on a time domain resource allocation (TDRA) table and TDD configuration. In particular, candidate PDSCH reception occasions in the TDRA table overlapping with UL configured by TDD-UL-DL-ConfigurationCommon and TDD-UL-DL-ConfigDedicated are excluded. For the overlapping candidate PDSCH reception occasions, only one HARQ-ACK position (for example, one or two HARQ-ACK bits) can be generated.

As described above, if the intra-slot repetition scheme (that is, Scheme 3) is configured, there may be more than one PDSCH transmission occasions (also referred to as “PDSCH repetitions” in the following) in one slot, for example, a first PDSCH transmission occasion and a second PDSCH transmission occasion. In the current specification, a start and length indicator value (SLIV) comprised in the TDRA table is only configured for the first PDSCH transmission occasion, which indicates time domain resources allocated for the first PDSCH transmission occasion. A HARQ-ACK position in the HARQ-ACK codebook can be determined for the first PDSCH transmission occasion based on the SLIV. However, no SLIV is configured for the second PDSCH transmission occasion. The time domain resources for the second PDSCH transmission occasion can be determined based on the time domain resources for the first PDSCH transmission occasion and a symbol offset, where the number of symbols for the second PDSCH transmission occasion is the same as the number of symbols for the first PDSCH transmission occasion. Since no SLIV for the second PDSCH transmission occasion is available in the TDRA table, no HARQ-ACK position in the HARQ-ACK codebook can be determined based on the second PDSCH transmission occasion. That is, in this case, the UE is unable to report HARQ-ACK information based on the second PDSCH transmission occasion.

Embodiments of the present disclosure provide a solution for HARQ-ACK feedback, so as to solve the above problems and one or more of other potential problems. According to this solution, a first PDSCH repetition is transmitted from a network device to a terminal device in a first sub-slot and a second PDSCH repetition is transmitted from the network device to the terminal device in a second sub-slot. The terminal device generates a HARQ-ACK message by decoding at least one of the first and second PDSCH repetitions. The HARQ-ACK message is transmitted from the terminal device to the network device in a third sub-slot determined based on a sub-slot offset for HARQ-ACK feedback and one of the first and second sub-slots. As such, embodiments of the present disclosure can support sub-slot based HARQ-ACK feedback. Moreover, no matter whether the third sub-slot is determined based on the first sub-slot or the second sub-slot, a HARQ-ACK position for the PDSCH can always be found in the HARQ-ACK codebook.

Principle and implementations of the present disclosure will be described in detail below with reference to FIG. 1-9.

In the following, the terms “transmission occasion” , “transmission” , “repetition” , “reception” , “reception occasion” , “PDSCH transmission occasion” , “PDSCH transmission” , “PDSCH reception occasion” , “PDSCH reception” and “PDSCH repetition” can be used interchangeably. The terms “position of the feedback” , “HARQ-ACK information location” , “HARQ-ACK position” , “HARQ-ACK location” , “HARQ position” , “HARQ location” , “feedback position” and “feedback location” can be used interchangeably. The terms “HARQ-ACK information” , “HARQ-ACK message” , “HARQ message” , “HARQ information” , “feedback message” and “feedback information” can be used interchangeably.

FIG. 1 shows an example communication network 100 in which implementations of the present disclosure can be implemented. The network 100 includes a network device 110 and a terminal device 120 served by the network device 110. The network 100 can provide at least one serving cell 102 to serve the terminal device 120. It is to be understood that the number of network devices, terminal devices and/or serving cells is only for the purpose of illustration without suggesting any limitations. The network 100 may include any suitable number of network devices, terminal devices and/or serving cells adapted for implementing implementations of the present disclosure.

As used herein, the term “terminal device” refers to any device having wireless or wired communication capabilities. Examples of the terminal device include, but not limited to, user equipment (UE) , personal computers, desktops, mobile phones, cellular phones, smart phones, personal digital assistants (PDAs) , portable computers, tablets, wearable devices, internet of things (IoT) devices, Internet of Everything (IoE) devices, machine type communication (MTC) devices, device on vehicle for V2X communication where X means pedestrian, vehicle, or infrastructure/network, or image capture devices such as digital cameras, gaming devices, music storage and playback appliances, or Internet appliances enabling wireless or wired Internet access and browsing and the like. For the purpose of discussion, in the following, some embodiments will be described with reference to UE as an example of the terminal device 120.

As used herein, the term ‘network device’ or ‘base station’ (BS) refers to a device which is capable of providing or hosting a cell or coverage where terminal devices can communicate. Examples of a network device include, but not limited to, a Node B (NodeB or NB) , an Evolved NodeB (eNodeB or eNB) , a next generation NodeB (gNB) , a Transmission Reception Point (TRP) , a Remote Radio Unit (RRU) , a radio head (RH) , a remote radio head (RRH) , a low power node such as a femto node, a pico node, and the like.

In one embodiment, the terminal device 120 may be connected with a first network device and a second network device (not shown in FIG. 1) . One of the first network device and the second network device may be in a master node and the other one may be in a secondary node. The first network device and the second network device may use different radio access technologies (RATs) . In one embodiment, the first network device may be a first RAT device and the second network device may be a second RAT device. In one embodiment, the first RAT device may be an eNB and the second RAT device is a gNB. Information related to different RATs may be transmitted to the terminal device 120 from at least one of the first network device and the second network device. In one embodiment, first information may be transmitted to the terminal device 120 from the first network device and second information may be transmitted to the terminal device 120 from the second network device directly or via the first network device. In one embodiment, information related to configuration for the terminal device configured by the second network device may be transmitted from the second network device via the first network device. Information related to reconfiguration for the terminal device configured by the second network device may be transmitted to the terminal device from the second network device directly or via the first network device. The information may be transmitted via any of the following: Radio Resource Control (RRC) signaling, Medium Access Control (MAC) control element (CE) or Downlink Control Information (DCI) .

