Methods and apparatus for channel state information and harq feedback for sidelink communications

Abstract

Various aspects of the present disclosure generally relate to wireless communication. In some aspects, a first user equipment (UE) can receive a sidelink communication from a second UE via a physical sidelink shared channel (PSSCH). The UE can transmit, to the second UE, hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback and channel state information (CSI) feedback on a single physical sidelink feedback channel (PSFCH) resource based at least in part on the sidelink communication via the PSSCH. Numerous other aspects are described.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This Patent Application claims priority to U.S. Nonprovisional Patent Application No. 17 / 179,210, titled “TECHNIQUES FOR CHANNEL STATE INFORMATION FEEDBACK FOR SIDELINK COMMUNICATIONS” filed on February 18, 2021, which is hereby expressly incorporated by reference herein in its entirety. TECHNICAL FIELD

[0003] Aspects of the present disclosure generally relate to wireless communication and techniques and apparatuses for channel state information (CSI) feedback for sidelink communications. BACKGROUND

[0004] Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasts. Typical wireless communication systems can employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, and / or the like). Examples of such multiple-access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and long term evolution (LTE). LTE / LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the Third Generation Partnership Project (3GPP).

[0005] A wireless network can include a number of base stations (BSs) that can support communication for a number of user equipment (UEs). A UE can communicate with a BS via the downlink and uplink. The downlink (or forward link) refers to the communication from the BS to the UE, and the uplink (or reverse link) refers to the communication from the UE to the BS. As will be described in more detail herein, a BS can be referred to as a Node B, a gNB, an access point (AP), a radio head, a transmit receive point (TRP), a new radio (NR) BS, a 5G Node B, and / or the like.

[0006] The above multiple access technologies have been adopted in various telecommunication standards to provide common protocols to enable different wireless devices to communicate on a municipal, national, regional, and even global level. NR, which can also be referred to as 5G, is a set of enhancements to the LTE mobile standard promulgated by 3GPP. NR is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using orthogonal frequency division multiplexing (OFDM) with a cyclic prefix (CP) (CP-OFDM) on the downlink (DL), using CP- OFDM and / or SC-FDM (e.g., also known as discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-s-OFDM)) for the uplink (UL), as well as promoting SUMMARY

[0007] In some aspects, a method of wireless communication performed by a first user equipment (UE) includes receiving, from a second UE, a sidelink communication via a physical sidelink shared channel (PSSCH); and transmitting, to the second UE, hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback and channel state information (CSI) feedback on a single physical sidelink feedback channel (PSFCH) resource based at least in part on the sidelink communication via the PSSCH.

[0008] In some aspects, the method includes selecting a cyclic shift value for transmitting the HARQ-ACK feedback and the CSI feedback based at least in part on a bit value associated with the HARQ-ACK feedback and a bit value associated with the CSI feedback.

[0009] In some aspects, the selection of the cyclic shift value is from a set of cyclic shift values associated with equal distances between other cyclic shift values in the set of cyclic shift values.

[0010] In some aspects, the selection of the cyclic shift value is from a set of cyclic shift values associated with unequal distances between other cyclic shift values in the set of cyclic shift values.

[0011] In some aspects, the HARQ-ACK feedback is associated with a first bit and the CSI feedback is associated with a second bit.

[0012] In some aspects, the first bit is associated with a first priority level and the second bit is associated with a second priority level.

[0013] In some aspects, the first bit is associated with a most significant bit and the second bit is associated with a least significant bit.

[0014] In some aspects, the first bit is associated with a least significant bit and the second bit is associated with a most significant bit.

[0015] In some aspects, the HARQ-ACK feedback is associated with a first bit and the CSI feedback is associated with two or more bits.

[0016] In some aspects, the sending of the CSI feedback uses two or more PSFCH resources, a same HARQ-ACK feedback is associated with each of the two or more PSFCH resources, and different CSI feedback is associated with each of the two or more PSFCH resources.

[0017] In some aspects, the sending of the HARQ-ACK feedback and the CSI feedback uses two or more PSFCH resources, a first subset of the two or more PSFCH resources is associated with the HARQ-ACK feedback, and a second subset of the two or more PSFCH resources is associated with the CSI feedback.

[0018] In some aspects, the method includes transmitting additional CSI feedback in place of the HARQ-ACK feedback based at least in part on a negative-acknowledgement (NACK) only decoding feedback configuration associated with the first UE, wherein a NACK bit is repurposed to convey the additional CSI feedback.

[0019] In some aspects, the CSI indicates one or more of a demodulation reference signal received power, a channel quality indicator or a modulation and coding scheme based at least in part on the sidelink communication received from the second UE, a redundancy version index for a retransmission of the sidelink communication, or a data rank.

[0020] In some aspects, the method includes receiving, from a base station, an indication of a quantization level of a parameter associated with the CSI feedback via radio resource control signaling or via a medium access control control element (MAC-CE).

[0021] In some aspects, the first UE is a source UE and the second UE is a relay UE.

[0022] In some aspects, the first UE is a relay UE and the second UE is a source UE.

