Patent Description:
<CIT> relates to methods and apparatus for semi-persistent scheduling uplink and/or downlink transmissions including a UE receiving signaling configuring the UE with a first subframe configuration, determining a reference subframe configuration for downlink hybrid automatic repeat request (HARQ) operation.

The invention is defined in independent claims <NUM> and <NUM>.

Some UEs may be considered Internet-of Things (IoT) devices, and/or may be implemented as may be implemented as NB-IoT (narrowband internet of things) devices.

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 providing acknowledgement/negative acknowledgement (ACK/NACK) feedback for downlink semi-persistent scheduling (SPS) with sub-slot periodicity, 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>, 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> may include means for receiving a configuration that indicates a first sub-slot periodicity for downlink semi-persistent scheduling (SPS); means for receiving a plurality of transmissions according to the first sub-slot periodicity in a first slot, wherein the first sub-slot periodicity enables receiving the plurality of transmissions within a single slot; means for transmitting hybrid automatic repeat request acknowledgement (HARQ-ACK) information in a second slot, wherein the second slot includes a plurality of physical uplink control channels (PUCCHs) with a second sub-slot periodicity, and wherein the HARQ-ACK information is associated with the plurality of transmissions; 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, UE <NUM> may include means for receiving a configuration that indicates a sub-slot periodicity for downlink semi-persistent scheduling (SPS); means for receiving a plurality of transmissions within a single slot according to the sub-slot periodicity; means for transmitting hybrid automatic repeat request acknowledgement (HARQ-ACK) information associated with receiving the plurality of transmissions within the single slot based at least in part on a HARQ-ACK feedback scheme associated with the downlink SPS; 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> may include means for transmitting a configuration for downlink semi-persistent scheduling (SPS) to a user equipment (UE), wherein the downlink SPS has a periodicity of less than one slot and the configuration includes a physical uplink control channel (PUCCH) configuration for hybrid automatic repeat request acknowledgement (HARQ-ACK) information; means for decoding the HARQ-ACK information, received from the UE via one or more PUCCH transmissions, based at least in part on the configuration; 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). Each subframe may have a predetermined duration (e.g., <NUM>) and may include a set of slots (e.g., <NUM>m slots per subframe are shown in <FIG>, where m is a numerology used for a transmission, such as <NUM>, <NUM>,<NUM>, <NUM>, <NUM>, and/or the like). In some aspects, a scheduling unit for the FDD may frame-based, subframe-based, slot-based, symbol-based, and/or the like.

Other examples are possible and may differ from what was described with regard to <FIG> and <FIG>.

Each resource block may cover a set to of subcarriers (e.g., <NUM> subcarriers) in one slot and may include a number of resource elements.

An interlace structure may be used for each of the downlink and uplink for FDD in certain telecommunications systems (e.g., NR). For example, Q interlaces with indices of <NUM> through Q - <NUM> may be defined, where Q may be equal to <NUM>, <NUM>, <NUM>, <NUM>, or some other value. Each interlace may include slots that are spaced apart by Q frames. In particular, interlace q may include slots q, q + Q, q + 2Q, etc., where q ∈ {<NUM>,.

<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 aspects, a plurality of PDSCH transmission may be transmitted within a single slot, as described herein.

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 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 plurality of ACK/NACKs may be transmitted via PUCCH transmission resources within a single slot, based at least in part on a number of PDSCH transmissions received in a previous slot.

<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, 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.

In some instances, a BS and a UE may communicate using semi-persistent scheduling (SPS). In such cases, for downlink SPS, a periodicity associated with downlink transmissions (e.g., a length of time between PDSCH transmissions) can be equal to or greater than a length of a slot (e.g., periodicity ≥<NUM> symbols). Furthermore, a single ACK/NACK feedback (also referred to as hybrid automatic repeater request acknowledgement (HARQ-ACK) information) associated with receiving downlink transmissions is designated to be sent per slot. For example, the BS may configure (e.g., via an SPS configuration) one PUCCH resource per slot for ACK/NACK feedback (e.g., for a one bit ACK/NACK). However, in some aspects, downlink SPS can be configured, such that the periodicity is less than the length of a slot (referred to herein as sub-slot periodicity), such that multiple downlink transmissions (e.g., PDSCH transmissions) may be transmitted (e.g., by the BS) and received (e.g., by the UE) within a same slot. As used herein, the terms ACK/NACK, ACK/NACK feedback, or the like may be used interchangeably with the terms HARQ-ACK or HARQ-ACK information. HARQ-ACK information may include an ACK or a NACK depending on whether a corresponding communication was successfully received and decoded.

Some aspects described herein enable transmission of ACK/NACK(s) for downlink SPS with sub-slot periodicity (e.g., receiving multiple downlink SPS transmissions within a single slot). In some aspects described herein, a configuration for downlink SPS is provided to a UE that indicates a configuration of PUCCH resources for the transmission of respective ACK/NACKs for received transmissions (e.g., downlink transmissions, such as PDSCH transmissions). In some aspects, the configuration of PUCCH resources may indicate that a single PUCCH resource is allocated for the ACK/NACK feedback. In such cases, the UE may multiplex respective ACK/NACKs (e.g., to create ACK/NACK feedback having a number of bits that corresponds to the number of received transmissions) and/or bundle respective ACK/NACKs (e.g., use a one bit ACK/NACK representative of whether all transmissions were received or all transmissions were not received) to generate the ACK/NACK feedback associated with receiving a plurality of transmissions within a single slot. In some aspects, the configuration of the PUCCH resources may allocate multiple PUCCH resources (e.g., at least two PUCCH resources), such that the ACK/NACK feedback can be transmitted with sub-slot periodicity. In such cases, the ACK/NACK feedback that is transmitted via each PUCCH resource can include respective ACK/NACKs that are multiplexed and/or bundled for groups of transmissions received within a single slot. Additionally, or alternatively, a PUCCH resource may be allocated for each transmission, such that respective ACK/NACKs can be transmitted with a same sub-slot periodicity as the received transmissions.

