Patent Description:
Technical document <NPL>, discloses overlapping HARQ-ACK feedback in multiple HARQ-ACK codebooks.

Controller/processor <NUM> of base station <NUM>, controller/processor <NUM> of UE <NUM>, and/or any other component(s) of <FIG> may perform one or more techniques associated with HARQ-ACK reporting for downlink communications included in multiple downlink association sets, as described in more detail elsewhere herein. For example, controller/processor <NUM> of base station <NUM>, controller/processor <NUM> of UE <NUM>, and/or any other component(s) of <FIG> may perform or direct operations of, for example, process <NUM> of <FIG>, process <NUM> of <FIG>, process <NUM> of <FIG>, process <NUM> and <FIG>, and/or other processes as described herein. Memories <NUM> and <NUM> may store data and program codes for base station <NUM> and UE <NUM>, respectively.

In some aspects, UE <NUM> includes means for determining that a received physical downlink shared channel (PDSCH) communication is included in multiple downlink association sets, wherein hybrid automatic repeat request acknowledgement (HARQ-ACK) information for different downlink association sets is to be reported in different slots; means for reporting a valid HARQ-ACK in a first slot indicated by a PDSCH-to-HARQ feedback timing value associated with the PDSCH communication; means for selectively reporting the valid HARQ-ACK, corresponding to the PDSCH communication, or a negative acknowledgement (NACK) in a second slot based at least in part on whether the second slot occurs before or after the first slot, wherein the second slot is to be used for reporting HARQ-ACK information associated with a downlink association set of the multiple downlink association sets; and/or the like. The UE <NUM> includes means for setting a value in HARQ-ACK information to indicate a valid HARQ-ACK, corresponding to a PDSCH communication, or a NACK based at least in part on a PDSCH-to-HARQ feedback timing value associated with the PDSCH communication; means for transmitting the value in the HARQ-ACK information; and/or the like. In some aspects, such means may include one or more components of UE <NUM> described in connection with <FIG>.

In some aspects, base station <NUM> includes means for receiving a NACK in HARQ-ACK information, wherein the NACK corresponds to a PDSCH communication included in multiple downlink association sets; means for determining a first slot indicated by a PDSCH-to-HARQ feedback timing value associated with the PDSCH communication; means for selectively triggering retransmission of the PDSCH communication based at least in part on a timing of a second slot, in which the HARQ-ACK information is received, relative to the first slot; and/or the like. The base station <NUM> includes means for determining that a PDSCH communication, to be scheduled by the base station <NUM>, is associated with a plurality of downlink association sets corresponding to a plurality of PDSCH-to-HARQ feedback timing values that each indicate a different slot for reporting HARQ-ACK information for a downlink association set of the plurality of downlink association sets; means for determining a minimum PDSCH-to-HARQ feedback timing value of the plurality of PDSCH-to-HARQ feedback timing values; means for signaling, to a UE, the minimum PDSCH-to-HARQ feedback timing value in association with scheduling the PDSCH communication; and/or the like. In some aspects, such means may include one or more components of base station <NUM> described in connection with <FIG>.

<FIG> shows an example frame structure <NUM> for FDD in a telecommunications system (e.g., NR). In some aspects, a scheduling unit for the FDD may frame-based, subframe-based, slot-based, symbol-based, and/or the like.

<FIG> is a diagram <NUM> showing an example of a DL-centric slot or wireless communication structure. The DL-centric slot may include a control portion <NUM>. The control portion <NUM> may exist in the initial or beginning portion of the DL-centric slot. The control portion <NUM> may include various scheduling information and/or control information corresponding to various portions of the DL-centric slot. In some aspects, the control portion <NUM> may include legacy PDCCH information, shortened PDCCH (sPDCCH) information), a control format indicator (CFI) value (e.g., carried on a physical control format indicator channel (PCFICH)), one or more grants (e.g., downlink grants, uplink grants, and/or the like), and/or the like.

The DL-centric slot may also include a DL data portion <NUM>. The DL data portion <NUM> may sometimes be referred to as the payload of the DL-centric slot. In some configurations, the DL data portion <NUM> may be a physical downlink shared channel (PDSCH).