[0023] In some aspects, the sidelink communication is a first sidelink communication, and the method further comprises receiving, from the second UE, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

[0024] In some aspects, the method comprises receiving, from a base station via a physical downlink control channel, an indication of a redundancy version index for the first UE to apply when performing a subsequent transmission to the base station, wherein the redundancy version index is applicable to the first UE or to a group of UEs including the first UE and the second UE; and performing the subsequent transmission to the base station based at least in part on the redundancy version index.

[0025] In some aspects, the method comprises transmitting, to the second UE, an indication of a redundancy version for the second UE to apply when the second UE is performing the sidelink communication with the first UE; and receiving the sidelink communication comprises receiving the sidelink communication based at least in part on the redundancy version.

[0026] In some aspects, the method comprises transmitting, to the second UE, an indication of a redundancy version for the second UE to apply when the second UE is performing the sidelink communication with the first UE; and receiving the sidelink communication comprises receiving the sidelink communication via a groupcast communication based at least in part on the redundancy version.

[0027] In some aspects, the method comprises determining aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and performing a multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

[0028] In some aspects, a method of wireless communication performed by a first UE comprises transmitting, to a second UE via a PSSCH, a sidelink communication; and receiving, from the second UE and based at least in part on the sidelink communication, HARQ-ACK feedback and CSI feedback on a single PSFCH resource.

[0029] In some aspects, the first UE is a source UE and the second UE is a relay UE; or the first UE is a relay UE and the second UE is a source UE.

[0030] In some aspects, the sidelink communication is a first sidelink communication, and the method further comprises transmitting, to the second UE, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

[0031] In some aspects, the method includes receiving, from a base station via a physical downlink control channel, an indication of a redundancy version index for the first UE to apply when performing a subsequent transmission to the base station, wherein the redundancy version index is applicable to the first UE or to a group of UEs including the first UE and the second UE; and performing the subsequent transmission to the base station based at least in part on the redundancy version index.

[0032] In some aspects, the method includes receiving, from the second UE, an indication of a redundancy version for the first UE to apply when performing the sidelink communication with the second UE; and wherein transmitting the sidelink communication includes transmitting the sidelink communication based at least in part on the redundancy version.

[0033] In some aspects, the method includes receiving, from the second UE, an indication of a redundancy version for the first UE to apply when performing the sidelink communication with the second UE; and wherein transmitting the sidelink communication includes transmitting the sidelink communication based at least in part on the redundancy version via a groupcast communication.

[0034] In some aspects, the method includes determining aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and performing a multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

[0035] In some aspects, a first UE for wireless communication includes a memory and one or more processors operatively coupled to the memory, the memory and the one or more processors configured to: receive, from a second UE, a sidelink communication via a PSSCH; and transmit, to the second UE, HARQ-ACK feedback and CSI feedback on a single PSFCH resource based at least in part on the sidelink communication via the PSSCH.

[0036] In some aspects, the memory and the one or more processors are further configured to select a cyclic shift value for transmitting the HARQ-ACK feedback and the CSI feedback based at least in part on a bit value associated with the HARQ-ACK feedback and a bit value associated with the CSI feedback.

[0037] In some aspects, the selection of the cyclic shift value is from a set of cyclic shift values associated with an equal distance between other cyclic shift values in the set of cyclic shift values.

[0038] In some aspects, the selection of the cyclic shift value is from a set of cyclic shift values associated with unequal distances between other cyclic shift values in the set of cyclic shift values.

[0039] In some aspects, the HARQ-ACK feedback is associated with a first bit and the CSI feedback is associated with a second bit.

[0040] In some aspects, the first bit is associated with a first priority level and the second bit is associated with a second priority level.

[0041] In some aspects, the first bit is associated with a most significant bit and the second bit is associated with a least significant bit.

[0042] In some aspects, the first bit is associated with a least significant bit and the second bit is associated with a most significant bit.

[0043] In some aspects, the HARQ-ACK feedback is associated with a first bit and the CSI feedback is associated with two or more bits.

[0044] In some aspects, the sending of the CSI feedback uses two or more PSFCH resources, a same HARQ-ACK feedback is associated with each of the two or more PSFCH resources, and different CSI feedback is associated with each of the two or more PSFCH resources.

[0045] In some aspects, the sending of the HARQ-ACK feedback and the CSI feedback uses two or more PSFCH resources, a first subset of the two or more PSFCH resources is associated with the HARQ-ACK feedback, and a second subset of the two or more PSFCH resources is associated with the CSI feedback.

[0046] In some aspects, the memory and the one or more processors are further configured to transmit additional CSI feedback in place of the HARQ-ACK feedback based at least in part on a NACK-only decoding feedback configuration associated with the first UE, where a NACK bit is repurposed to convey the additional CSI feedback.

[0047] In some aspects, the CSI indicates one or more of a demodulation reference signal received power, a channel quality indicator or a modulation and coding scheme based at least in part on the sidelink communication received from the second UE, a redundancy version index for a retransmission of the sidelink communication, or a data rank.

[0048] In some aspects, the one or more processors are further configured to receive, from a base station via radio resource control signaling or via a MAC-CE, an indication of a quantization level of a parameter associated with the CSI feedback.

[0049] In some aspects, the first UE is a source UE and the second UE is a relay UE.

[0050] In some aspects, the first UE is a relay UE and the second UE is a source UE.