Accordingly, some aspects, described herein, can support ultra-reliable low latency (URLLC) traffic via downlink SPS transmissions with sub-slot periodicity by providing ACK/NACK feedback with respective ACK/NACKs for the downlink SPS transmissions. As described herein, techniques and apparatuses for providing ACK/NACK feedback decreases the latency associated with sending ACK/NACK feedback for transmissions received with sub-slot periodicity. The ACK/NACK feedback can be associated with multiple transmissions received within a single slot and can be included within one or multiple bits of a second slot, rather than being associated with a single transmission and being included within a single bit per slot, as done using previous techniques. As such, a BS may not need wait for and/or monitor multiple slots to receive ACK/NACK feedback for a plurality of transmissions sent within a single slot. As such, the BS can more quickly determine, from the ACK/NACK feedback, whether one or more retransmissions (e.g., of a hybrid automatic repeat request (HARQ) process) of the transmissions are needed relative to previous techniques. Therefore, processing resources (e.g., to monitor for an extended number of slots) and/or network resources can be conserved (e.g., by avoiding the need to drop packets and/or transmissions associated with URLLC traffic due to delays in receiving ACK/NACK feedback and/or exceeding a timing threshold associated with the URLLC traffic).

<FIG> is a diagram illustrating an example <NUM> of providing acknowledgement/negative acknowledgement (ACK/NACK) feedback for downlink semi-persistent scheduling (SPS) with sub-slot periodicity, in accordance with various aspects of the present disclosure. In example <NUM> of <FIG>, a BS <NUM> and a UE <NUM> are configured to communicate via SPS and/or dynamic scheduling. Furthermore, BS <NUM> may be capable of sending transmissions (e.g., downlink SPS transmissions via PDSCH resources) with sub-slot periodicity. Accordingly, UE <NUM> may be configured (e.g., via a configuration for SPS received from BS <NUM>) to provide ACK/NACK feedback, for the downlink SPS with sub-slot periodicity, within a single slot according to a PUCCH configuration.

As shown in <FIG>, and by reference number <NUM>, BS <NUM> determines a configuration for downlink (DL) SPS with sub-slot periodicity. The example configuration may include the sub-slot periodicity (e.g., a <NUM>-symbol periodicity, a <NUM>-symbol periodicity, and/or the like) for receiving transmissions (e.g., PDSCH transmissions). Furthermore, the configuration may include a PUCCH configuration for ACK/NACK feedback that is to be transmitted by UE <NUM> in association with receiving the transmissions. In some aspects, the PUCCH configuration may identify a number of PUCCH resources and/or a PUCCH format (e.g., PUCCH format <NUM>, PUCCH format <NUM>, PUCCH format <NUM>, PUCCH format <NUM>, PUCCH format <NUM>, and/or the like) that is to be used to transmit the ACK/NACK feedback. In some aspects, the format of the PUCCH may depend on the sub-slot periodicity of the transmissions.

In some aspects, BS <NUM> may include a bitmap in the configuration that indicates a plurality of starting locations for a plurality of PDSCH transmissions within the slot. For example, the bitmap may have a length of <NUM> (corresponding to the <NUM> symbols of the slot). As a specific example, BS <NUM> may configure a bitmap of <NUM>, which identifies three PDSCH transmissions per slot and the first PDSCH transmission starts at symbol number <NUM> (starting from symbol <NUM>), the second PDSCH transmission starts at symbol <NUM>, and the third PDSCH transmission starts at symbol <NUM>. In some aspects, BS <NUM> may dynamically indicate the length or duration (e.g., in symbols) of the PDSCH transmissions via DCI. Such a configuration may be used within and/or associated with a time division duplex (TDD) system, as all symbols may not be used for a downlink transmission in a TDD system.

In some aspects, BS <NUM> may identify, via the configuration, which scheme is to be used for the ACK/NACK feedback. For example, the scheme (e.g., an ACK/NACK feedback scheme) may correspond to whether to multiplex or bundle the ACK/NACK feedback, whether the ACK/NACK feedback is to be transmitted via one or multiple PUCCH resources, and/or the like. In some aspects, the scheme is semi-statically configured (e.g., via RRC signaling) or dynamically signaled (e.g., via DCI, such as a DCI that activates SPS or includes SPS activation).

In some aspects, the configuration may indicate timing associated with sending the ACK/NACK feedback for received transmissions. For example, the configuration may include one or more of timings, K0, K1, and K2 (which may be referred to generally as a "K timing" and collectively herein as "K timings"), that are associated with various times or moments of a communication (e.g., a URLLC communication) between BS <NUM> and UE <NUM>. For example, K0 refers to a timing between a downlink resource grant on a physical downlink control channel (PDCCH) and a downlink data transmission on a physical downlink shared channel (PDSCH), K1 refers to timing between a downlink data transmission on the PDSCH and an uplink acknowledgement/negative acknowledgement (ACK/NACK) on a physical uplink control channel (PUCCH), and K2 refers to timing between an uplink resource grant on the PDCCH and an uplink data transmission on the PUCCH. Accordingly, as described herein, UE <NUM> may use the K1 timing to determine when the ACK/NACK feedback is to be transmitted to BS <NUM> and/or which PUCCH resource (and/or corresponding starting symbol) is to be used to transmit the ACK/NACK feedback.

BS <NUM> may configure one PUCCH resource to carry M bits, where M is the number of downlink SPS PDSCH transmissions per slot. In such cases, if M><NUM>, BS <NUM> may configure a PUCCH resource with PUCCH format <NUM>, PUCCH format <NUM>, or PUCCH format <NUM> (e.g., for ACK/NACK feedback that is greater than two bits). Furthermore, if M≤<NUM>, BS <NUM> may configure a PUCCH resource with PUCCH format <NUM> or PUCCH format <NUM> (for one bit or two bit ACK/NACK). Additionally, or alternatively, BS <NUM> may configure two or more PUCCH resources per slot. Such a configuration may include a frequency, time, and/or spatial domain allocation of the PUCCH resources and corresponding PUCCH formats. In some aspects, BS <NUM> may use DCI (e.g., DCI that activates SPS or includes SPS activation) to signal a time-domain gap between the two PUCCH resources. In some aspects, BS <NUM> may configure M PUCCH resources per slot, where M is the number of downlink SPS PDSCH transmissions per slot. In such cases, the M PUCCH resources may or may not be uniformly spaced in time.

As further shown in <FIG>, and by reference number <NUM>, BS <NUM> transmits the configuration for the downlink SPS to UE <NUM>. In some aspects, the configuration can by semi-statically transmitted (e.g., periodically or in response to a particular event) and/or dynamically transmitted (e.g., per slot, per transmission, per set of transmissions, and/or the like). For example, the configuration may be transmitted via radio resource control (RRC) signaling, DCI (e.g., DCI that activates SPS or includes SPS activation), and/or the like.