The DL-centric slot may also include an UL short burst portion <NUM>. The UL short burst portion <NUM> may sometimes be referred to as an UL burst, an UL burst portion, a common UL burst, a short burst, an UL short burst, a common UL short burst, a common UL short burst portion, and/or various other suitable terms. In some aspects, the UL short burst portion <NUM> may include one or more reference signals. Additionally, or alternatively, the UL short burst portion <NUM> may include feedback information corresponding to various other portions of the DL-centric slot. For example, the UL short burst portion <NUM> may include feedback information corresponding to the control portion <NUM> and/or the data portion <NUM>. Non-limiting examples of information that may be included in the UL short burst portion <NUM> include HARQ-ACK feedback (e.g., an ACK or a NACK), an ACK signal (e.g., a PUCCH ACK, a PUSCH ACK, an immediate ACK), a NACK signal (e.g., a PUCCH NACK, a PUSCH NACK, an immediate NACK), a scheduling request (SR), a buffer status report (BSR), a HARQ indicator, a channel state indication (CSI), a channel quality indicator (CQI), a sounding reference signal (SRS), a demodulation reference signal (DMRS), PUSCH data, and/or various other suitable types of information. The UL short burst portion <NUM> may include additional or alternative information, such as information pertaining to random access channel (RACH) procedures, scheduling requests, and various other suitable types of information.

In some aspects, a downlink slot may be a DL-centric slot or a DL-only slot. A DL-only slot may exclude the UL short burst portion <NUM>, such that the DL-only slot includes only downlink portions (e.g., DL control portion <NUM> and DL data portion <NUM>).

<FIG> is a diagram <NUM> showing an example of an UL-centric slot or wireless communication structure. The UL-centric slot may include a control portion <NUM>. The control portion <NUM> may exist in the initial or beginning portion of the UL-centric slot. The control portion <NUM> in <FIG> may be similar to the control portion <NUM> described above with reference to <FIG>. The UL-centric slot may also include an UL long burst portion <NUM>. The UL long burst portion <NUM> may sometimes be referred to as the payload of the UL-centric slot. The UL portion may refer to the communication resources utilized to communicate UL data from the subordinate entity (e.g., UE) to the scheduling entity (e.g., UE or BS). In some configurations, the control portion <NUM> may be a physical DL control channel (PDCCH).

The UL-centric slot may also include an UL short burst portion <NUM>. The UL short burst portion <NUM> in <FIG> may be similar to the UL short burst portion <NUM> described above with reference to <FIG>, and may include any of the information described above in connection with <FIG>. The foregoing is merely one example of an UL-centric wireless communication structure, and alternative structures having similar features may exist without necessarily deviating from the aspects described herein.

In some aspects, an uplink slot may be an UL-centric slot or an UL-only slot. An UL-only slot may exclude the DL control portion <NUM>, such that the UL-only slot includes only uplink portions (e.g., UL long burst portion <NUM> and UL short burst portion <NUM>).

In some aspects, the sidelink signals may be communicated using a licensed spectrum (unlike wireless local area networks, which typically use an unlicensed spectrum).

In one example, a wireless communication structure, such as a frame, may include both UL-centric slots and DL-centric slots. In this example, the ratio of UL-centric slots to DL-centric slots in a frame may be dynamically adjusted based at least in part on the amount of UL data and the amount of DL data that are transmitted. For example, if there is more UL data, then the ratio of UL-centric slots to DL-centric slots may be increased. Conversely, if there is more DL data, then the ratio of UL-centric slots to DL-centric slots may be decreased.

<FIG> is a diagram illustrating an example <NUM> of HARQ-ACK reporting for a downlink communication included in a single downlink association set, in accordance with various aspects of the present disclosure.

As shown in <FIG>, a UE <NUM> may receive a physical downlink shared channel (PDSCH) communication that is associated with a single downlink association set. A downlink association set may refer to a set of downlink slots (e.g., downlink-centric slots, downlink-only slots, and/or the like) for which a corresponding acknowledgement (ACK) or negative acknowledgement (NACK) are to be reported in a same slot in the same hybrid automatic repeat request acknowledgement (HARQ-ACK) information that is generated according to the same HARQ-ACK codebook.

In some aspects, a downlink association set may be determined based at least in part on a preconfigured set of PDSCH-to-HARQ feedback timing values, which may also be referred to as K1 values in the 3GPP standard. A PDSCH-to-HARQ feedback timing value may indicate a timing (e.g., a number of slots) between a last slot of a PDSCH communication, to which the PDSCH-to-HARQ feedback timing value corresponds, and a slot in which HARQ-ACK feedback, corresponding to the PDSCH communication, is to be transmitted. Thus, the PDSCH-to-HARQ timing value may indicate a slot in which HARQ-ACK feedback, corresponding to the PDSCH communication, is to be transmitted. In some aspects, a UE <NUM> may receive a PDSCH-to-HARQ timing value in downlink control information (DCI) that schedules the PDSCH communication. A PDSCH-to-HARQ feedback timing value may be referred to herein as a PDSCH-to-HARQ timing value or a K1 value for brevity.