In the communication network 100, the network device 110 can communicate data and control information to the terminal device 120 and the terminal device 120 can also communication data and control information to the network device 110. A link from the network device 110 to the terminal device 120 is referred to as a downlink (DL) , while a link from the terminal device 120 to the network device 110 is referred to as an uplink (UL) .

The communications in the network 100 may conform to any suitable standards including, but not limited to, Global System for Mobile Communications (GSM) , Long Term Evolution (LTE) , LTE-Evolution, LTE-Advanced (LTE-A) , Wideband Code Division Multiple Access (WCDMA) , Code Division Multiple Access (CDMA) , GSM EDGE Radio Access Network (GERAN) , Machine Type Communication (MTC) and the like. Furthermore, the communications may be performed according to any generation communication protocols either currently known or to be developed in the future. Examples of the communication protocols include, but not limited to, the first generation (1G) , the second generation (2G) , 2.5G, 2.75G, the third generation (3G) , the fourth generation (4G) , 4.5G, the fifth generation (5G) communication protocols.

FIG. 2 shows a signaling chart illustrating a process 200 for HARQ-ACK feedback according to some implementations of the present disclosure. For the purpose of discussion, the process 200 will be described with reference to Fig. 1. The process 200 may involve the network device 110 and the terminal device 120 as shown in Fig. 1.

In some embodiments, the terminal device 120 may be configured with sub-slot based HARQ-ACK feedback. In some embodiments, a sub-slot length may be configured to the terminal device 120 via any of RRC, MAC CE and DCI, which indicates the number of symbols included in one sub-slot. For example, the sub-slot length may be any one of 2 symbols, 7 symbols or 14 symbols.

As shown in FIG. 2, in some embodiments, if the intra-slot repetition scheme (for example, TDMSchemeA) is configured, and/or if two TCI states are indicated by the DCI field ‘Transmission Configuration Indicator’ , the network device 110 may transmit 210, to the terminal device 120, a first PDSCH repetition (also referred to as “first PDSCH transmission” or “first PDSCH transmission occasion” ) in a first sub-slot and a second PDSCH repetition (also referred to as “second PDSCH transmission” or “second PDSCH transmission occasion” ) in a second sub-slot. The terminal device 120 may decode at least one of the first and second PDSCH repetitions and generate 220 a HARQ-ACK message (also referred to as “HARQ-ACK information” ) based on a result of the decoding. For example, if any one of the first PDSCH repetition, the second PDSCH repetition or a soft combination of the first and second PDSCH repetitions is decoded by the terminal device 120 successfully, the terminal device 120 may provide the HARQ-ACK message indicating an acknowledgement (ACK) to the network device 110. If none of the first PDSCH repetition, the second PDSCH repetition and a soft combination of the first and second PDSCH repetitions is decoded by the terminal device 120 successfully, the terminal device 120 may provide the HARQ-ACK message indicating a negative acknowledgement (NACK) to the network device 110. The network device 110 may receive 230 the HARQ-ACK message or the HARQ-ACK information in a third sub-slot, where the third sub-slot may be determined based on a sub-slot offset for HARQ-ACK feedback and one of the first and second sub-slots.

In some embodiments, a TDRA table comprising a plurality of SLIVs may be configured by the network device 110 to the terminal device, for example, via RRC signaling or via a predefined Table (such as, Table 5.1.2.1.1-1, Table 5.1.2.1.1-2, Table 5.1.2.1.1-3, Table 5.1.2.1.1-4 and/or Table 5.1.2.1.1-5 in the 3GPP specification TS 38.214) . A SLIV (also referred to as “first SLIV” ) comprised in the plurality of SLIVs may be configured for the first PDSCH transmission and indicated by the network device 110 to the terminal device (for example, via DCI) . The first SLIV configured for the first PDSCH transmission may indicate time domain resources allocated for the first PDSCH transmission. For example, the first sub-slot may be determined based on the SLIV configured for the first PDSCH transmission. In some embodiments, a symbol offset between the first PDSCH transmission and the second PDSCH transmission may be configured by the network device 110 to the terminal device via RRC signaling. The time domain resources for the second PDSCH transmission may be determined based on the time domain resources for the first PDSCH transmission and the symbol offset, where the number of symbols (also referred to as “symbol length” in the following) for the second PDSCH transmission is the same as the number of symbols for the first PDSCH transmission. For example, the second sub-slot can be determined based on the time domain resources allocated for the second PDSCH transmission. For example, if the first SLIV indicates a starting symbol index S (where S is an integer and 0 ≤ S ≤ 12) and a symbol length L (where L is an integer and 2 ≤ L ≤ 14) used for the first PDSCH transmission occasion and if the symbol offset between the first PDSCH transmission occasion and the second PDSCH transmission occasion is X (where X is an integer and 0 ≤X ≤ 7; for example, X is configured by the parameter startingSymbolOffsetK) , a virtual SLIV (also referred to as “third SLIV” ) for the second PDSCH transmission may indicate a starting symbol index S+L+X and a symbol length L used for the second PDSCH transmission. In some embodiments, a sub-slot offset k for HARQ-ACK feedback may be configured by the network device 110 to the terminal device 120 via any of RRC signaling, MAC CE and DCI, where k is an integer. For example, 0 ≤ k ≤ 32. For another example, 0 ≤ k ≤ 224. For another example, 0 ≤ k ≤ 256. The third sub-slot for HARQ-ACK feedback can be determined based on the sub-slot offset k and one of the first and second sub-slots.