[0051] In some aspects, the sidelink communication is a first sidelink communication and the memory and the one or more processors are further configured to receive, from the second UE, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

[0052] In some aspects, the memory and the one or more processors are further configured to receive, from a base station via a physical downlink control channel, an indication of a redundancy version index for the first UE to apply when performing a subsequent transmission to the base station, wherein the redundancy version index is applicable to the first UE or to a group of UEs including the first UE and the second UE; and perform the subsequent transmission to the base station based at least in part on the redundancy version index.

[0053] In some aspects, the memory and the one or more processors are further configured to transmit, to the second UE, an indication of a redundancy version for the second UE to apply when the second UE is performing the sidelink communication with the first UE; and wherein the memory and the one or more processors, when receiving the sidelink communication, are configured to receive the sidelink communication based at least in part on the redundancy version.

[0054] In some aspects, the memory and the one or more processors are further configured to transmit, to the second UE, an indication of a redundancy version for the second UE to apply when the second UE is performing the sidelink communication with the first UE; and wherein the memory and the one or more processors, when receiving the sidelink communication, are configured to receive the sidelink communication via a groupcast communication based at least in part on the redundancy version.

[0055] In some aspects, the memory and the one or more processors are further configured to determine aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and perform a multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

[0056] In some aspects, a first UE for wireless communication includes: a memory and one or more processors operatively coupled to the memory, the memory and the one or more processors being configured to: transmit sidelink communication to a second UE via a PSSCH; and receive HARQ-ACK feedback and CSI feedback from the second UE and at least in part based on the sidelink communication on a single PSSCH resource.

[0057] In some respects, the first UE is a source UE and the second UE is a relay UE; or the first UE is a relay UE and the second UE is a source UE.

[0058] In some respects, the sidelink communication is a first sidelink communication, and the memory and the one or more processors are configured to send a second sidelink communication to the second UE, at least in part based on the HARQ-ACK feedback and the CSI feedback.

[0059] In some aspects, the memory and the one or more processors are further configured to: receive from a base station via a physical downlink control channel an indication of a redundancy version index applied by the first UE when performing subsequent transmissions to the base station, wherein the redundancy version index applies to the first UE or to a group of UEs including the first UE and the second UE; and perform the subsequent transmissions to the base station based at least in part on the redundancy version index.

[0060] In some aspects, the memory and the one or more processors are further configured to: receive from the second UE an indication of a redundant version applied by the first UE when performing the sidelink communication with the second UE; and wherein, when transmitting the sidelink communication, the one or more processors are configured to: transmit the sidelink communication at least in part based on the redundant version.

[0061] In some aspects, the memory and the one or more processors are further configured to: receive from the second UE an indication of a redundant version applied by the first UE when performing the sidelink communication with the second UE; and wherein the memory and the one or more processors are configured to: transmit the sidelink communication via multicast communication based at least in part on the redundant version when transmitting the sidelink communication.

[0062] In some aspects, the memory and the one or more processors are further configured to: determine aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and perform multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

[0063] In some aspects, a non-transitory computer-readable medium storing a set of instructions for wireless communication includes one or more instructions that, when executed by one or more processors of a first UE, cause the first UE to: receive, from a second UE via a PSSCH, a sidelink communication; and transmit, to the second UE, HARQ-ACK feedback and CSI feedback on a PSFCH resource based at least in part on the sidelink communication via the PSSCH.

[0064] In some aspects, the one or more instructions further cause the first UE to: select a cyclic shift value for transmitting the HARQ-ACK feedback and the CSI feedback based at least in part on a bit value associated with the HARQ-ACK feedback and a bit value associated with the CSI feedback.

[0065] In some aspects, the selection of the cyclic shift value is from a set of cyclic shift values associated with equal distances between other cyclic shift values in the set of cyclic shift values.

[0066] In some aspects, the selection of the cyclic shift value is from a set of cyclic shift values associated with unequal distances between other cyclic shift values in the set of cyclic shift values.

[0067] In some aspects, the HARQ-ACK feedback is associated with a first bit and the CSI feedback is associated with a second bit.

[0068] In some aspects, the first bit is associated with a first priority level and the second bit is associated with a second priority level.

[0069] In some aspects, the first bit is associated with a most significant bit and the second bit is associated with a least significant bit.

[0070] In some aspects, the first bit is associated with a least significant bit and the second bit is associated with a most significant bit.

[0071] In some aspects, the HARQ-ACK feedback is associated with a first bit and the CSI feedback is associated with two or more bits.

[0072] In some aspects, the transmission of the CSI feedback uses two or more PSFCH resources, a same HARQ-ACK feedback is associated with each of the two or more PSFCH resources, and different CSI feedback is associated with each of the two or more PSFCH resources.

[0073] In some aspects, the sending of the HARQ-ACK feedback and the CSI feedback uses two or more PSFCH resources, a first subset of the two or more PSFCH resources being associated with the HARQ-ACK feedback and a second subset of the two or more PSFCH resources being associated with the CSI feedback.

[0074] In some aspects, the one or more instructions further cause the first UE to transmit, instead of the HARQ-ACK feedback, additional CSI feedback based at least in part on a NACK-only decoding feedback configuration associated with the first UE, wherein a NACK bit is repurposed to convey the additional CSI feedback.