In some aspects, a set of K1 values may be preconfigured (e.g., for a UE <NUM>, for a cell, and/or the like). In this case, the preconfigured set of K1 values may be indicated in a radio resource control (RRC) message, a system information block (SIB), and/or the like. For example, a set of preconfigured K1 values may be indicated in an RRC message, and a particular K1 value may be selected from the set by a base station <NUM> when scheduling a PDSCH communication. The selected K1 value may be indicated by the base station <NUM> to the UE <NUM> in DCI, such as a downlink grant that schedules the PDSCH communication to which the selected K1 value corresponds.

As indicated above, a UE <NUM> may determine a downlink association set for a PDSCH communication based at least in part on a preconfigured set of K1 values indicated to a UE <NUM>. For example, the UE <NUM> may identify a HARQ-ACK reporting occasion, such as a slot in which HARQ-ACK feedback is to be transmitted on a physical uplink control channel (PUCCH) or as uplink control information (UCI) piggybacked on a physical uplink shared channel (PUSCH). The UE <NUM> may then identify each slot that occurs K1 slots before the HARQ-ACK reporting occasion, for each K1 value in a preconfigured set of K1 values. If an identified slot is an uplink slot, then the uplink slot may be removed from the set of slots to form the downlink association set. Thus, the downlink association set for a HARQ-ACK reporting occasion includes only downlink slots for which a K1 value, of the preconfigured set of K1 values, points to a slot that includes the HARQ-ACK reporting occasion.

In the HARQ-ACK reporting occasion, the UE <NUM> may report HARQ-ACK information, generated according to a HARQ-ACK codebook, which may be used to indicate an ACK or a NACK for slots included in the downlink association set corresponding to the HARQ-ACK reporting occasion. In some aspects, the HARQ-ACK codebook may be semi-statically configured (e.g., a semi-static HARQ-ACK codebook, a Type <NUM> HARQ-ACK codebook, and/or the like). In this case, a size (e.g., a number of bits) of the HARQ-ACK codebook may be determined solely by a set of semi-static configurations (e.g., which may be indicated in an RRC message, system information, and/or the like). For example, the size of a semi-statically configured HARQ-ACK codebook may be determined based at least in part on a number of K1 values included in the preconfigured set of K1 values, a number of component carriers in a PUCCH group, an UL-DL TDD configuration, a supported number of non-overlapped PDSCH per slot, a UE capability regarding a number of PDSCH that can be supported per slot, a number of code block groups (CBGs) per component carrier, and/or the like. In some aspects, a size of the HARQ-ACK codebook may be determined based at least in part on the number of slots included in the downlink association set corresponding to the HARQ-ACK codebook.

As an example, and as shown in <FIG>, a UE <NUM> may receive a PDSCH communication (e.g., in a slot shown as slot <NUM>). As shown by reference number <NUM>, the preconfigured set of K1 values for the UE <NUM> may include three K1 values, shown as <NUM>, <NUM>, and <NUM>. In example <NUM>, the PDSCH communication is scheduled with a K1 value of <NUM>. Thus, HARQ-ACK information, that includes HARQ-ACK feedback for the PDSCH communication, is to be transmitted in slot <NUM>, which occurs <NUM> slots after slot <NUM> in which the PDSCH communication is received.

As shown by reference number <NUM>, in example <NUM>, the downlink association set for the HARQ-ACK information to be transmitted in slot <NUM> includes slots <NUM>, <NUM>, and <NUM>. This may be determined using the preconfigured set of K1 values, since slot <NUM> occurs <NUM> slots before slot <NUM>, slot <NUM> occurs <NUM> slots before slot <NUM>, and slot <NUM> occurs <NUM> slots before slot <NUM>. In this case, slots <NUM>, <NUM>, and <NUM> are downlink slots, and thus are included in the downlink association set. If a slot <NUM>, <NUM>, or <NUM> were an uplink slot, then that slot would not be included in the downlink association set.

As shown by reference number <NUM>, in example <NUM>, assume that a PDSCH communication is not scheduled, received, and/or successfully decoded in slots <NUM> and <NUM>, while a PDSCH communication is received and successfully decoded in slot <NUM>. As a result, and as shown by reference number <NUM>, the UE <NUM> reports HARQ-ACK information, for this downlink association set, of NACK (e.g., corresponding to slot <NUM>, in which a PDSCH communication is not scheduled, received, or successfully decoded), ACK (e.g., corresponding to slot <NUM>, in which a PDSCH communication is successfully received and decoded), and NACK (e.g., corresponding to slot <NUM>, in which a PDSCH communication is not scheduled, received, or successfully decoded).

In <FIG>, the PDSCH communication received in slot <NUM> belongs to a single downlink association set (e.g., for the HARQ-ACK information transmitted in slot <NUM>). However, as will be described in more detail below in connection with <FIG>, in some aspects, a PDSCH communication may belong to multiple downlink association sets. In this case, the UE <NUM> may need to determine how to handle HARQ-ACK reporting across multiple HARQ-ACK information transmissions corresponding to the multiple downlink association sets. Furthermore, a base station <NUM> may need to determine how to interpret HARQ-ACK information for the different downlink association sets. Additional details are described below.