In some embodiments, if sub-slot based Type-1 HARQ-ACK feedback is configured, the third sub-slot may be determined based on the sub-slot offset k and the first sub-slot including the first PDSCH transmission. For example, if the first PDSCH transmission occurs in sub-slot m (that is, the first sub-slot) and the second PDSCH transmission occurs in sub-slot m+p (that is, the second sub-slot) , for example, p is an integer and 0 ≤ p ≤ 7 or 1 ≤ p ≤ 6 (such as, p = 1) , the HARQ-ACK feedback may occur in sub-slot m+k (that is, the third sub-slot) . In some embodiments, the third sub-slot for HARQ-ACK feedback may be determined based on the sub-slot offset k and the first sub-slot, if the first sub-slot for the first PDSCH transmission and the second sub-slot for the second PDSCH transmission are different sub-slots in one slot and/or if there is no SLIV in the TDRA table locating or starting or ending in the second sub-slot and overlapping with the second PDSCH transmission.

In some embodiments, in order to ensure enough PDSCH processing time, a time offset between a last symbol of any of the first and second PDSCH transmissions and a start symbol of a PUCCH carrying the HARQ-ACK message should be greater than or equal to PDSCH processing time.

In some embodiments, if a time offset between the last symbol of the last PDSCH transmission occasion (for example, the second PDSCH transmission occasion) and the start symbol of the PUCCH carrying the HARQ-ACK message is greater than or equal to the PDSCH processing time, the terminal device 120 may provide a valid HARQ-ACK message to the network device 110. For example, if the time offset between the last symbol of the last PDSCH transmission occasion (for example, the second PDSCH transmission occasion) and the start symbol of the PUCCH carrying the HARQ-ACK message is less than the PDSCH processing time, the terminal device 120, the terminal device 120 may provide no HARQ-ACK feedback or provide a HARQ-ACK message indicating NACK to the network device 110.

FIG. 3A illustrates an example of such embodiments. As shown in FIG. 3A, a first PDSCH transmission 310 occurs in sub-slot m (for example, in slot n) and a second PDSCH transmission 320 occurs in sub-slot m+ p (for example, in slot n) , where p is an integer and 0 ≤ p ≤ 7 or 1 ≤ p ≤ 6 (for example, p = 1) . If the sub-slot offset for HARQ-ACK feedback is configured as k, the HARQ-ACK feedback 330 may occur in sub-slot m+ k. For example, the terminal device 120 may provide a valid HARQ-ACK message if the time offset between the last symbol of the second PDSCH transmission 320 and the start symbol of the PUCCH carrying the HARQ-ACK message 330 is greater than or equal to the PDSCH processing time.

In this event, Clause 5.3 of the 3GPP specification TS 38.214 regarding the PDSCH processing time can be updated as below. If the first uplink symbol of the PUCCH which carries the HARQ-ACK information, as defined by the assigned HARQ-ACK timing K ₁ and the PUCCH resource to be used and including the effect of the timing advance, starts no earlier than at symbol L ₁, where L ₁ is defined as the next uplink symbol with its CP starting after T _proc, 1= (N ₁+d _1, 1) (2048+144) ·κ2 ^-μ·T _C after the end of the last symbol of the PDSCH or the last PDSCH transmission occasion (if the number of PDSCH transmission occasions is greater than 1; for example, the number of PDSCH transmission occasions may be 2) carrying the TB being acknowledged, then the UE shall provide a valid HARQ-ACK message.

Alternatively, in some embodiments, if a time offset between the last symbol of any of the first and second PDSCH transmission occasions and the start symbol of the PUCCH carrying the HARQ-ACK message is greater than or equal to the PDSCH processing time, the terminal device 120 may provide a valid HARQ-ACK message. For example, if any one of the PDSCH transmission occasions or a soft combination of the PDSCH transmission occasions is decoded by the terminal device 120 successfully, the terminal device 120 may provide the HARQ-ACK message indicating an acknowledgement (ACK) . For another example, if none of the PDSCH transmission occasions and a soft combination of the PDSCH transmission occasions is decoded by the terminal device 120 successfully, the terminal device 120 may provide the HARQ-ACK message indicating a negative acknowledgement (NACK) . For another example, if the time offset between the last symbol of any of the first and second PDSCH transmission occasions and the start symbol of the PUCCH carrying the HARQ-ACK message is less than the PDSCH processing time, the terminal device 120 may provide no HARQ-ACK feedback or provide a HARQ-ACK message indicating NACK to the network device 110.

FIG. 3B illustrates an example of such embodiments. As shown in FIG. 3B, a first PDSCH transmission 310 occurs in sub-slot m (for example, in slot n) and a second PDSCH transmission 320 occurs in sub-slot m+ p (for example, in slot n) , where p is an integer and 0 ≤ p ≤ 7 or 1 ≤ p ≤ 6 (for example, p = 1) . If the sub-slot offset for HARQ-ACK feedback is configured as k, the HARQ-ACK feedback 330 may occur in sub-slot m+ k. For example, the terminal device 120 may provide a valid HARQ-ACK message if the time offset between the last symbol of the first PDSCH transmission 310 and the start symbol of the PUCCH carrying the HARQ-ACK message 330 is greater than or equal to the PDSCH processing time.