[0075] In some aspects, the CSI indicates one or more of a demodulation reference signal received power, a channel quality indicator based at least in part on the sidelink communication received from the second UE, or a modulation and coding scheme, a redundancy version index for a retransmission of the sidelink communication, or a data rank.

[0076] In some aspects, the one or more instructions further cause the first UE to receive, from a base station, an indication of a quantization level of a parameter associated with the CSI feedback via radio resource control signaling or via a MAC-CE.

[0077] In some aspects, the first UE is a source UE and the second UE is a relay UE.

[0078] In some aspects, the first UE is a relay UE and the second UE is a source UE.

[0079] In some aspects, the one or more instructions further cause the first UE to receive, from the second UE, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

[0080] In some aspects, the one or more instructions further cause the first UE to receive, from a base station via a physical downlink control channel, an indication of a redundancy version index for the first UE to apply when performing a subsequent transmission to the base station, wherein the redundancy version index is applicable to the first UE or to a group of UEs including the first UE and the second UE; and perform the subsequent transmission to the base station based at least in part on the redundancy version index.

[0081] In some aspects, the one or more instructions further cause the first UE to: transmit, to the second UE, an indication of a redundancy version applied by the second UE when the second UE is performing the sidelink communication with the first UE; and wherein the one or more instructions that cause the first UE to receive the sidelink communication cause the first UE to receive the sidelink communication via a groupcast communication based at least in part on the redundancy version.

[0082] In some aspects, the one or more instructions further cause the first UE to: transmit, to the second UE, an indication of a redundancy version applied by the second UE when the second UE is performing the sidelink communication with the first UE; and wherein the one or more instructions that cause the first UE to receive the sidelink communication cause the first UE to receive the sidelink communication via a groupcast communication based at least in part on the redundancy version.

[0083] In some aspects, the one or more instructions further cause the first UE to: determine aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and perform a multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

[0084] In some aspects, a non-transitory computer-readable medium storing a set of instructions for wireless communication includes one or more instructions that, when executed by one or more processors of a first UE, cause the first UE to: transmit, to a second UE, a sidelink communication via a PSSCH; and receive, from the second UE and based at least in part on the sidelink communication, HARQ-ACK feedback and CSI feedback on a single PSFCH resource.

[0085] In some aspects, the first UE is a source UE and the second UE is a relay UE; or the first UE is a relay UE and the second UE is a source UE.

[0086] In some aspects, the one or more instructions further cause the first UE to: transmit, to the second UE, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

[0087] In some aspects, the one or more instructions further cause the first UE to: receive, from a base station via a physical downlink control channel, an indication of a redundancy version index applied by the first UE when performing a subsequent transmission to the base station, wherein the redundancy version index is applicable to the first UE or to a group of UEs including the first UE and the second UE; and perform the subsequent transmission to the base station based at least in part on the redundancy version index.

[0088] In some aspects, the one or more instructions that cause the first UE to transmit the sidelink communication further cause the first UE to: receive, from the second UE, an indication of a redundancy version for the first UE to apply when performing the sidelink communication with the second UE; and wherein the one or more instructions that cause the first UE to transmit the sidelink communication cause the first UE to transmit the sidelink communication via a groupcast communication based at least in part on the redundancy version.

[0089] In some aspects, the one or more instructions that cause the first UE to transmit the sidelink communication further cause the first UE to: receive, from the second UE, an indication of a redundancy version for the first UE to apply when performing the sidelink communication with the second UE; and wherein the one or more instructions that cause the first UE to transmit the sidelink communication cause the first UE to transmit the sidelink communication via a groupcast communication based at least in part on the redundancy version.

[0090] In some aspects, the one or more instructions that cause the first UE to transmit the sidelink communication further cause the first UE to: determine aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and perform a multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

[0091] In some aspects, a first apparatus for wireless communication includes means for receiving, from a second apparatus, a sidelink communication via a PSSCH; and means for transmitting, to the second apparatus, HARQ-ACK feedback and CSI feedback on a single PSFCH resource based at least in part on the sidelink communication via the PSSCH.

[0092] In some aspects, the apparatus includes means for selecting a cyclic shift value for transmitting the HARQ-ACK feedback and the CSI feedback based at least in part on a bit value associated with the HARQ-ACK feedback and a bit value associated with the CSI feedback.

[0093] In some aspects, the selection of the cyclic shift value is from a set of cyclic shift values associated with equal distances between other cyclic shift values in the set of cyclic shift values.

[0094] In some aspects, the selection of the cyclic shift value is from a set of cyclic shift values associated with unequal distances between other cyclic shift values in the set of cyclic shift values.

[0095] In some aspects, the HARQ-ACK feedback is associated with a first bit and the CSI feedback is associated with a second bit.

[0096] In some aspects, the first bit is associated with a first priority level and the second bit is associated with a second priority level.

[0097] In some aspects, the first bit is associated with a most significant bit and the second bit is associated with a least significant bit.

[0098] In some aspects, the first bit is associated with a least significant bit and the second bit is associated with a most significant bit.

[0099] In some aspects, the HARQ-ACK feedback is associated with a first bit and the CSI feedback is associated with two or more bits.

[0100] In some aspects, the sending of the CSI feedback uses two or more PSFCH resources, a same HARQ-ACK feedback is associated with each of the two or more PSFCH resources, and different CSI feedback is associated with each of the two or more PSFCH resources.