<FIG> is a diagram illustrating an example <NUM> of HARQ-ACK reporting for downlink communications included in multiple downlink association sets, in accordance with various aspects of the present disclosure.

As shown in <FIG>, in some aspects, a PDSCH communication may be included in multiple downlink association sets, where HARQ-ACK information for different downlink association sets is to be reported in different slots. For example, as shown by reference number <NUM>, a UE <NUM> may receive an indication (e.g., in an RRC message) of a preconfigured set of K1 values, shown as <NUM>, <NUM>, and <NUM>. Using this set of K1 values and a set of determined HARQ-ACK reporting occasions, the UE <NUM> may determine that a PDSCH communication received in slot <NUM> is included in three downlink association sets. As described above in connection with <FIG>, a HARQ-ACK codebook, for the HARQ-ACK information, may be semi-statically configured.

The first downlink association set (shown as "DAS A" or simply "A") includes slots <NUM>, <NUM>, and <NUM>, and the HARQ-ACK information for the first downlink association set is reported in slot <NUM> (e.g., based at least in part on a K1 value of one or more PDSCH communications pointing to slot <NUM>). The second downlink association set (shown as "DAS B" or simply "B") includes slots <NUM>, <NUM>, and <NUM>, and the HARQ-ACK information for the second downlink association set is reported in slot <NUM>. The third downlink association set (shown as "DAS C" or simply "C") includes slots <NUM>, <NUM>, and <NUM>, and the HARQ-ACK information for the first downlink association set is reported in slot <NUM>. This number of downlink association sets (e.g., three) is provided as an example, and a PDSCH communication may belong to a different number of multiple downlink association sets (e.g., two sets, four sets, five sets, and/or the like) depending on a number of preconfigured K1 values, an UL/DL slot configuration, and/or the like.

When a PDSCH communication is included in multiple downlink association sets, the UE <NUM> may need to determine how to handle HARQ-ACK reporting for multiple HARQ-ACK information transmissions corresponding to the multiple downlink association sets. For example, the UE <NUM> may need to determine, for each HARQ-ACK information transmission, whether to report a valid HARQ-ACK (e.g., valid HARQ-ACK feedback) or a NACK. As used herein, a valid HARQ-ACK (sometimes referred to as a HARQ-ACK) is determined based at least in part on a result of decoding the PDSCH communication. The valid HARQ-ACK may be an ACK if the PDSCH communication is successfully decoded, or may be a NACK if the PDSCH communication is not successfully decoded.

In some aspects, the UE <NUM> may report a valid HARQ-ACK for the PDSCH communication only in HARQ-ACK information indicated by the K1 value for the PDSCH communication, and may report a NACK in the other HARQ-ACK information transmissions corresponding to the PDSCH communication. However, this may waste resources if the HARQ-ACK information indicated by the K1 value is not successfully decoded by a base station <NUM> since the base station <NUM> will not be able to use another HARQ-ACK information transmission to read a valid HARQ-ACK for the PDSCH communication. This may result in a larger number of retransmissions of PDSCH communications (thereby wasting network resources, UE resources, and base station resources) as compared to repeating the valid HARQ-ACK in multiple HARQ-ACK information transmissions.

In some aspects, the UE <NUM> may report a valid HARQ-ACK for the PDSCH communication in all HARQ-ACK information corresponding to the PDSCH communication (e.g., all HARQ-ACK information transmissions for all downlink association sets that include the PDSCH communication). However, this may reduce a HARQ-ACK processing timeline for the UE <NUM> if there is a HARQ-ACK reporting occasion that occurs before the HARQ-ACK reporting occasion indicated by the K1 value. As a result, the UE <NUM> may consume additional resources (e.g., processing power, battery power, and/or the like) to comply with the shorter HARQ-ACK processing timeline, and/or may be constrained by delaying other types of processing until after the HARQ-ACK feedback is processed.

Some techniques and apparatuses described herein conserve UE resources and reduce UE processing constraints for HARQ-ACK feedback, while also reducing a number of PDSCH retransmissions by repeating HARQ-ACK feedback without consuming additional UE resources. Additional details are described below.

As shown by reference number <NUM>, the PDSCH communication in slot <NUM> may be associated with a K1 value (e.g., a PDSCH-to-HARQ feedback timing value) of <NUM>. For example, a downlink grant that schedules the PDSCH communication may indicate the K1 value of <NUM> for the PDSCH communication.