In this event, Clause 5.3 of the 3GPP specification TS 38.214 regarding the PDSCH processing time can be updated as below. If the first uplink symbol of the PUCCH which carries the HARQ-ACK information, as defined by the assigned HARQ-ACK timing K ₁ and the PUCCH resource to be used and including the effect of the timing advance, starts no earlier than at symbol L ₁, where L ₁ is defined as the next uplink symbol with its CP starting after T _proc, 1= (N ₁+d _1, 1) (2048+144) ·κ2 ^-μ·T _C after the end of the last symbol of the PDSCH or any one of PDSCH transmission occasions (if the number of PDSCH transmission occasions is greater than 1; for example, the number of PDSCH transmission occasions may be 2) carrying the TB being acknowledged, then the UE shall provide a valid HARQ-ACK message. For example, if the PDSCH transmission occasion (s) which ends no later than T _proc, 1= (N ₁+d _1, 1) (2048+144) ·κ2 ^-μ·T _C before the first uplink symbol of the PUCCH which carries the HARQ-ACK information is successfully decoded, the UE shall provide ACK; otherwise, the UE shall provide NACK.

In some embodiments, if there are M SLIVs (where M is an integer and M ≥ 1) in the TDRA table locating or starting or ending in the second sub-slot for the second PDSCH transmission, and if at least one of the M SLIVs overlaps with the time domain resource allocation of the second PDSCH transmission, the third sub-slot for HARQ-ACK feedback may be determined based on the sub-slot offset k and the second sub-slot including the second PDSCH transmission. For example, if the first PDSCH transmission occurs in sub-slot m (that is, the first sub-slot) and the second PDSCH transmission occurs in sub-slot m+p (that is, the second sub-slot) , where p is an integer and 0 ≤ p ≤ 7 or 1 ≤ p ≤ 6 (for example, p = 1) , the HARQ-ACK feedback may occur in sub-slot m+k+p (that is, the third sub-slot) .

FIG. 4 illustrates an example of such embodiments. As shown in FIG. 4, a first PDSCH transmission 410 occurs in sub-slot m of slot n and a second PDSCH transmission 420 occurs in sub-slot m+1 of slot n. If the sub-slot offset for HARQ-ACK feedback is configured as k, the HARQ-ACK feedback 430 may occur in sub-slot m+k+1.

In some embodiments, if there are M SLIVs (where M is an integer and M ≥ 1) in the TDRA table locating or starting or ending in the second sub-slot for the second PDSCH transmission, and if at least one of the M SLIVs overlaps with the time domain resource allocation of the second PDSCH transmission, the third sub-slot for HARQ-ACK feedback may be determined based on the sub-slot offset k and the second sub-slot including the second PDSCH transmission. Additionally, the HARQ-ACK information location or the feedback position in the HARQ-ACK codebook may be determined based on a SLIV (also referred to as “second SLIV” ) locating or starting or ending in the second sub-slot and overlapping with the second PDSCH transmission. For example, if more than one of the M SLIVs overlap with the time domain resource allocation of the second PDSCH transmission, the HARQ-ACK information location in the HARQ-ACK codebook may be determined based on any of the following: the SLIV with the earliest starting or ending symbol, the SLIV with the lowest index of starting or ending symbol, the SLIV with the lowest index of starting or ending OFDM symbol, or the SLIV with the lowest index in time domain resource allocation for PDSCH.

FIG. 5 illustrates an example TDRA table 500 in accordance with some embodiments of the present disclosure. There are three SLIVs in the TDRA table 500, including RI 0, RI 1 and RI 2. For example, RI 0 is configured for a first PDSCH transmission occasion 510, which indicates that time domain resources allocated for the first PDSCH transmission occasion 510. For example, the time domain resources allocated for the first PDSCH transmission occasion 510 starts from symbol #0 and occupy 4 symbols. The symbol offset X between the first PDSCH transmission occasion 510 and a second PDSCH transmission occasion 520 is 6. Therefore, time domain resources 530 for the second PDSCH transmission occasion 520 can be determined based on RI 0 and the symbol offset. For example, the time domain resources allocated for the second PDSCH transmission 520 starts from symbol #10 and occupy 4 symbols. As shown in FIG. 5, RI 2 ends in the same sub-slot as the second PDSCH transmission occasion 520 and overlaps with the second PDSCH transmission occasion 520. In this event, the feedback position in the HARQ-ACK codebook can be determined based on RI 2.

In some embodiments, if intra-slot repetition (that is, Scheme 3) is configured, one more SLIV for the second PDSCH transmission occasion may be added to the TDRA table for Type-1 HARQ-ACK codebook generation. That is, the TDRA table may include a SLIV (also referred to as “first SLIV” ) for the first PDSCH transmission occasion and another SLIV (also referred to as “third SLIV” ) for the second PDSCH transmission occasion. For example, if the first SLIV indicates a starting symbol index S (where S is an integer and 0 ≤ S ≤ 12) and a symbol length L (where L is an integer and 2 ≤ L ≤ 14) used for the first PDSCH transmission occasion and if the symbol offset between the first PDSCH transmission occasion and the second PDSCH transmission occasion is X (where X is an integer and 0 ≤ X ≤ 7; for example, X is configured by the parameter startingSymbolOffsetK) , the third SLIV may indicate a starting symbol index S+L+X and a symbol length L used for the second PDSCH transmission. In this case, the feedback position in the HARQ-ACK codebook may be determined based on the third SLIV for the second PDSCH transmission.