[0101] In some aspects, the sending of the HARQ-ACK feedback and the CSI feedback uses two or more PSFCH resources, a first subset of the two or more PSFCH resources is associated with the HARQ-ACK feedback, and a second subset of the two or more PSFCH resources is associated with the CSI feedback.

[0102] In some aspects, the apparatus comprises means for transmitting additional CSI feedback in place of the HARQ-ACK feedback based at least in part on a NACK-only decoding feedback configuration associated with the first apparatus, wherein a NACK bit is repurposed to convey the additional CSI feedback.

[0103] In some aspects, the CSI indicates one or more of a demodulation reference signal received power, a channel quality indicator based at least in part on the sidelink communication received from the second apparatus, or a modulation and coding scheme, a redundancy version index for a retransmission of the sidelink communication, or a data rank.

[0104] In some aspects, the apparatus comprises means for receiving, from a base station, an indication of a quantization level of a parameter associated with the CSI feedback via radio resource control signaling or via a MAC-CE.

[0105] In some aspects, the first apparatus is a source apparatus and the second apparatus is a relay apparatus.

[0106] In some aspects, the first apparatus is a relay apparatus and the second apparatus is a source apparatus.

[0107] In some aspects, the apparatus includes means for receiving, from the second apparatus, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

[0108] In some aspects, the apparatus includes means for receiving, from a base station via a physical downlink control channel, an indication of a redundancy version index for the first apparatus to apply when performing a subsequent transmission to the base station, wherein the redundancy version index is applicable to the first apparatus or to a group of apparatuses including the first apparatus and the second apparatus; and performing the subsequent transmission to the base station based at least in part on the redundancy version index.

[0109] In some aspects, the apparatus includes means for transmitting, to the second apparatus, an indication of a redundancy version for the second apparatus to apply when the second apparatus is performing the sidelink communication with the first apparatus; and wherein the means for receiving the sidelink communication includes means for receiving the sidelink communication based at least in part on the redundancy version.

[0110] In some aspects, the apparatus includes means for transmitting, to the second apparatus, an indication of a redundancy version for the second apparatus to apply when the second apparatus is performing the sidelink communication with the first apparatus; and wherein the means for receiving the sidelink communication includes means for receiving the sidelink communication via a groupcast communication based at least in part on the redundancy version. The means for receiving the sidelink communication includes means for receiving the sidelink communication via a groupcast communication based at least in part on the redundancy version.

[0111] In some aspects, the apparatus includes means for determining aggregated feedback information for a plurality of apparatuses, wherein the aggregated feedback information indicates CSI for the plurality of apparatuses; and means for performing a multicast transmission to the plurality of apparatuses based at least in part on the aggregated feedback information.

[0112] In some aspects, a first apparatus for wireless communication includes means for transmitting, to a second apparatus via a PSSCH, a sidelink communication; and means for receiving, from the second apparatus and based at least in part on the sidelink communication, HARQ-ACK feedback and CSI feedback on a single PSFCH resource.

[0113] In some aspects, the first apparatus is a source apparatus and the second apparatus is a relay apparatus; or the first apparatus is a relay apparatus and the second apparatus is a source apparatus.

[0114] In some aspects, the apparatus includes means for transmitting, to the second apparatus, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

[0115] In some aspects, the apparatus includes means for receiving, from a base station via a physical downlink control channel, an indication of a redundancy version index for the first apparatus to apply when performing a subsequent transmission to the base station, wherein the redundancy version index is applicable to the first apparatus or to a group of apparatuses including the first apparatus and the second apparatus; and means for performing the subsequent transmission to the base station based at least in part on the redundancy version index.

[0116] In some aspects, the apparatus includes means for receiving, from the second apparatus, an indication of a redundancy version for the first apparatus to apply when performing the sidelink communication with the second apparatus; and wherein the means for transmitting the sidelink communication includes means for transmitting the sidelink communication based at least in part on the redundancy version. The means for transmitting the sidelink communication includes means for transmitting the sidelink communication based at least in part on the redundancy version.

[0117] In some aspects, the apparatus includes means for receiving, from the second apparatus, an indication of a redundancy version for the first apparatus to apply when performing the sidelink communication with the second apparatus; and wherein the means for transmitting the sidelink communication includes means for transmitting the sidelink communication based at least in part on the redundancy version via a groupcast communication. The means for transmitting the sidelink communication includes means for transmitting the sidelink communication based at least in part on the redundancy version via a groupcast communication.

[0118] In some aspects, the apparatus includes means for determining aggregated feedback information for a plurality of apparatuses, wherein the aggregated feedback information indicates CSI for the plurality of apparatuses; and means for performing a multicast transmission to the plurality of apparatuses based at least in part on the aggregated feedback information.

[0119] Aspects generally include a method, apparatus, system, computer program product, non-transitory computer-readable medium, user equipment, base station, wireless communication device, and / or processing system as substantially described herein with reference to and as illustrated by the accompanying drawings and specification.