As further shown in <FIG>, and by reference number <NUM>, BS <NUM> provides transmissions with sub-slot periodicity. For example, BS <NUM> sends multiple transmissions within a single slot, such that a period between the transmissions is less than <NUM> symbols. As an example, BS <NUM> may send seven transmissions within a slot (or per slot) with a periodicity of two symbols, two transmissions within a slot (or per slot) with a periodicity of seven symbols, and/or the like. UE <NUM> is configured to receive the transmissions with sub-slot periodicity according to the configuration for the downlink SPS. For example, UE <NUM> may monitor PDSCH resources of the slot to determine whether the transmissions are successfully or unsuccessfully received and generate corresponding ACK/NACK feedback.

As further shown in <FIG>, and by reference number <NUM>, UE <NUM> generates ACK/NACK feedback according to the configuration. In some aspects, the ACK/NACK feedback may be generated in accordance with using one PUCCH resource. Additionally, or alternatively, the ACK/NACK feedback may be generated in accordance with using multiple PUCCH resources.

In some aspects, the ACK/NACK feedback may include a plurality of bits corresponding to the number of transmissions (e.g. PDSCH transmissions) received in the slot. In such cases, each bit may correspond to an ACK/NACK (e.g., an ACK = <NUM> and a NACK = <NUM>, or vice versa). Accordingly, UE <NUM> may generate the ACK/NACK feedback by combining (or multiplexing) the respective ACK/NACKs to generate a multi-bit ACK/NACK feedback in association with the transmissions received in that slot.

In some aspects, the ACK/NACK feedback may include a single bit representative of whether all of the transmissions were received within the slot or all of the transmissions were not received within the slot. For example, if all transmissions were successfully received, the ACK/NACK feedback may include a single ACK bit and if all transmissions were not successfully received, the ACK/NACK feedback may include a single NACK bit. Accordingly, UE <NUM> may generate the ACK/NACK feedback by combining (or bundling) the respective ACK/NACKs to generate a single bit ACK/NACK feedback in association with the transmissions received in that slot.

In some aspects, the ACK/NACK feedback can be generated to include multiple sets of ACK/NACK feedback (e.g., that are configured to be transmitted via multiple PUCCH resources). Each set of ACK/NACK feedback may include one or more ACK/NACK bits. For example, for each transmission received (e.g., via the PDSCH), a corresponding ACK/NACK can be generated. In some aspects, each set of ACK/NACK feedback can be generated in association with a group of one or more received transmissions. For example, the configuration may indicate that a first set of ACK/NACK feedback is to be generated for a first group of transmissions received via a first group of PDSCH resources and a second set of ACK/NACK feedback is to be generated for a second group of transmissions received via a second group of PDSCH resources.

In some aspects, for each allocated PDSCH resource of the configuration, a corresponding PUCCH resource may be allocated for ACK/NACK feedback. For example, if seven transmissions are received in a slot, then seven ACK/NACK feedback can be generated to be sent via seven separate PUCCH resources.

In some aspects, UE <NUM> generates the ACK/NACK feedback based at least in part on one or more timeline requirements for UE <NUM> to process reception of the transmissions. For example, UE <NUM> may have a processing timeline requirement that N1 symbols (e.g., OFDM symbols) are to be between receiving a transmission via a PDSCH resource and transmitting and sending a corresponding ACK/NACK. As such, in some aspects, the configuration of the SPS and the PUCCH configuration (e.g., associated with the configuration of the SPS and/or DCI) may allocate resources of the PDSCH, for receiving the transmission, and the PUCCH, for transmitting the ACK/NACK feedback, that do not satisfy the timeline requirement. Accordingly, UE <NUM> may not be able to provide ACK/NACK feedback for all received transmissions because there may not be enough time to process receipt of the transmissions that do not satisfy the timeline requirement in order to send the ACK/NACK via the designated PUCCH resource(s). Accordingly, the ACK/NACK feedback may only represent the transmissions that are received in enough time and/or that satisfy the timeline requirement N1 of UE <NUM>. In such cases, ACK/NACKs for transmissions that are received late, or without enough time to be processed and/or included within ACK/NACK feedback, may be designated as NACKs (or not successfully received). Additionally, or alternatively, the ACK/NACK feedback can include a bundled ACK/NACK for the transmissions that satisfied the timeline requirement. In some aspects, the bundled ACK/NACK may be multiplexed with dynamically scheduled ACK/NACK feedback. In some aspects, when at least one of the transmissions associated with SPS does not satisfy the time line requirement, the ACK/NACK feedback for the SPS transmissions may be dropped. Additionally, or alternatively, when at least one of the transmissions associated with SPS does not satisfy the time line requirement, all ACK/NACK feedback for that slot can be dropped, including any dynamically scheduled ACK/NACKs.

As further shown in <FIG>, and by reference number <NUM>, UE <NUM> sends the ACK/NACK feedback associated with the transmissions. The ACK/NACK feedback may be transmitted via one or more PUCCH resources in a slot that is subsequent to the slot that included the transmissions. The second slot may indicated via a K1 timing indicated in DCI provided by BS <NUM>.

The ACK/NACK feedback may be transmitted according to a PUCCH configuration received in association with the configuration of the downlink SPS. Additionally, or alternatively, the ACK/NACK feedback may be transmitted according to a PUCCH resource indicator (sometimes referred to as an ACK/NACK resource indicator (ARI)) of DCI dynamically received via a PDCCH which activates the downlink SPS transmission. In some aspects, the ACK/NACK feedback can be transmitted with sub-slot periodicity, such that multiple sets of ACK/NACK feedback are transmitted within a single slot. The sub-slot periodicity, associated with UE <NUM> transmitting the ACK/NACK feedback, may be the same or different than the sub-slot periodicity of UE <NUM> receiving the transmissions.

As further shown in <FIG>, and by reference number <NUM>, BS <NUM> decodes the ACK/NACK feedback according to the configuration. In some aspects, BS <NUM> further decodes the ACK/NACK feedback according to DCI. As such, BS <NUM> may be configured to decode the ACK/NACK feedback based at least in part on the PUCCH format associated with ACK/NACK feedback. For example, BS <NUM> may be configured to decode one bit ACK/NACK feedback or multiple bit ACK/NACK feedback (e.g., a two bit ACK/NACK feedback, a seven bit ACK/NACK feedback, and/or the like). Furthermore, in some aspects, BS <NUM> may be configured to decode multiple sets of ACK/NACK feedback within a same slot and/or that is received via multiple PUCCH resources of the same slot. For example, BS <NUM> may monitor a first set of PUCCH resources for a first set of ACK/NACK feedback and a second set of PUCCH resources for a second set of ACK/NACK feedback. In such cases, the first and second sets of ACK/NACK feedback may be respective multiplexed ACK/NACKs or a bundled ACK/NACK associated with first and second groups of transmissions, according to the configuration of the downlink SPS.