FIG. 6 illustrates an example TDRA table 600 in accordance with some embodiments of the present disclosure. There are four SLIVs in the TDRA table 600, including RI 0, RI 1, RI 2 and RI 3. For example, RI 0 is configured for a first PDSCH transmission occasion 610, which indicates that time domain resources allocated for the first PDSCH transmission 610. For example, the time domain resources allocated for the first PDSCH transmission 610 starts from symbol #0 and occupy 4 symbols. RI 3 is configured for a second PDSCH transmission occasion 620, which indicates that time domain resources allocated for the second PDSCH transmission occasion 620. For example, the time domain resources allocated for the second PDSCH transmission occasion 620 starts from symbol #10 and occupy 4 symbols. In this event, the feedback position in the HARQ-ACK codebook can be determined based on RI 3.

In some embodiments, if intra-slot repetition (that is, Scheme 3) is configured, one virtual SLIV for the second PDSCH transmission occasion may be assumed to be included in the TDRA table for Type-1 HARQ-ACK codebook generation. For example, if the first SLIV for the first PDSCH transmission indicates a starting symbol index S (where S is an integer and 0 ≤ S ≤ 12) and a symbol length L (where L is an integer and 2 ≤ L ≤ 14) used for the first PDSCH transmission occasion and if the symbol offset between the first PDSCH transmission occasion and the second PDSCH transmission occasion is X (where X is an integer and 0 ≤ X ≤ 7; for example, X is configured by the parameter startingSymbolOffsetK) , the virtual SLIV may indicate a starting symbol index S+L+X and a symbol length L used for the second PDSCH transmission. In this case, the feedback position in the HARQ-ACK codebook may be determined based on the virtual SLIV.

In some embodiments, in case that intra-slot repetition (that is, Scheme 3) is configured, for example, if the first SLIV for the first PDSCH transmission indicates a starting symbol index S (where S is an integer and 0 ≤ S ≤ 12) and a symbol length L (where L is an integer and 2 ≤ L ≤ 14) used for the first PDSCH transmission occasion and if the symbol offset between the first PDSCH transmission occasion and the second PDSCH transmission occasion is X (where X is an integer and 0 ≤ X ≤ 7; for example, X is configured by the parameter startingSymbolOffsetK) , the time domain resource allocation or the virtual SLIV for the second PDSCH transmission may indicate a starting symbol index S+L+X and a symbol length L used for the second PDSCH transmission. In some embodiments, at least one SLIV (for example, SLIV V) may be assumed to be included in the TDRA table for Type-1 HARQ-ACK codebook generation, where the SLIV V overlaps with the time domain resource allocation or the virtual SLIV for the second PDSCH transmission occasion, and/or where the SLIV V locates or starts or ends in the same sub-slot with the time domain resource allocation or the virtual SLIV for the second PDSCH transmission occasion. For example, the feedback position in the HARQ-ACK codebook may be determined based on the SLIV V. For another example, the feedback position in the HARQ-ACK codebook may be determined based on any of the following: the SLIV V with the earliest starting or ending symbol, the SLIV V with the lowest index of starting or ending symbol, the SLIV V with the lowest index of starting or ending OFDM symbol, or the SLIV V with the lowest index in time domain resource allocation for PDSCH.

In some embodiments, if sub-slot based Type-1 HARQ-ACK feedback is configured, the third sub-slot for HARQ-ACK feedback may be determined based on the second sub-slot for the second PDSCH transmission occasion and the sub-slot offset k. For example, if the first PDSCH transmission occurs in sub-slot m, the second PDSCH transmission occurs in sub-slot n and the sub-slot offset for HARQ-ACK feedback is k, the HARQ-ACK feedback may be transmitted in a PUCCH in sub-slot n+k. In some embodiments, k+ (n–m) is assumed to be included in the HARQ-ACK timing values K1 configured to the terminal device 120, so as to ensure that a feedback position for the first PDSCH transmission can be found in the HARQ-ACK codebook. In this event, the terminal device 120 may use the feedback position for the first PDSCH transmission to report HARQ-ACK information for the PDSCH.

In some embodiments, if sub-slot based Type-1 HARQ-ACK feedback is configured, the third sub-slot for HARQ-ACK feedback may be determined based on the second sub-slot for the second PDSCH transmission occasion and the sub-slot offset k. For example, if the first PDSCH transmission occurs in sub-slot m, the second PDSCH transmission occurs in sub-slot n and the sub-slot offset for HARQ-ACK feedback is k, the HARQ-ACK feedback may be transmitted in a PUCCH in sub-slot n+k. In some embodiments, if the terminal device 120 cannot find a feedback position based on the SLIV configured for the first PDSCH transmission in the HARQ-ACK codebook, the terminal device 120 may add an additional feedback position at the end of the HARQ-ACK codebook. In this event, the terminal device 120 may use the additional feedback position to report HARQ-ACK information for the PDSCH.

It is to be understood that the above schemes for HARQ-ACK feedback can be combined in any suitable manner and the scope of the present disclosure is not limited in this aspect.

FIG. 7 illustrates a flowchart of an example method 700 in accordance with some embodiments of the present disclosure. The method 700 can be performed at the network device 110 as shown in FIG. 1 and/or FIG. 2. It is to be understood that the method 700 may include additional blocks not shown and/or may omit some blocks as shown, and the scope of the present disclosure is not limited in this regard.

At block 710, the network device 110 transmits, to the terminal device 120, a first PDSCH repetition in a first sub-slot and a second PDSCH repetition in a second sub-slot.

At block 720, the network device 110 receives a HARQ-ACK message from the terminal device 120 in a third sub-slot, where the third sub-slot is determined based on a sub-slot offset for HARQ-ACK feedback and one of the first and second sub-slots.

In some embodiments, the network device 110 may determine the third sub-slot based on the sub-slot offset and the first sub-slot.