As shown by reference number <NUM>, the HARQ-ACK information corresponding to the K1 value of <NUM> may be transmitted in a first slot, shown as slot <NUM> (e.g., which occurs K1=<NUM> slots after slot <NUM>, in which the PDSCH communication is received). Because the PDSCH communication is scheduled with K1=<NUM>, the UE <NUM> may report a valid HARQ-ACK in the HARQ-ACK information transmitted in slot <NUM>. In example <NUM>, the valid HARQ-ACK is an ACK because the PDSCH communication in slot <NUM> is successfully decoded by the UE <NUM>. As shown, the ACK is reported as a second value in the HARQ-ACK information (e.g., which includes <NUM> values) because the slot in which the PDSCH communication is received (e.g., slot <NUM>) occurs second in time among the slots included in the downlink association set corresponding to the HARQ-ACK information transmitted in slot <NUM>. In this case, the UE <NUM> reports a first value for slot <NUM>, a second value for slot <NUM>, and a third value for slot <NUM> in the HARQ-ACK information. In <FIG>, a question mark represents a value, in HARQ-ACK information, corresponding to a different slot than slot <NUM>.

For the other HARQ-ACK information transmissions associated with the PDSCH communication (e.g., the HARQ-ACK information transmissions not associated with the K1 value), the UE <NUM> may determine whether to report a valid HARQ-ACK (e.g., an ACK or a NACK depending on a result of decoding the PDSCH communication) or a NACK (e.g., that does not depend on a result of decoding the PDSCH communication). In some aspects, the UE <NUM> may determine whether to report the valid HARQ-ACK or the NACK in HARQ-ACK information based at least in part on whether a slot (e.g., a second slot), in which the HARQ-ACK information is to be transmitted, occurs before or after a first slot indicated by the K1 value.

For example, as shown by reference number <NUM>, if the HARQ-ACK information is to be transmitted in a second slot (e.g., slot <NUM>) that occurs before a first slot (e.g., slot <NUM>) indicated by the K1 value, then the UE <NUM> may report a NACK for a value corresponding to the PDSCH communication. This NACK may not depend on a result of decoding the PDSCH communication, and this NACK may be reported regardless of whether the PDSCH communication is successfully decoded (e.g., regardless of whether decoding the PDSCH communication result in an ACK or a NACK). In some aspects, the NACK may be reported before HARQ-ACK processing of the PDSCH communication is complete (e.g., where a result of decoding is unknown when the HARQ-ACK information is transmitted). In this way, the UE <NUM> need not expend additional processing resources or constrain other processing by reducing a HARQ-ACK reporting timeline (e.g., from K1=<NUM> to K1=<NUM>).

As further shown by reference number <NUM>, the NACK is reported as a third value in the HARQ-ACK information (e.g., which includes <NUM> values) because the slot in which the PDSCH communication is received (e.g., slot <NUM>) occurs third in time among the slots included in the downlink association set corresponding to the HARQ-ACK information transmitted in slot <NUM>. In this case, the UE <NUM> reports a first value for slot <NUM>, a second value for slot <NUM>, and a third value for slot <NUM> in the HARQ-ACK information.

As another example, as shown by reference number <NUM>, if the HARQ-ACK information is to be transmitted in a second slot (e.g., slot <NUM>) that occurs after a first slot (e.g., slot <NUM>) indicated by the K1 value, then the UE <NUM> may report a valid HARQ-ACK for a value corresponding to the PDSCH communication. This HARQ-ACK may depend on a result of decoding the PDSCH communication, and may be reported as an ACK if the PDSCH communication is successfully decoded or a NACK if the PDSCH communication is not successfully decoded. In this way, the UE <NUM> may repeat the valid HARQ-ACK, transmitted in a slot indicated by the K1 value, in one or more HARQ-ACK reporting occasions (e.g., if any exist) that occur after the slot indicated by the K1 value. This may not consume any additional processing resources because the UE <NUM> must report a value in these one or more HARQ-ACK reporting occasions, and may permit a base station <NUM> to receive the valid HARQ-ACK even if the HARQ-ACK information in the slot indicated by the K1 value is not successfully decoded by the base station <NUM>.

As further shown by reference number <NUM>, the valid HARQ-ACK (shown as an ACK in example <NUM>) is reported as a first value in the HARQ-ACK information (e.g., which includes <NUM> values) because the slot in which the PDSCH communication is received (e.g., slot <NUM>) occurs first in time among the slots included in the downlink association set corresponding to the HARQ-ACK information transmitted in slot <NUM>. In this case, the UE <NUM> reports a first value for slot <NUM>, a second value for slot <NUM>, and a third value for slot <NUM> in the HARQ-ACK information.