[0120] The features and technical advantages of examples according to this disclosure have been outlined quite extensively above to facilitate a better understanding of the following detailed description. Other features and advantages will be described below. The disclosed concepts and specific examples can be readily used as the basis for modifying or designing other structures for achieving the same purpose as this disclosure. Such equivalent structures do not depart from the scope of the appended claims. The features of the concepts disclosed herein, their organization and operation, and related advantages will be better understood from the following description when considered in conjunction with the accompanying drawings. Each drawing is provided for illustrative and descriptive purposes and not as a limitation of the definitions in the claims. Attached Figure Description

[0121] To gain a more detailed understanding of the features of this disclosure, a more specific description of the brief overview above can be obtained by referring to some of the aspects shown in the accompanying drawings. However, it should be noted that the drawings illustrate only certain typical aspects of this disclosure and should not be considered as limiting its scope, as the description may allow for other equivalent aspects. The same reference numerals in different drawings may identify the same or similar elements.

[0122] Figure 1 This is a schematic diagram illustrating an example of a wireless network according to this disclosure.

[0123] Figure 2 This is a schematic diagram illustrating an example of communication between a base station and a UE in a wireless network in accordance with this disclosure.

[0124] Figure 3 This is a schematic diagram illustrating an example of sidelink communication in accordance with this disclosure.

[0125] Figure 4 This is a schematic diagram illustrating examples of sidelink communication and access link communication in accordance with this disclosure.

[0126] Figure 5 This is a schematic diagram illustrating an example of a time-slot structure according to this disclosure.

[0127] Figure 6 This is a schematic diagram illustrating an example of a demodulation reference signal (DMRS) resource element according to this disclosure.

[0128] Figure 7 This is a schematic diagram illustrating an example of a demodulation reference signal (DMRS) mode according to this disclosure.

[0129] Figure 8 This is a schematic diagram illustrating an example of side link control information according to this disclosure.

[0130] Figure 9is a diagram illustrating an example of a physical sidelink feedback channel (PSFCH) in a slot, in accordance with the present disclosure.

[0131] Figure 10 is a diagram illustrating an example of PSFCH resource mapping, in accordance with the present disclosure.

[0132] Figure 11 is a diagram illustrating an example of a sidelink operation mode, in accordance with the present disclosure.

[0133] Figures 12-13 is a diagram illustrating an example of uplink tunneling via a relay, in accordance with the present disclosure.

[0134] Figure 14 is a diagram illustrating an example of sidelink communication, in accordance with the present disclosure.

[0135] Figure 15 is a diagram illustrating an example of a mapping between hybrid automatic repeat request-acknowledgement (HARQ-ACK) information bit values and cyclic shifts, in accordance with the present disclosure.

[0136] Figures 16-22 is a diagram illustrating an example associated with channel state information (CSI) feedback for sidelink communication, in accordance with the present disclosure.

[0137] Figures 23-24 is a diagram illustrating an example process associated with CSI feedback for sidelink communication, in accordance with the present disclosure.

[0138] Figure 25 is a block diagram of an example apparatus for wireless communication, in accordance with the present disclosure. DETAILED DESCRIPTION

[0139] Various aspects of the disclosure are now described with reference to the drawings. The various aspects of the disclosure, however, can be embodied in many different forms and should not be construed as limited to any specific structure or function presented throughout this disclosure. Rather, these aspects are provided as illustrative examples so that this disclosure will be thorough and complete, and will fully convey the scope of the disclosure to those skilled in the art. Based on the teachings herein, one skilled in the art should appreciate that the scope of the disclosure is intended to cover any aspect of the disclosure disclosed herein, whether implemented independently of or combined with any other aspect of the disclosure. For example, an apparatus can be implemented or a method can be practiced using any number of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method which is practiced using other structure, functionality, or structure and functionality in addition to or other than the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein can be embodied by one or more elements of a claim.

[0140] Several aspects of telecommunication systems will now be presented with reference to various apparatus and methods. These apparatus and methods will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, and / or the like (collectively referred to as “elements”). These elements can be implemented using hardware, software, or combinations thereof. Whether such elements are implemented as hardware or software depends on the particular application and design constraints imposed on the overall system.

[0141] It should be noted that while aspects can be described herein using terminology commonly associated with a 5G or NR radio access technology (RAT), aspects of the present disclosure can be applied to other RATs, such as a 3G RAT, a 4G RAT, and / or a RAT subsequent to 5G (e.g., 6G).

[0142] Figure 1 FIG. 1 is a diagram illustrating an example of a wireless network 100 in accordance with various aspects of the present disclosure. The wireless network 100 can be or can include elements of a 5G (NR) network and / or an LTE network, among other examples. The wireless network 100 can include a number of base stations 110 (shown as BS 110a, BS 110b, BS 110c, and BS 1 lOd) and other network entities. A base station (BS) is an entity that communicates with user equipment (UE) and can also be referred to as an NR BS, a Node B, a gNB, a 5G node B (NB), an access point, a transmit receive point (TRP), and / or the like. Each BS can provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to a coverage area of a BS and / or a BS subsystem serving the coverage area, depending on the context in which the term is used.

[0143] A BS can provide communication coverage for a macro cell, a pico cell, a femto cell, and / or other types of cell. A macro cell can cover a relatively large geographic area (e.g., several kilometers in radius) and can allow unrestricted access by UEs with service subscription. A pico cell can cover a relatively small geographic area and can allow unrestricted access by UEs with service subscription. A femto cell can cover a relatively small geographic area (e.g., a home) and can allow restricted access by UEs with service subscription, e.g., access can be restricted to UEs in the Figure 1 In the example shown, BS 110a can be a macro BS for macro cell 102a, BS 110b can be a pico BS for pico cell 102b, and BS 110c can be a femto BS for femto cell 102c. A BS can support one or multiple (e.g., three) cells. The terms “eNB,” “base station,” “NR BS,” “gNB,” “TRP,” “AP,” “Node B,” “5G NB,” and “cell” can be used interchangeably herein.