In some aspects, BS <NUM> may determine a HARQ process identifier (ID) associated with each downlink SPS transmission. In some aspects, the HARQ process ID may be determined based at least in part on a starting symbol number of a PDSCH transmission. For example, the HARQ process ID for a downlink SPS transmission may be determined based at least in part on a starting symbol number for that downlink SPS transmission. In previous techniques, the HARQ process identifier may be based at least in part on the slot index associated with transmissions scheduled via SPS. However, because SPS can have sub-slot periodicity, some aspects described herein may determine the HARQ process ID based at least in part on a symbol index within a slot. For example, the HARQ process ID can be based at least in part on the current symbol number, periodicity (in symbols), and the number of HARQ processes. The following is one example technique to find the HARQ process ID: <MAT>.

The current symbol number may be based at least in part on the subframe number (SFN), a number of slots per frame, a number of symbols per slot, the slot number in the frame, the number of symbols per slot and the symbol number in the slot. For example, the following may be an example of determining the current symbol number: <MAT> where the number of slots per frame and the number of symbols per slot refer to the number of consecutive slots per frame and the number of consecutive symbols per slot.

Accordingly, example <NUM> of <FIG> enables ACK/NACK feedback to be generated and transmitted for downlink SPS with sub-slot periodicity. As such, latency associated with feeding back ACK/NACKs associated with transmissions received within a same slot can be reduced by generating ACK/NACK feedback and transmitting the ACK/NACK feedback within a single second slot. Therefore, it may not be necessary to send multiple ACK/NACKs across multiple second slots (which increases latency), as performed in previous techniques that use only one PUCCH resource that is not configured for sub-slot periodicity.

<FIG> is a diagram illustrating an example <NUM> of providing acknowledgement/negative acknowledgement (ACK/NACK) feedback for downlink semi-persistent scheduling (SPS) with sub-slot periodicity, in accordance with various aspects of the present disclosure. <FIG> shows a first example <NUM> and a second example <NUM>.

In the first example <NUM> of <FIG>, a first slot (slot n, where n is a slot number) includes a plurality of PDSCH transmissions (shown as seven PDSCH transmissions) and a second slot (slot n + K1) includes a PUCCH resource (PUCCH Resource <NUM>) for transmitting ACK/NACK feedback associated with the PDSCH transmissions.

As shown in <FIG>, the first slot includes seven SPS PDSCH transmissions. According to some aspects, UE <NUM> may multiplex all ACK/NACKs for the seven PDSCH transmissions to generate the ACK/NACK feedback. As such, as shown by the first example <NUM>, the ACK/NACK feedback may include seven bits and be transmitted in a PUCCH resource (PUCCH Resource <NUM>). In some aspects, PUCCH Resource <NUM> may be included within one or more symbols of the second slot.

In some aspects, PUCCH Resource <NUM> is identified in the configuration for the downlink SPS. Additionally, or alternatively, the DCI may signal timing (e.g., a K1 timing) to identify timing between the first slot and the second slot. In some aspects, dynamically scheduled PDSCH transmissions may be included within the first slot in addition to the SPS PDSCH transmissions. In such cases, PUCCH Resource <NUM> may be identified by a PUCCH resource indicator in DCI via a PDCCH resource carrying a dynamically scheduled downlink grant. Accordingly, in some aspects, UE <NUM> may multiplex the respective ACK/NACKs associated with the SPS PDSCH transmissions and ACK/NACKs associated with dynamically scheduled PDSCH resources to generate ACK/NACK feedback. Accordingly, the multiplexed ACK/NACK feedback can be sent via the identified PUCCH Resource <NUM>. In some aspects, UE <NUM> may further multiplex the multiple ACK/NACK bits associated with the SPS PDSCH transmissions and ACK/NACKs associated with dynamically scheduled PDSCH resources to generate one combined ACK/NACK feedback. Accordingly, this multiplexed ACK/NACK feedback can be associated with both downlink SPS PDSCH transmissions and dynamically scheduled PDSCH transmissions and be sent via the PUCCH resource associated with the dynamically scheduled PDSCH. For example, the PDCCH associated with the dynamically scheduled PDSCHs may include a PUCCH resource indicator field that indicates the PUCCH resource to transmit the multiplexed ACK/NACK feedback.

Accordingly, the first example <NUM> can enable individual HARQ retransmissions for respective PDSCH transmissions that are indicated as not received by the ACK/NACK feedback. While the first example <NUM> of <FIG> may enable an indication of whether each individual PDSCH transmission was successfully received, this results in more than one bit of PUCCH resources to be consumed. In some aspects, as described herein, a one bit ACK/NACK associated with the received PDSCH transmissions can be generated by UE <NUM>.

As shown by second example <NUM> of <FIG>, although some techniques and apparatuses described herein support ACK/NACK for downlink SPS with a sub-slot periodicity, these techniques and apparatuses can also apply to a scenario with mixed numerology, such as where one uplink slot has a length equal to multiple downlink slots (e.g., two downlink slots, four downlink slots, and/or the like). In this case, if the periodicity of downlink SPS is one downlink slot, then this is equivalent to a periodicity one half (<NUM>/<NUM>) of the uplink slot, as shown (or one fourth (<NUM>/<NUM>) of the uplink slot when one uplink slot is the length of four downlink slots). This scenario can be viewed as a downlink SPS with sub-slot periodicity of an uplink slot (e.g., sub-uplink-slot periodicity), but with a periodicity of one downlink slot (e.g., a downlink-slot periodicity). In this case, multiple downlink SPS transmissions may occurr in respective downlink slots, but ACK/NACK feedback for these multiple downlink SPS transmissions may be transmitted in the same uplink slot. Thus, techniques described herein extend to cover this case (e.g., multiplexing all ACK/NACKs and transmitting those ACK/NACKs in the same PUCCH resource in the uplink slot).

<FIG> is a diagram illustrating an example <NUM> of providing acknowledgement/negative acknowledgement (ACK/NACK) feedback for downlink semi-persistent scheduling (SPS) with sub-slot periodicity, in accordance with various aspects of the present disclosure. In example <NUM> of <FIG>, a first slot (slot n, where n is a slot number) includes a plurality of PDSCH transmissions (shown as seven PDSCH transmissions) and a second slot (slot n + K1) includes a PUCCH resource (PUCCH Resource <NUM>) for transmitting ACK/NACK feedback associated with the PDSCH transmissions.