Thus, for particular HARQ-ACK information, the UE <NUM> may set a value, corresponding to a slot in which the PDSCH communication is received, to indicate a valid HARQ-ACK for the PDSCH communication (e.g., an ACK or a NACK depending on a result of decoding the PDSCH communication) or a NACK (e.g., that does not depend on a result of decoding the PDSCH communication) based at least in part on the K1 value associated with the PDSCH communication. For example, the UE <NUM> may set the value to indicate the valid HARQ-ACK if the HARQ-ACK information is to be transmitted in a slot indicated by the K1 value or a later slot (e.g., that occurs after the slot indicated by the K1 value). Conversely, the UE <NUM> may set the value to indicate the NACK if the HARQ-ACK information is to be transmitted in a slot that is earlier than a slot indicated by the K1 value (e.g., a slot that occurs before the slot indicated by the K1 value).

When a base station <NUM> receives HARQ-ACK information that includes a value for a slot and/or a PDSCH communication included in multiple downlink association sets, the base station <NUM> may need to determine how to interpret the value. If the HARQ-ACK information is received in a slot indicated by the K1 value for the PDSCH communication, or a slot that occurs after the slot indicated by the K1 value, then the base station <NUM> may interpret the value as a valid HARQ-ACK, and may perform further processing using the valid HARQ-ACK. Conversely, if the HARQ-ACK information is received in a slot before the slot indicated by the K1 value, then the base station <NUM> may not interpret the value as a valid HARQ-ACK, and may discard the value, thereby conserving processing resources of the base station <NUM>.

For example, the base station <NUM> may receive a NACK in HARQ-ACK information, and the NACK may correspond to a PDSCH communication (or a slot of the PDSCH communication) that is included in multiple downlink association sets. The base station <NUM> may determine a first slot indicated by a K1 value associated with the PDSCH communication. The base station <NUM> may selectively trigger retransmission (e.g., due to the NACK) based at least in part on a timing of a second slot, in which the HARQ-ACK information is received, relative to the first slot. For example, if the second slot is the same slot as the first slot, or if the second slot occurs after the first slot, then the NACK may be valid HARQ-ACK feedback for the PDSCH communication, and the base station <NUM> may trigger retransmission of the PDSCH communication. However, if the second slot occurs before the first slot, then the NACK may not depend on a result of decoding the PDSCH communication (e.g., may not be valid HARQ-ACK feedback), and the base station <NUM> may not trigger retransmission of the PDSCH communication (e.g., unless later received valid HARQ-ACK feedback indicates a NACK for the PDSCH communication). In this way, network resources may be conserved by triggering retransmissions only in response to valid HARQ-ACK feedback.

In some aspects, the base station <NUM> may always select and indicate a minimum permissible K1 value (e.g., that corresponds to a valid HARQ-ACK reporting occasion) for a PDSCH communication. For example, the base station <NUM> may determine that a PDSCH communication, to be scheduled by the base station <NUM>, is associated with multiple downlink association sets corresponding to multiple K1 values. The base station <NUM> may determine a minimum K1 value from the multiple K1 values, and may signal the minimum K1 value to the UE <NUM> in association with scheduling the PDSCH communication. In some aspects, the base station <NUM> may prevent a K1 value other than the minimum K1 value from being signaled to the UE <NUM>. In this case, the UE <NUM> may always repeat valid HARQ-ACK, corresponding to the PDSCH communication, in all HARQ-ACK information transmissions, and may conserve UE resources that would otherwise be used to determine whether to transmit a valid HARQ-ACK or a NACK for different HARQ-ACK information transmissions.

<FIG> is a diagram illustrating an example process <NUM> performed, for example, by a UE, in accordance with various aspects of the present disclosure. Example process <NUM> is an example where a UE (e.g., UE <NUM> and/or the like) performs operations associated with HARQ-ACK reporting for downlink communications included in multiple downlink association sets.

As shown in <FIG>, in some aspects, process <NUM> includes determining that a received PDSCH communication is included in multiple downlink association sets, wherein HARQ-ACK information for different downlink association sets is to be reported in different slots (block <NUM>). For example, the UE (e.g., using controller/processor <NUM> and/or the like) determines that a received PDSCH communication is included in multiple downlink association sets, as described above in connection with <FIG>. In some aspects, HARQ-ACK information for different downlink association sets is to be reported in different slots.

As further shown in <FIG>, in some aspects, process <NUM> includes reporting a valid HARQ-ACK in a first slot indicated by a PDSCH-to-HARQ feedback timing value associated with the PDSCH communication (block <NUM>). For example, the UE (e.g., using controller/processor <NUM>, transmit processor <NUM>, TX MIMO processor <NUM>, MOD <NUM>, antenna <NUM>, and/or the like) reports a valid HARQ-ACK in a first slot indicated by a PDSCH-to-HARQ feedback timing value associated with the PDSCH communication, as described above in connection with <FIG>.