In some embodiments, the HARQ-ACK message may comprise a feedback for the first and second PDSCH repetitions. The network device 110 may determine, from a TDRA table comprising a plurality of SLIVs, a first SLIV configured for the first PDSCH repetition. The network device 110 may determine a position of the feedback in the HARQ-ACK message based on the first SLIV and extract the feedback from the determined position.

In some embodiments, in response to a time offset between a last symbol of any of the first and second PDSCH repetitions and a start symbol of a physical uplink control channel (PUCCH) carrying the HARQ-ACK message being greater than or equal to PDSCH processing time, the network device 110 may receive the HARQ-ACK message from the terminal device 120 in the third sub-slot.

In some embodiments, the network device 110 may determine the third sub-slot based on the sub-slot offset and the second sub-slot.

In some embodiments, the HARQ-ACK message may comprise a feedback for the first and second PDSCH repetitions. The network device 110 may determine, from a TDRA table comprising a plurality of SLIVs, a second SLIV locating or starting or ending in the second sub-slot and overlapping with the second PDSCH repetition. The network device 110 may determine a position of the feedback in the HARQ-ACK message based on the second SLIV and extract the feedback from the determined position.

In some embodiments, the HARQ-ACK message may comprise a feedback for the first and second PDSCH repetitions. The network device 110 may determine, from a TDRA table comprising a plurality of SLIVs, a first SLIV configured for the first PDSCH repetition. The network device 110 may determine a third SLIV for the second PDSCH repetition based on the first SLIV and a symbol offset between the first PDSCH repetition and the second PDSCH repetition. The network device 110 may determine a position of the feedback in the HARQ-ACK message based on the second SLIV and extract the feedback from the determined position.

In some embodiments, in response to none of the first PDSCH repetition, the second PDSCH repetition and a soft combination of the first and second PDSCH repetitions being decoded by the terminal device successfully, the network device 110 may extract the feedback indicating an acknowledgement (ACK) from the determined position.

In some embodiments, in response to none of the first PDSCH repetition, the second PDSCH repetition and a soft combination of the first and second PDSCH repetitions being decoded by the terminal device successfully, the network device 110 may extract the feedback indicating a negative acknowledgement (NACK) from the determined position.

FIG. 8 illustrates a flowchart of an example method 800 in accordance with some embodiments of the present disclosure. The method 800 can be performed at the terminal device 120 as shown in FIG. 1 and/or FIG. 2. It is to be understood that the method 800 may include additional blocks not shown and/or may omit some blocks as shown, and the scope of the present disclosure is not limited in this regard.

At block 810, the terminal device 120 receives, from the network device 110, a first PDSCH repetition in a first sub-slot and a second PDSCH repetition in a second sub-slot.

At block 820, the terminal device 120 generates a HARQ-ACK message by decoding at least one of the first and second PDSCH repetitions.

At block 830, the terminal device 120 transmits the HARQ-ACK message to the network device in a third sub-slot, where the third sub-slot is determined based on a sub-slot offset for HARQ-ACK feedback and one of the first and second sub-slots.

In some embodiments, the terminal device 120 may determine the third sub-slot based on the sub-slot offset and the first sub-slot.

In some embodiments, the terminal device 120 may generate a feedback by decoding at least one of the first and second PDSCH repetitions. The terminal device 120 may determine, from a TDRA table comprising a plurality of SLIVs, a first SLIV configured for the first PDSCH repetition. The terminal device 120 may determine a position of the feedback in the HARQ-ACK message based on the first SLIV and generate the HARQ-ACK message by inserting the feedback at the determined position.

In some embodiments, in response to a time offset between a last symbol of any of the first and second PDSCH repetitions and a start symbol of a PUCCH carrying the HARQ-ACK message being greater than or equal to PDSCH processing time, the terminal device 120 may transmit the HARQ-ACK message to the network device 110 in the third sub-slot.

In some embodiments, the terminal device 120 may determine the third sub-slot based on the sub-slot offset and the second sub-slot.

In some embodiments, the terminal device 120 may generate a feedback by decoding at least one of the first and second PDSCH repetitions. The terminal device 120 may determine, from a TDRA table comprising a plurality of SLIVs, a second SLIV locating or starting or ending in the second sub-slot and overlapping with the second PDSCH repetition. The terminal device 120 may determine a position of the feedback in the HARQ-ACK message based on the second SLIV and generate the HARQ-ACK message by inserting the feedback at the determined position.

In some embodiments, the terminal device 120 may generate a feedback by decoding at least one of the first and second PDSCH repetitions. The terminal device 120 may determine, from a TDRA table comprising a plurality of SLIVs, a first SLIV configured for the first PDSCH repetition. The terminal device 120 may determine a third SLIV for the second PDSCH repetition based on the first SLIV and a symbol offset between the first PDSCH repetition and the second PDSCH repetition. The terminal device 120 may determine a position of the feedback in the HARQ-ACK message based on the third SLIV and generate the HARQ-ACK message by inserting the feedback at the determined position.

In some embodiments, in response to any of the first PDSCH repetition, the second PDSCH repetition and a soft combination of the first and second PDSCH repetitions being decoded by the terminal device successfully, the terminal device 120 may generate the feedback indicating an acknowledgement (ACK) .

In some embodiments, in response to none of the first PDSCH repetition, the second PDSCH repetition and a soft combination of the first and second PDSCH repetitions being decoded by the terminal device successfully, the terminal device 120 may generate the feedback indicating a negative acknowledgement (NACK) .