As shown in <FIG>, the first slot includes seven SPS PDSCH transmissions. According to some aspects, UE <NUM> may bundle all ACK/NACKs for the seven PDSCH transmissions to generate the ACK/NACK feedback by performing an AND operation on the respective ACK/NACKs for the seven PDSCH transmissions. As such, as shown by example <NUM>, the ACK/NACK feedback may include one bit and be transmitted in PUCCH Resource <NUM>. For example, the one bit ACK/NACK may be a <NUM> if any of the PDSCH transmissions are not received and a <NUM> if all of the PDSCH transmissions are received (or vice versa).

In some aspects, PUCCH Resource <NUM> is identified in the configuration for the downlink SPS. Additionally, or alternatively, the DCI may signal timing (e.g., a K1 timing) to identify timing between the first slot and the second slot. In some aspects, dynamically scheduled PDSCH transmissions may be included within the first slot in addition to the SPS PDSCH transmissions. In such cases, PUCCH Resource <NUM> may be identified by a PUCCH resource indicator in DCI via a PDCCH resource carrying a dynamically scheduled downlink grant. Accordingly, in some aspects, UE <NUM> may multiplex the one bit ACK/NACK feedback (e.g., representative of receipt of all PDSCH transmissions or non-receipt all PDSCH transmissions) associated with the SPS PDSCH transmissions and ACK/NACKs associated with dynamically scheduled PDSCH resources to generate ACK/NACK feedback. Accordingly, this multiplexed ACK/NACK feedback can be associated with both downlink SPS PDSCH transmissions and dynamically scheduled PDSCH transmissions and be sent via the PUCCH Resource associated with the dynamically scheduled PDSCH.

While example <NUM> of <FIG> may conserve PUCCH resources (e.g., by only using a one bit ACK/NACK feedback), example <NUM> does not provide a clear indication of whether each individual PDSCH transmission was successfully received because the ACK/NACK feedback indicates all PDSCH transmissions were received or none of the PDSCH transmissions were received (even though some of them might have been successfully received). As such, additional network resources may be consumed, as a HARQ retransmission may need to be performed for all of the PDSCH transmissions.

<FIG> includes diagrams illustrating examples <NUM> and <NUM> for providing acknowledgement/negative acknowledgement (ACK/NACK) feedback for downlink semi-persistent scheduling (SPS) with sub-slot periodicity, in accordance with various aspects of the present disclosure. In example <NUM> of <FIG>, a first slot (slot n, where n is a slot number) includes a plurality of PDSCH transmissions (shown as SPS PDSCH <NUM> and SPS PDSCH <NUM>) and a second slot (slot n + K1) includes a plurality of PUCCH resources (PUCCH Resource <NUM> and PUCCH Resource <NUM>) for transmitting ACK/NACK feedback associated with the PDSCH transmissions. As shown in example <NUM>, there is a seven symbol periodicity between SPS PDSCH <NUM> and SPS PDSCH <NUM> and SPS PDSCH <NUM> is received subsequent to SPS PDSCH <NUM>.

In some aspects, PUCCH Resource <NUM> and PUCCH Resource <NUM> are identified in the configuration for the downlink SPS. Additionally, or alternatively, the DCI may signal timing (e.g., a K1 timing) and/or a PUCCH resource ID (e.g., via a PUCCH resource indicator) to identify timing between the first slot and the second slot and/or PUCCH Resource <NUM> and/or PUCCH Resource <NUM>.

In some aspects, in example <NUM>, UE <NUM> may generate ACK/NACK feedback (ACK/NACK <NUM> and ACK/NACK <NUM>) for SPS PDSCH <NUM> and SPS PDSCH <NUM>, respectively. As shown, ACK/NACK <NUM> is transmitted subsequent to ACK/NACK <NUM>. However, in some aspects, PUCCH Resource <NUM> and PUCCH Resource <NUM> may not be uniformly periodic. In other words, the number of symbols between PUCCH Resource <NUM> and PUCCH Resource <NUM> may be different from the number of symbols contained in half of the slot. For example, a number of symbols (e.g., a gap) between two PUCCH resources may be different from the seven symbol periodicity shown for receiving SPS PDSCH <NUM> and SPS PDSCH <NUM>. As shown PUCCH Resource <NUM> and PUCCH Resource <NUM> are allocated in different symbols.

In example <NUM> of <FIG>, a first slot (slot n, where n is a slot number) includes a plurality of PDSCH transmissions (shown as seven SPS PDSCH transmissions) and a second slot (slot n + K1) includes a plurality of PUCCH resources (PUCCH Resource <NUM> and PUCCH Resource <NUM>) for transmitting ACK/NACK feedback associated with the PDSCH transmissions. As shown, there is a two-symbol periodicity between SPS PDSCH <NUM> and SPS PDSCH <NUM>. As further shown in example <NUM>, four of the seven PDSCH transmissions are configured to be in Group A and the remaining three PDSCH transmissions are configured to be in Group B. Other combinations of groupings are possible (e.g., five PDSCH transmissions and two PDSCH transmissions, six PDSCH transmissions and one PDSCH transmission, and/or the like). According to some aspects, the grouping does not change from slot to slot, as the grouping is defined according the configuration for downlink SPS.

In some aspects, the DCI may signal a slot number and/or a symbol number of a first PDSCH transmission. Furthermore, the DCI may include timing (e.g., a K1 timing) and/or a PUCCH resource ID (e.g., via a PUCCH resource indicator) to identify timing between the first slot and the second slot and/or PUCCH Resource <NUM> and/or PUCCH Resource <NUM>. Additionally, or alternatively, PUCCH Resource <NUM> and PUCCH Resource <NUM> may be identified in the configuration for the downlink SPS.

In example <NUM>, UE <NUM> may identify which group PDSCH transmissions are in and combine all ACK/NACKs for those transmissions to generate ACK/NACK feedback for that group. As shown, UE <NUM> may generate first ACK/NACK feedback (ACK/NACK <NUM>) for Group A and second ACK/NACK feedback (ACK/NACK <NUM>) for Group B. Accordingly, ACK/NACK <NUM> may include multiplexed ACK/NACK feedback (e.g., a four bit ACK/NACK with individual ACK/NACKs associated with each PDSCH transmission) or a bundled ACK/NACK feedback (e.g., a one bit ACK/NACK representative of whether all four PDSCH transmissions were received (ACK) or not received (NACK)). Similarly, ACK/NACK <NUM> may include multiplexed ACK/NACK feedback (e.g., a three bit ACK/NACK with individual ACK/NACKs associated with each PDSCH transmission) or a bundled ACK/NACK feedback (e.g., a one bit ACK/NACK representative of whether all three PDSCH transmissions were received (ACK) or not received (NACK)). In some aspects, ACK/NACK feedback for Group A can be transmitted via on PUCCH Resource <NUM> and ACK/NACK feedback for Group B can be transmitted via PUCCH Resource <NUM> in the next slot.