As further shown in <FIG>, in some aspects, process <NUM> includes selectively reporting the valid HARQ-ACK, corresponding to the PDSCH communication, or a NACK in a second slot based at least in part on whether the second slot occurs before or after the first slot, wherein the second slot is to be used for reporting HARQ-ACK information associated with a downlink association set of the multiple downlink association sets (block <NUM>). For example, the UE (e.g., using controller/processor <NUM>, transmit processor <NUM>, TX MIMO processor <NUM>, MOD <NUM>, antenna <NUM>, and/or the like) selectively reports the valid HARQ-ACK, corresponding to the PDSCH communication, or a NACK in a second slot based at least in part on whether the second slot occurs before or after the first slot, as described above in connection with <FIG>. In some aspects, the second slot is to be used for reporting HARQ-ACK information associated with a downlink association set of the multiple downlink association sets.

In a first aspect, the valid HARQ-ACK is reported in the second slot based at least in part on a determination that the second slot occurs after the first slot.

In a second aspect, alone or in combination with the first aspect, the valid HARQ-ACK is an ACK when the PDSCH communication is successfully decoded.

In a third aspect, alone or in combination with one or more of the first and second aspects, the valid HARQ-ACK is a NACK when the PDSCH communication is not successfully decoded.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the NACK is reported in the second slot based at least in part on a determination that the second slot occurs before the first slot.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the HARQ-ACK information is generated according to a HARQ-ACK codebook that is semi-statically configured.

As shown in <FIG>, in some aspects, process <NUM> may include setting a value in HARQ-ACK information to indicate a valid HARQ-ACK, corresponding to a PDSCH communication, or a NACK based at least in part on a PDSCH-to-HARQ feedback timing value associated with the PDSCH communication (block <NUM>). For example, the UE (e.g., using controller/processor <NUM> and/or the like) may set a value in HARQ-ACK information to indicate a valid HARQ-ACK, corresponding to a PDSCH communication, or a NACK based at least in part on a PDSCH-to-HARQ feedback timing value associated with the PDSCH communication, as described above in connection with <FIG>.

As further shown in <FIG>, in some aspects, process <NUM> may include transmitting the value in the HARQ-ACK information (block <NUM>). For example, the UE (e.g., using controller/processor <NUM>, transmit processor <NUM>, TX MIMO processor <NUM>, MOD <NUM>, antenna <NUM>, and/or the like) may transmit the value in the HARQ-ACK information, as described above in connection with <FIG>.

In a first aspect, the PDSCH communication is included in multiple downlink association sets.

In a second aspect, alone or in combination with the first aspect, HARQ-ACK information for different downlink association sets is to be reported in different slots.

In a third aspect, alone or in combination with one or more of the first and second aspects, the value is set to indicate the valid HARQ-ACK if the HARQ-ACK information is to be transmitted in a slot indicated by the PDSCH-to-HARQ feedback timing value or a later slot.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the valid HARQ-ACK is an ACK when the PDSCH communication is successfully decoded.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the valid HARQ-ACK is a NACK when the PDSCH communication is not successfully decoded.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the value is set to indicate the NACK if the HARQ-ACK information is to be transmitted in a slot that is earlier than a slot indicated by the PDSCH-to-HARQ feedback timing value.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the HARQ-ACK information is transmitted according to a HARQ-ACK codebook that is semi-statically configured.

<FIG> is a diagram illustrating an example process <NUM> performed, for example, by a base station, in accordance with various aspects of the present disclosure. Example process <NUM> is an example where a base station (e.g., base station <NUM> and/or the like) performs operations associated with HARQ-ACK reporting for downlink communications included in multiple downlink association sets.

As shown in <FIG>, in some aspects, process <NUM> may include receiving a NACK in HARQ-ACK information, wherein the NACK corresponds to a PDSCH communication included in multiple downlink association sets (block <NUM>). For example, the base station (e.g., using antenna <NUM>, DEMOD <NUM>, MIMO detector <NUM>, receive processor <NUM>, controller/processor <NUM>, and/or the like) may receive a NACK in HARQ-ACK information, as described above in connection with <FIG>. In some aspects, the NACK corresponds to a PDSCH communication included in multiple downlink association sets.

As further shown in <FIG>, in some aspects, process <NUM> may include determining a first slot indicated by a PDSCH-to-HARQ feedback timing value associated with the PDSCH communication (block <NUM>). For example, the base station (e.g., using controller/processor <NUM> and/or the like) may determine a first slot indicated by a PDSCH-to-HARQ feedback timing value associated with the PDSCH communication, as described above in connection with <FIG>.

As further shown in <FIG>, in some aspects, process <NUM> may include selectively triggering retransmission of the PDSCH communication based at least in part on a timing of a second slot, in which the HARQ-ACK information is received, relative to the first slot (block <NUM>). For example, the base station (e.g., using controller/processor <NUM>, transmit processor <NUM>, TX MIMO processor <NUM>, MOD <NUM>, antenna <NUM>, and/or the like) may selectively trigger retransmission of the PDSCH communication based at least in part on a timing of a second slot, in which the HARQ-ACK information is received, relative to the first slot, as described above in connection with <FIG>.