[0144] In some aspects, a cell can not necessarily be stationary, and the geographic area of the cell can move according to the location of a mobile BS. In some aspects, BSs can be interconnected to one another and / or to one or more other BSs or network nodes (not shown) in the wireless network 100 through various types of backhaul interfaces such as a direct physical connection or a virtual network, using any suitable transport network.

[0145] Wireless network 100 can also include relay stations. A relay station is an entity that can receive a transmission of data from an upstream station (e.g., a BS or a UE) and send a transmission of the data to a downstream station (e.g., a UE or a BS). A relay station can also be a UE that can relay transmissions for other UEs. In Figure 1 In the example shown, a relay BS 1 lOd can communicate with macro BS 110a and a UE 120d in order to facilitate communications between the BS 110a and UE 120d. A relay BS can also be referred to as a relay station, a relay base station, a relay, or the like.

[0146] Wireless network 100 can be a heterogeneous network that includes BSs of different types, e.g., macro BSs, pico BSs, femto BSs, relay BSs, etc. These different types of BSs can have different transmit power levels, different coverage areas, and different impacts on interference. For example, macro BSs can have a high transmit power level (e.g., 5 to 40 Watts), whereas pico BSs, femto BSs, and relay BSs can have relatively lower transmit power levels (e.g., 0.1 to 2 Watts).

[0147] A network controller 130 can couple to a set of BSs and can provide coordination and control for these BSs. Network controller 130 can be in communication with the BSs via a backhaul. The BSs can also communicate with one another, e.g., directly or indirectly via a wireless or wireline backhaul.

[0148] UEs 120 (e.g., 120a, 120b, 120c) can be dispersed throughout wireless network 100, and each UE can be stationary or mobile. A UE can also be referred to as an access terminal, a terminal, a mobile station, a subscriber unit, a station, etc. A UE can be a cellular phone (e.g., a smart phone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, a biometric sensor / device, a wearable device (smart watches, smart clothing, smart glasses, smart wrist bands, smart jewelry (e.g., smart ring, smart bracelet)), an entertainment device (e.g., a music or video device, a satellite radio), a vehicular component or sensor, a smart meter / sensor, industrial manufacturing equipment, a global positioning system device, or any other suitable device that is configured to communicate via a wireless or wired medium.

[0149] Some UEs can be considered machine-type communication (MTC) or evolved or enhanced machine-type communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, and / or location tags, that can communicate with a base station, another device (e.g., remote device), or some other entity. A wireless node can provide, for example, connectivity for or to a network (e.g., a wide area network such as Internet or a cellular network) via a wired or wireless communication link. Some UEs can be considered Internet-of-Things (IoT) devices and / or can be implemented as NB-IoT (narrowband internet of things) devices. Some UEs can be considered user equipment (UE). UE 120 can be included in a housing along with components such as processor components and / or memory components. In some aspects, the processor components and the memory components can be coupled together. For example, the processor components (e.g., one or more processors) and the memory components (e.g., a memory) can be operatively coupled, communicatively coupled, electronically coupled, electrically coupled.

[0150] In general, any number of wireless networks can be deployed in a given geographic area. Each wireless network can support a particular RAT and can operate on one or more frequencies. A RAT can also be referred to as a radio technology, an air interface, and / or the like. A frequency can also be referred to as a carrier, a frequency channel, and / or the like. In

[0151] In some aspects, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) can communicate directly using one or more sidelink channels (e.g., without using base station 110 as an intermediary to communicate with one another). For example, UE 120 can perform scheduling operations, resource selection operations, and / or other operations described elsewhere herein as being performed by base station 110. In some aspects, one or more of these devices can perform functions described elsewhere as being performed by a network entity (e.g., base station 110).

[0152] Devices of wireless network 100 can communicate using the electromagnetic spectrum, which can be subdivided, based on frequency or wavelength, into various classes, bands, channels, and so on. For example, devices of wireless network 100 can communicate using frequency bands having a first range of frequencies (FR1), which can span, for example, from 410 MHz to 7.125 GHz, and / or using frequency bands having a second range of frequencies (FR2), which can span, for example, from 24.25 GHz to 52.6 GHz. The frequencies between FR1 and FR2 are sometimes referred to as mid-band frequencies. Although a portion of FR1 is greater than 6 GHz, FR1 is often referred to as a “sub-6 GHz” frequency band. Similarly, FR2 is often referred to as a “millimeter wave” frequency band, despite being different from the extremely high frequency (EHF) band, which the International Telecommunications Union (ITU) has identified as spanning from 30 GHz to 300 GHz. Thus, unless specifically stated otherwise, the term “sub-6 GHz,” or the like, if used herein, can broadly represent frequencies less than 6 GHz, frequencies within FR1, and / or mid-band frequencies (e.g., greater than 7.125 GHz). Similarly, unless specifically stated otherwise, the term “millimeter wave,” or the like, if used herein, can broadly represent frequencies within the EHF band, frequencies within FR2, and / or mid-band frequencies (e.g., less than 24.25 GHz). It is contemplated that the frequencies included in FR1 and FR2 can be modified, and that the techniques described herein can apply to those modified frequency ranges.