As a specific example, a first PDSCH transmission of the first slot is received via PDSCH resources of Group B (e.g., in symbol <NUM> of slot n) and the DCI may indicate that the PUCCH resource for ACK/NACK feedback is PUCCH Resource <NUM> in the second slot (e.g., by DCI including K1 timing). In such an example, UE <NUM> may multiplex ACK/NACKs to generate ACK/NACK feedback corresponding to the first PDSCH transmission and all subsequent PDSCH transmissions in Group B (e.g., a PDSCH transmission in symbol <NUM> of slot n) and transmit the ACK/NACK feedback via PUCCH Resource <NUM>. Accordingly, in a next slot (slot n +<NUM>), UE <NUM> may multiplex the ACK/NACKs for all PDSCH transmissions in group A to generate ACK/NACK feedback and transmit that ACK/NACK feedback on the next PUCCH resource (i.e., PUCCH Resource <NUM> in slot n+K1). As such, ACK/NACK feedback for subsequent groups of PDSCH transmissions are transmitted using subsequent PUCCH resources. In some aspects, the group of PDSCHs and the corresponding ACK/NACK feedback may happen within the same slot. In the above example, if K1=<NUM> slot, then the ACK/NACKs for all PDSCH transmissions in group A in slot n+<NUM> will be transmitted on the PUCCH resource <NUM> in slot n+<NUM>.

Accordingly, examples <NUM> and <NUM> enable sub-slot periodicity of ACK/NACK feedback for a plurality of transmissions received with sub-slot periodicity. As such, examples <NUM> and <NUM> may enable UE <NUM> to more quickly and efficiently communicate ACK/NACK feedback to BS <NUM> relative to previous techniques.

<FIG> is a diagram illustrating an example <NUM> of providing acknowledgement/negative acknowledgement (ACK/NACK) feedback for downlink semi-persistent scheduling (SPS) with sub-slot periodicity, in accordance with various aspects of the present disclosure. In example <NUM> of <FIG>, a first slot (slot n, where n is a slot number) includes a plurality of PDSCH transmissions (shown as seven SPS PDSCH transmissions) and a second slot (slot n + K1) includes a plurality of PUCCH resources (shown as PUCCH Resource <NUM> to PUCCH Resource <NUM>) for transmitting ACK/NACK feedback associated with the PDSCH transmissions.

In some aspects, the configuration for downlink SPS may include a PUCCH configuration that configures a same number of PUCCH resources per slot as the number of PDSCH transmissions per slot. Additionally, or alternatively, the DCI may signal starting symbol of a first PDSCH transmission received in the first slot and a corresponding PUCCH resource to transmit ACK/NACK <NUM> in the second slot. Accordingly, UE <NUM> may generate ACK/NACK <NUM> based on whether the first PDSCH transmission was successfully received and transmit ACK/NACK <NUM> via the identified PUCCH resource. Furthermore, as shown, a subsequently received PDSCH transmission may be received and UE <NUM> may generate ACK/NACK <NUM> and transmit ACK/NACK <NUM> via a PUCCH resource subsequent to the PUCCH resource used to transmit ACK/NACK <NUM>. For example, the subsequent PUCCH resource may be calculated as previous PUCCH resource + Z symbols, where the previous PUCCH resource would be the PUCCH resource used to transmit ACK/NACK <NUM> and Z = downlink SPS periodicity. In this case, the base station <NUM> may only configure the first PUCCH resource for transmitting the first ACK NACK, and the PUCCH resources for transmitting subsequent ACK/NACKs may be determined by the UE <NUM> from the first PUCCH resource and the downlink SPS periodicity. In some aspects, the subsequent PUCCH resource may be calculated using fewer than Z symbols. In some aspects, the PDSCH and the corresponding ACK/NACKs may happen in a same slot on different symbols. For example, a first PDSCH may be transmitted on symbol <NUM> in slot n, and the corresponding ACK/NACK may be transmitted on a PUCCH resource on symbol <NUM> in the same slot. A second PDSCH may be transmitted on symbol <NUM> in slot n, and the corresponding ACK/NACK may be transmitted on a PUCCH resource on symbol <NUM> in the same slot.

Accordingly, example <NUM> may enable sub-slot periodicity of ACK/NACK feedback for a plurality of transmissions received with sub-slot periodicity. In example <NUM>, latency can be relatively minimized as a same number PUCCH resources are allocated for ACK/NACK feedback as the number PDSCH transmissions that are configured to be received per slot. Further, processing resources can be conserved by configuring the PUCCH resources to have the same periodicity as the PDSCH 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>) generates ACK/NACK feedback from transmissions received with sub-slot periodicity.

As shown in <FIG>, in some aspects, process <NUM> may include receiving a configuration that indicates a sub-slot periodicity for downlink semi-persistent scheduling (SPS) (block <NUM>). For example, the UE (e.g., using receive processor <NUM>, transmit processor <NUM>, controller/processor <NUM>, memory <NUM>, and/or the like) may receive a configuration that indicates a sub-slot periodicity for downlink SPS, as described above.

As further shown in <FIG>, in some aspects, process <NUM> may include receiving a plurality of transmissions within a single slot according to the sub-slot periodicity (block <NUM>). For example, the UE (e.g., using receive processor <NUM>, transmit processor <NUM>, controller/processor <NUM>, memory <NUM>, and/or the like) may receive a plurality of transmissions within a single slot according to the sub-slot periodicity, as described above.

As further shown in <FIG>, in some aspects, process <NUM> may include transmitting hybrid automatic repeat request acknowledgement (HARQ-ACK) information associated with receiving the plurality of transmissions within the single slot based at least in part on a HARQ-ACK feedback scheme associated with the downlink SPS (block <NUM>). For example, the UE (e.g., using receive processor <NUM>, transmit processor <NUM>, controller/processor <NUM>, memory <NUM>, and/or the like) may transmit hybrid automatic repeat request acknowledgement (HARQ-ACK) information associated with receiving the plurality of transmissions within the single slot based at least in part on a HARQ-ACK feedback scheme associated with the downlink SPS, as described above.