In a first aspect, the retransmission is triggered when the second slot is a same slot as the first slot or the second slot occurs after the first slot.

In a second aspect, alone or in combination with the first aspect, the retransmission is not triggered when the second slot occurs before the first slot.

In a third aspect, alone or in combination with one or more of the first and second aspects, the HARQ-ACK information is received according to a HARQ-ACK codebook that is semi-statically configured.

As shown in <FIG>, in some aspects, process <NUM> may include determining that a PDSCH communication, to be scheduled by the base station, is associated with a plurality of downlink association sets corresponding to a plurality of PDSCH-to-HARQ feedback timing values that each indicate a different slot for reporting HARQ-ACK information for a downlink association set of the plurality of downlink association sets (block <NUM>). For example, the base station (e.g., using controller/processor <NUM> and/or the like) may determine that a PDSCH communication, to be scheduled by the base station, is associated with a plurality of downlink association sets corresponding to a plurality of PDSCH-to-HARQ feedback timing values that each indicate a different slot for reporting HARQ-ACK information for a downlink association set of the plurality of downlink association sets, as described above in connection with <FIG>.

As further shown in <FIG>, in some aspects, process <NUM> may include determining a minimum PDSCH-to-HARQ feedback timing value of the plurality of PDSCH-to-HARQ feedback timing values (block <NUM>). For example, the base station (e.g., using controller/processor <NUM> and/or the like) may determine a minimum PDSCH-to-HARQ feedback timing value of the plurality of PDSCH-to-HARQ feedback timing values, as described above in connection with <FIG>.

As further shown in <FIG>, in some aspects, process <NUM> may include signaling, to a UE, the minimum PDSCH-to-HARQ feedback timing value in association with scheduling the PDSCH communication (block <NUM>). For example, the base station (e.g., using controller/processor <NUM>, transmit processor <NUM>, TX MIMO processor <NUM>, MOD <NUM>, antenna <NUM>, and/or the like) may signal, to a UE, the minimum PDSCH-to-HARQ feedback timing value in association with scheduling the PDSCH communication, as described above in connection with <FIG>.

In a first aspect, a PDSCH-to-HARQ feedback timing value other than the minimum PDSCH-to-HARQ feedback timing value is prevented from being signaled to the UE.

In a second aspect, alone or in combination with the first aspect, the HARQ-ACK information is received according to a HARQ-ACK codebook that is semi-statically configured.

No element, act, or instruction used herein should be construed as critical or essential unless explicitly described as such. Also, as used herein, the articles "a" and "an" are intended to include one or more items, and may be used interchangeably with "one or more. " Furthermore, as used herein, the terms "set" and "group" are intended to include one or more items (e.g., related items, unrelated items, a combination of related and unrelated items, and/or the like), and may be used interchangeably with "one or more. " Where only one item is intended, the term "only one" or similar language is used. Also, as used herein, the terms "has," "have," "having," and/or the like are intended to be open-ended terms. Further, the phrase "based on" is intended to mean "based, at least in part, on" unless explicitly stated otherwise.

Claim 1:
A method (<NUM>) of wireless communication performed by a user equipment, UE, configured to operate in a 3GPP system, comprising:
determining (<NUM>) that a received physical downlink shared channel, PDSCH, communication is included in multiple downlink association sets, wherein hybrid automatic repeat request acknowledgement, HARQ-ACK, information for different downlink association sets is to be reported in different slots;
reporting (<NUM>) a valid HARQ-ACK in a first slot indicated by a PDSCH-to-HARQ feedback timing value associated with the PDSCH communication; and
selectively (<NUM>) reporting the valid HARQ-ACK, corresponding to the PDSCH communication, or a negative acknowledgement, NACK, in a second slot based at least in part on whether the second slot is a same slot as the first slot, occurs before the first slot or after the first slot, wherein the second slot is to be used for reporting HARQ-ACK information associated with a downlink association set of the multiple downlink association sets;
receiving a retransmission of the PDSCH communication only when the value of the valid HARQ-ACK is set to NACK;
wherein the selectively reporting comprises:
reporting the valid HARQ-ACK in the second slot based at least in part on a determination that the second slot is the same slot as the first slot or occurs after the first slot, wherein the valid HARQ-ACK is an ACK when the PDSCH communication is successfully decoded, or wherein the valid HARQ-ACK is a NACK when the PDSCH communication is not successfully decoded; and
reporting the NACK in the second slot based at least in part on a determination that the second slot occurs before the first slot.