It can be seen that embodiments of the present disclosure provide a solution for HARQ-ACK feedback. According to this solution, a first PDSCH repetition is transmitted from a network device to a terminal device in a first sub-slot and a second PDSCH repetition is transmitted from the network device to the terminal device in a second sub-slot. The terminal device generates a HARQ-ACK message by decoding at least one of the first and second PDSCH repetitions. The HARQ-ACK message is transmitted from the terminal device to the network device in a third sub-slot determined based on a sub-slot offset for HARQ-ACK feedback and one of the first and second sub-slots. As such, embodiments of the present disclosure can support sub-slot based HARQ-ACK feedback. Moreover, no matter whether the third sub-slot is determined based on the first sub-slot or the second sub-slot, a HARQ-ACK position for the PDSCH can always be found in the HARQ-ACK codebook.

FIG. 9 is a simplified block diagram of a device 900 that is suitable for implementing embodiments of the present disclosure. The device 900 can be considered as a further example implementation of the network device 110 or the terminal device 120 as shown in FIG. 1 and/or FIG. 2. Accordingly, the device 900 can be implemented at or as at least a part of the network device 110 or the terminal device 120 as shown in FIG. 1 and/or FIG. 2.

As shown, the device 900 includes a processor 910, a memory 920 coupled to the processor 910, a suitable transmitter (TX) and receiver (RX) 940 coupled to the processor 910, and a communication interface coupled to the TX/RX 940. The memory 910 stores at least a part of a program 930. The TX/RX 940 is for bidirectional communications. The TX/RX 940 has at least one antenna to facilitate communication, though in practice an Access Node mentioned in this application may have several ones. The communication interface may represent any interface that is necessary for communication with other network elements, such as X2 interface for bidirectional communications between eNBs, S1 interface for communication between a Mobility Management Entity (MME) /Serving Gateway (S-GW) and the eNB, Un interface for communication between the eNB and a relay node (RN) , or Uu interface for communication between the eNB and a terminal device.

The program 930 is assumed to include program instructions that, when executed by the associated processor 910, enable the device 900 to operate in accordance with the embodiments of the present disclosure, as discussed herein with reference to FIG. 1 to 8. The embodiments herein may be implemented by computer software executable by the processor 910 of the device 900, or by hardware, or by a combination of software and hardware. The processor 910 may be configured to implement various embodiments of the present disclosure. Furthermore, a combination of the processor 910 and memory 920 may form processing means 950 adapted to implement various embodiments of the present disclosure.

The memory 920 may be of any type suitable to the local technical network and may be implemented using any suitable data storage technology, such as a non-transitory computer readable storage medium, semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples. While only one memory 920 is shown in the device 900, there may be several physically distinct memory modules in the device 900. The processor 910 may be of any type suitable to the local technical network, and may include one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs) and processors based on multicore processor architecture, as non-limiting examples. The device 900 may have multiple processors, such as an application specific integrated circuit chip that is slaved in time to a clock which synchronizes the main processor.

Generally, various embodiments of the present disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Some aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While various aspects of embodiments of the present disclosure are illustrated and described as block diagrams, flowcharts, or using some other pictorial representation, it will be appreciated that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

The present disclosure also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor, to carry out the process or method as described above with reference to FIG. 6 and/or FIG. 7. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, or the like that perform particular tasks or implement particular abstract data types. The functionality of the program modules may be combined or split between program modules as desired in various embodiments. Machine-executable instructions for program modules may be executed within a local or distributed device. In a distributed device, program modules may be located in both local and remote storage media.

Program code for carrying out methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the processor or controller, cause the functions/operations specified in the flowcharts and/or block diagrams to be implemented. The program code may execute entirely on a machine, partly on the machine, as a stand-alone software package, partly on the machine and partly on a remote machine or entirely on the remote machine or server.

The above program code may be embodied on a machine readable medium, which may be any tangible medium that may contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine readable medium may be a machine readable signal medium or a machine readable storage medium. A machine readable medium may include but not limited to an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the machine readable storage medium would include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM) , a read-only memory (ROM) , an erasable programmable read-only memory (EPROM or Flash memory) , an optical fiber, a portable compact disc read-only memory (CD-ROM) , an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

Further, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In certain circumstances, multitasking and parallel processing may be advantageous. Likewise, while several specific implementation details are contained in the above discussions, these should not be construed as limitations on the scope of the present disclosure, but rather as descriptions of features that may be specific to particular embodiments. Certain features that are described in the context of separate embodiments may also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment may also be implemented in multiple embodiments separately or in any suitable sub-combination.

Although the present disclosure has been described in language specific to structural features and/or methodological acts, it is to be understood that the present disclosure defined in the appended claims is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

A method of communication, comprising:

transmitting, from a network device to a terminal device, a first physical downlink shared channel (PDSCH) repetition in a first sub-slot and a second PDSCH repetition in a second sub-slot; and

receiving a hybrid automatic repeat request acknowledgement (HARQ-ACK) message from the terminal device in a third sub-slot, wherein the third sub-slot is determined based on a sub-slot offset for HARQ-ACK feedback and one of the first and second sub-slots.
The method of claim 1, further comprising:

determining the third sub-slot based on the sub-slot offset and the first sub-slot.
The method of claim 2, wherein the HARQ-ACK message comprises a feedback for the first and second PDSCH repetitions, and the method further comprises:

determining, from a time domain resource allocation (TDRA) table comprising a plurality of start and length indicator values (SLIVs) , a first SLIV configured for the first PDSCH repetition;

determining a position of the feedback in the HARQ-ACK message based on the first SLIV; and