In a first aspect, the configuration for the downlink SPS identifies one physical uplink control channel (PUCCH) resource for the HARQ-ACK information.

In a second aspect, alone or in combination with the first aspect, the HARQ-ACK information has a number of bits corresponding to a number of physical downlink shared channel (PDSCH) transmissions received in a slot.

In a third aspect, alone or in combination with one or more of the first and second aspects, the HARQ-ACK information comprises a seven-bit multiplexed HARQ-ACK information when the sub-slot periodicity comprises a two symbol periodicity, or. In some aspects, the HARQ-ACK information comprises a two-bit multiplexed HARQ-ACK information when the sub-slot periodicity comprises a seven symbol periodicity.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the HARQ-ACK information is transmitted via a resource of a physical uplink control channel (PUCCH) based at least in part on at least one of the configuration for downlink SPS or downlink control information (DCI) that activates the downlink SPS.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the HARQ-ACK information is transmitted via a physical uplink control channel (PUCCH).

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, a first format of the PUCCH is used for a first sub-slot periodicity and a second format of the PUCCH is used for a second sub-slot periodicity. In some aspects, the first format is different from the second format.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the HARQ-ACK information comprises first HARQ-ACK information associated with the downlink SPS multiplexed with second HARQ-ACK information associated with dynamic scheduling.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, the HARQ-ACK information is transmitted via a resource of a physical uplink control channel (PUCCH) indicated by a PUCCH resource indicator of downlink control information (DCI) received via a physical downlink control channel (PDCCH) carrying a dynamic scheduling downlink grant.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the HARQ-ACK information comprises a one bit bundled HARQ-ACK information with a value representative of whether all transmissions of the plurality of transmissions are received or all transmissions of the plurality of transmissions are not received.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, when a processing timeline requirement cannot be satisfied for at least one of the plurality of transmissions, the HARQ-ACK information is transmitted for remaining transmissions, of the plurality of transmissions, that satisfy the processing timeline requirement.

In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, the HARQ-ACK information comprises a number of bits corresponding to a number of transmissions that are received, within the single slot, that satisfy the processing timeline requirement.

In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, the HARQ-ACK information comprises a one bit HARQ-ACK information with a value representative of whether all transmissions, of the plurality of transmissions, that satisfy the processing timeline requirement are received or all transmissions, of the plurality of transmissions, that satisfy the processing timeline requirement are not received.

In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, HARQ-ACK information bits of the HARQ-ACK information that are associated with the downlink SPS are dropped and ACK or NACKs of the HARQ-ACK information that are associated with dynamic scheduling are transmitted.

In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, the plurality of transmissions are scheduled via the downlink SPS and the HARQ-ACK information indicates a NACK based at least in part on a determination that the processing timeline requirement cannot be satisfied for the at least one of the plurality of transmissions. In some aspects, the HARQ-ACK information is multiplexed with HARQ-ACK information associated with dynamically scheduled transmissions.

In a fifteenth aspect, alone or in combination with one or more of the first through fourteenth aspects, the HARQ-ACK information that indicates the NACK comprises a one bit NACK.

In a sixteenth aspect, alone or in combination with one or more of the first through fifteenth aspects, the HARQ-ACK information is dropped based at least in part on the at least one of the transmissions not satisfying the processing timeline requirement.

In a seventeenth aspect, alone or in combination with one or more of the first through sixteenth aspects, a hybrid automatic repeat request (HARQ) process identifier, associated with each of the plurality transmissions, is based at least in part on a starting symbol number of a physical downlink shared channel (PDSCH) transmission.

In an eighteenth aspect, alone or in combination with one or more of the first through seventeenth aspects, the sub-slot periodicity is a sub-slot periodicity of an uplink slot.

<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>) performs providing ACK/NACK feedback associated with receiving a plurality of transmissions with sub-slot periodicity.

As shown in <FIG>, in some aspects, process <NUM> may include receiving a configuration that indicates a first sub-slot periodicity for downlink semi-persistent scheduling (SPS) (block <NUM>). For example, the UE (e.g., using receive processor <NUM>, transmit processor <NUM>, controller/processor <NUM>, memory <NUM>, and/or the like) may receive a configuration that indicates a first sub-slot periodicity for downlink semi-persistent scheduling (SPS, as described above.

As further shown in <FIG>, in some aspects, process <NUM> may include receiving a plurality of transmissions according to the first sub-slot periodicity in a first slot, wherein the first sub-slot periodicity enables receiving the plurality of transmissions within a single slot (block <NUM>). For example, the UE (e.g., using receive processor <NUM>, transmit processor <NUM>, controller/processor <NUM>, memory <NUM>, and/or the like) may receive a plurality of transmissions according to the first sub-slot periodicity in a first slot, as described above. In some aspects, the first sub-slot periodicity enables receiving the plurality of transmissions within a single slot.

As further shown in <FIG>, in some aspects, process <NUM> may include transmitting hybrid automatic repeat request acknowledgement (HARQ-ACK) information in a second slot, wherein the second slot includes a plurality of physical uplink control channels (PUCCHs) with a second sub-slot periodicity, and wherein the HARQ-ACK information is associated with the plurality of transmissions (block <NUM>). For example, the UE (e.g., using receive processor <NUM>, transmit processor <NUM>, controller/processor <NUM>, memory <NUM>, and/or the like) may transmit hybrid automatic repeat request acknowledgement (HARQ-ACK) information in a second slot, as described above. In some aspects, the second slot includes a plurality of physical uplink control channels (PUCCHs) with a second sub-slot periodicity. In some aspects, the HARQ-ACK information is associated with the plurality of transmissions.

In a first aspect, the configuration for the downlink SPS identifies a plurality of physical uplink control channel (PUCCH) resources for the HARQ-ACK information.

In a second aspect, alone or in combination with the first aspect, the HARQ-ACK information is transmitted within the second slot based at least in part on at least one of the configuration for downlink SPS or downlink control information (DCI) that activates the downlink SPS.

In a third aspect, alone or in combination with one or more of the first and second aspects, first HARQ-ACK information of the HARQ-ACK information and second HARQ-ACK information of the HARQ-ACK information are transmitted via subsequent PUCCH resources.

In a fourth aspect, alone or in combination with one or more of the first through third aspects, a number of symbols between two transmissions of the plurality of transmissions is different than a number of symbols between two sets of HARQ-ACK information included in the HARQ-ACK information.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, a first set of HARQ-ACK information of the HARQ-ACK information corresponds to a first group of the plurality of transmissions and a second set of HARQ-ACK information of the HARQ-ACK information corresponds to a second group of the plurality of transmissions. In some aspects, the first group of the plurality of transmissions does not overlap with the second group of the plurality of transmissions.

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the first set of HARQ-ACK information includes multiplexed HARQ-ACK information associated with the first group of the plurality of transmissions.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the multiplexed HARQ-ACK information is transmitted in a single physical uplink control channel (PUCCH).

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, the first set of HARQ-ACK information comprises a one bit bundled HARQ-ACK information representative of whether all transmissions of the first group of the plurality of transmissions were received.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the second set of HARQ-ACK information is transmitted via a subsequent PUCCH resource to a PUCCH resource that was used to transmit the first set of HARQ-ACK information.

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, the first sub-slot periodicity equals the second sub-slot periodicity.

In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, first HARQ-ACK information of HARQ-ACK information and second HARQ-ACK information of the HARQ-ACK information are transmitted via PUCCH resources.

In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, a hybrid automatic repeat request (HARQ) process identifier, associated with each of the plurality transmissions, is based at least in part on a starting symbol number of a physical downlink shared channel (PDSCH) transmission.

In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, the configuration comprises a bitmap that indicates a plurality of starting locations for a plurality of physical downlink shared channel (PDSCH) transmissions within a single slot.

In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, the configuration indicates a number of physical uplink control channel (PUCCH) resources per slot. In some aspects, the number of PUCCH resources corresponds to a number of downlink SPS physical downlink shared channel (PDSCH) transmissions per slot.

In a fifteenth aspect, alone or in combination with one or more of the first through fourteenth aspects, PUCCH resources of the number of PUCCH resources are not uniformly spaced in time per slot.

In a sixteenth aspect, alone or in combination with one or more of the first through fifteenth aspects, the first sub-slot periodicity is a sub-slot periodicity of an uplink slot.

<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 BS (e.g., BS <NUM>) configures downlink SPS with sub-slot periodicity and decodes ACK/NACK according to the configured downlink SPS.

As shown in <FIG>, in some aspects, process <NUM> may include transmitting a configuration for downlink semi-persistent scheduling (SPS) to a user equipment (UE), wherein the downlink SPS has a periodicity of less than one slot and the configuration includes a physical uplink control channel (PUCCH) configuration for hybrid automatic repeat request acknowledgement (HARQ-ACK) information (block <NUM>). For example, the base station (e.g., using transmit processor <NUM>, receive processor <NUM>, controller/processor <NUM>, memory <NUM>, and/or the like) may transmit a configuration for downlink SPS to a UE, as described above. In some aspects, the downlink SPS has a periodicity of less than one slot and the configuration includes a physical uplink control channel (PUCCH) configuration for hybrid automatic repeat request acknowledgement (HARQ-ACK) information.

As further shown in <FIG>, in some aspects, process <NUM> may include decoding the HARQ-ACK information, received from the UE via one or more PUCCH transmissions, based at least in part on the configuration (block <NUM>). For example, the base station (e.g., using transmit processor <NUM>, receive processor <NUM>, controller/processor <NUM>, memory <NUM>, and/or the like) may decode the HARQ-ACK information, received from the UE via one or more PUCCH transmissions, based at least in part on the configuration, as described above.

In a first aspect, the configuration comprises a bitmap that indicates a plurality of starting locations for a plurality of physical downlink shared channel (PDSCH) transmissions within a single slot.

In a second aspect, alone or in combination with the first aspect, the configuration indicates a number of physical downlink shared channel (PDSCH) transmissions within a single slot.

In a third aspect, alone or in combination with one or more of the first and second aspects, a duration of each PDSCH transmission is included within downlink control information (DCI).

In a fourth aspect, alone or in combination with one or more of the first through third aspects, the configuration includes a parameter that identifies one of a plurality of schemes for the HARQ-ACK information. In some aspects, the parameter is to be used by the UE to generate the HARQ-ACK information.

In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the configuration is semi-statically configured via radio resource control (RRC) signaling or dynamically configured via an activation of SPS within downlink control information (DCI).

In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the configuration indicates that one PUCCH resource per slot is to carry a number of bits for the HARQ-ACK information. In some aspects, the number of bits corresponds to a number of downlink SPS physical downlink shared channel (PDSCH) transmissions per slot.

In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the configuration indicates a format for the PUCCH, and the format is associated with a number of bits for the HARQ-ACK information.

In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, the configuration indicates that two PUCCH resources are assigned per slot, an allocation of each of the two PUCCH resources, and a format of the two PUCCH resources.

In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, timing between the two PUCCH resources within a slot is indicated via activation downlink control information (DCI).

In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, the configuration indicates a number of PUCCH resources per slot. In some aspects, the number of PUCCH resources corresponds to a number of downlink SPS physical downlink shared channel (PDSCH) transmissions per slot.

In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, PUCCH resources of the number of PUCCH resources are not uniformly spaced in time per slot.

In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, a hybrid automatic repeat request (HARQ) process identifier, associated with the each of the plurality of transmissions, is based at least in part on a starting symbol number of a physical downlink shared channel (PDSCH) transmission.

Even though particular combinations of features are recited in the claims and/or disclosed in the specification, these combinations are not intended to limit the disclosure of possible aspects. Although each dependent claim listed below may directly depend on only one claim, the disclosure of possible aspects includes each dependent claim in combination with every other claim in the claim set.

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. " Further, as used herein, the article "the" is intended to include one or more items referenced in connection with the article "the" and may be used interchangeably with the phrase "the 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 "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. Also, as used herein, the term "or" is intended to be inclusive when used in a series and may be used interchangeably with "and/or," unless explicitly stated otherwise (e.g., if used in combination with "either" or "only one of').

Claim 1:
A method (<NUM>) of wireless communication performed by a user equipment, UE (<NUM>), comprising:
receiving (<NUM>, <NUM>) a configuration that indicates a first sub-slot periodicity for downlink semi-persistent scheduling, SPS, such that the first sub-slot periodicity is less than <NUM> OFDM symbols;
receiving (<NUM>, <NUM>) a plurality of transmissions according to the first sub-slot periodicity in a first slot, wherein the first sub-slot periodicity enables receiving the plurality of transmissions within a single slot; and
transmitting (<NUM>, <NUM>) hybrid automatic repeat request acknowledgement, HARQ-ACK, information in a second slot, wherein the second slot includes a plurality of physical uplink control channels, PUCCHs, with a second sub-slot periodicity, and wherein the HARQ-ACK information is associated with the plurality of transmissions.