extracting the feedback from the determined position.
The method of claim 2, wherein receiving the HARQ-ACK message from the terminal device comprises:

in response to a time offset between a last symbol of any of the first and second PDSCH repetitions and a start symbol of a physical uplink control channel (PUCCH) carrying the HARQ-ACK message being greater than or equal to PDSCH processing time, receiving the HARQ-ACK message from the terminal device in the third sub-slot.
The method of claim 1, further comprising:

determining the third sub-slot based on the sub-slot offset and the second sub-slot.
The method of claim 5, wherein the HARQ-ACK message comprises a feedback for the first and second PDSCH repetitions, and the method further comprises:

determining, from a TDRA table comprising a plurality of SLIVs, a second SLIV overlapping with the second PDSCH repetition;

determining a position of the feedback in the HARQ-ACK message based on the second SLIV; and

extracting the feedback from the determined position.
The method of claim 5, wherein the HARQ-ACK message comprises a feedback for the first and second PDSCH repetitions, and the method further comprises:

determining, from a TDRA table comprising a plurality of SLIVs, a first SLIV configured for the first PDSCH repetition;

determining a third SLIV for the second PDSCH repetition based on the first SLIV and a symbol offset between the first PDSCH repetition and the second PDSCH repetition;

determining a position of the feedback in the HARQ-ACK message based on the third SLIV; and

extracting the feedback from the determined position.
The method of any of claims 3, 6 and 7, wherein extracting the feedback from the determined position comprises:

in response to any of the first PDSCH repetition, the second PDSCH repetition and a soft combination of the first and second PDSCH repetitions being decoded by the terminal device successfully, extracting the feedback indicating an acknowledgement (ACK) from the determined position.
The method of any of claims 3, 6 and 7, wherein extracting the feedback from the determined position comprises:

in response to none of the first PDSCH repetition, the second PDSCH repetition and a soft combination of the first and second PDSCH repetitions being decoded by the terminal device successfully, extracting the feedback indicating a negative acknowledgement (NACK) from the determined position.
A method of communication, comprising:

receiving, at a terminal device and from a network device, a first physical downlink shared channel (PDSCH) repetition in a first sub-slot and a second PDSCH repetition in a second sub-slot;

generating a hybrid automatic repeat request acknowledgement (HARQ-ACK) message by decoding at least one of the first and second PDSCH repetitions; and

transmitting the HARQ-ACK message to the network device in a third sub-slot, wherein the third sub-slot is determined based on a sub-slot offset for HARQ-ACK feedback and one of the first and second sub-slots.
The method of claim 10, further comprising:

determining the third sub-slot based on the sub-slot offset and the first sub-slot.
The method of claim 11, wherein generating the HARQ-ACK message comprises:

generating a feedback by decoding at least one of the first and second PDSCH repetitions;

determining, from a time domain resource allocation (TDRA) table comprising a plurality of start and length indicator values (SLIVs) , a first SLIV configured for the first PDSCH repetition;

determining a position of the feedback in the HARQ-ACK message based on the first SLIV; and

generating the HARQ-ACK message by inserting the feedback at the determined position.
The method of claim 11, wherein transmitting the HARQ-ACK message to the network device comprises:

in response to a time offset between a last symbol of any of the first and second PDSCH repetitions and a start symbol of a physical uplink control channel (PUCCH) carrying the HARQ-ACK message being greater than or equal to PDSCH processing time, transmitting the HARQ-ACK message to the network device in the third sub-slot.
The method of claim 10, further comprising:

determining the third sub-slot based on the sub-slot offset and the second sub-slot.
The method of claim 14, wherein generating the HARQ-ACK message comprises:

generating a feedback by decoding at least one of the first and second PDSCH repetitions;

determining, from a TDRA table comprising a plurality of SLIVs, a second SLIV overlapping with the second PDSCH repetition;

determining a position of the feedback in the HARQ-ACK message based on the second SLIV; and

generating the HARQ-ACK message by inserting the feedback at the determined position.
The method of claim 14, wherein generating the HARQ-ACK message comprises:

generating a feedback by decoding at least one of the first and second PDSCH repetitions;

determining, from a TDRA table comprising a plurality of SLIVs, a first SLIV configured for the first PDSCH repetition;

determining a third SLIV for the second PDSCH repetition based on the first SLIV and a symbol offset between the first PDSCH repetition and the second PDSCH repetition;

determining a position of the feedback in the HARQ-ACK message based on the third SLIV; and

generating the HARQ-ACK message by inserting the feedback at the determined position.
The method of any of claims 12, 15 and 16, wherein generating the feedback comprises:

in response to any of the first PDSCH repetition, the second PDSCH repetition and a soft combination of the first and second PDSCH repetitions being decoded by the terminal device successfully, generating the feedback indicating an acknowledgement (ACK) .
The method of any of claims 12, 15 and 16, wherein generating the feedback comprises:

in response to none of the first PDSCH repetition, the second PDSCH repetition and a soft combination of the first and second PDSCH repetitions being decoded by the terminal device successfully, generating the feedback indicating a negative acknowledgement (NACK) .
A network device, comprising:

a processor; and

a memory coupled to the processor and storing instructions thereon, the instructions, when executed by the processor, causing the network device to perform the method according to any of claims 1 to 9.
A terminal device, comprising:

a processor; and

a memory coupled to the processor and storing instructions thereon, the instructions, when executed by the processor, causing the terminal device to perform the method according to any of claims 10 to 18.
A computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method according to any of claims 1 to 9.
A computer readable medium having instructions stored thereon, the instructions, when executed on at least one processor, causing the at least one processor to perform the method according to any of claims 10 to 18.