[0153] As described above, there is provided Figure 1 as examples. Other examples can differ from those described. Figure 1 The described examples can differ from one another in different ways.

[0154] Figure 2 is a schematic diagram illustrating an example 200 of a base station 110 in communication with a UE 120 in a wireless network 100, in accordance with various aspects of the present disclosure. The base station 110 can be equipped with T antennas 234a through 234t, and the UE 120 can be equipped with R antennas 252a through 252r, where in general T > 1 and R > 1.

[0155] At base station 110, a transmit processor 220 can receive data from a data source 212 for one or more UEs, select one or more modulation and coding schemes (MCS) for each UE based at least in part on channel quality indicators (CQIs) received from the UE, process (e.g., encode and modulate) the data for each UE based at least in part on the MCS(s) selected for the UE, and provide data symbols for all UEs. Transmit processor 220 can also process system information (e.g., for semi-static resource partitioning information (SRPI)) and control information (e.g., CQI requests, grants, and / or upper layer signaling) and provide overhead symbols and control symbols. Transmit processor 220 can also generate reference symbols for reference signals (e.g., a cell-specific reference signal (CRS) or a DMRS) and synchronization signals (e.g., a primary synchronization signal (PSS) or a secondary synchronization signal (SSS)). A transmit (TX) multiple-input multiple-output (MIMO) processor 230 can perform spatial processing (e.g., precoding) on the data symbols, the control symbols, the overhead symbols, and / or the reference symbols, if applicable, and can provide T output symbol streams to T modulators (MODs) 232a through 232t. Each modulator 232 can process a respective output symbol stream (e.g., for OFDM) to obtain an output sample stream. Each modulator 232 can further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. The T downlink signals from modulators 232a through 232t can be transmitted via T antennas 234a through 234t, respectively.

[0156] At the UE 120, the antennas 252a through 252r can receive the downlink signals from the base station 110 and / or other base stations and can provide received signals to the demodulators (DEMODs) 254a through 254r, respectively. Each demodulator 254 can condition (e.g., filter, amplify, downconvert, and digitize) a received signal to obtain input samples. Each demodulator 254 can further process the input samples (e.g., for OFDM) to obtain received symbols. A MIMO detector 256 can obtain received symbols from all R demodulators 254a through 254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 258 can process (e.g., demodulate and decode) the detected symbols, provide decoded data for the UE 120 to a data sink 260, and provide decoded control information and system information to a controller / processor 280. The term “controller / processor” can refer to one or more controllers, one or more processors, or combinations thereof. A channel processor can determine reference signal received power (RSRP) parameters, received signal strength indicator (RSSI) parameters, reference signal received quality (RSRQ) parameters, and / or CQI parameters, among other examples. In some aspects, one or more components of UE 120 can be included in a housing 284.

[0157] The network controller 130 can include a communication unit 294, a controller / processor 290, and a memory 292. The network controller 130 can include, for example, one or more devices in a core network. The network controller 130 can communicate with the base station 110 via the communication unit 294.

[0158] An antenna (e.g., antennas 234a through 234t or antennas 252a through 252r) can include or be included within one or more antenna panels, antenna groups, sets of antenna elements, and / or antenna arrays, among other examples. An antenna panel, antenna group, set of antenna elements, and / or antenna array can include one or more antenna elements. An antenna panel, antenna group, set of antenna elements, and / or antenna array can include a set of co-planar antenna elements or a set of non-co-planar antenna elements. An antenna panel, antenna group, set of antenna elements, and / or antenna array can include antenna elements within a single housing or antenna elements within multiple housings. An antenna panel, antenna group, set of antenna elements, and / or antenna array can include one or more antenna elements coupled to one or more transmit components or receive components, such as one or more components of a transceiver 270. Figure 2 An antenna panel, antenna group, set of antenna elements, and / or antenna array can include one or more antenna elements coupled to one or more transmit components or receive components, such as one or more components of a transceiver 270.

[0159] On the uplink, at UE 120, a transmit processor 264 can receive and process data from a data source 262 and control information (e.g., for reports comprising RSRP, RSSI, RSRQ, and / or CQI) from controller / processor 280. Transmit processor 264 can also generate reference symbols for one or more reference signals. The symbols from transmit processor 264 can be precoded by a TX MIMO processor 266 if applicable, further processed by modulators 252a through 252r (e.g., for DFT-s-OFDM or CP-OFDM), and transmitted to base station 110. In some aspects, a modulator and a demodulator (e.g., MOD / DEMOD 254) of the UE 120 can be included in a modem of the UE 120. In some aspects, the UE 120 includes a transceiver. The transceiver can include any combination of antenna(s) 252, modulators and / or demodulators 254, MIMO detector 256, receive processor 258, transmit processor 264, and / or TX MIMO processor 266. The transceiver can be used by a processor (e.g., controller / processor 280) and memory 282 to perform any of the aspects of the methods described herein.

[0160] At base station 110, the uplink signals from UE 120 and other UEs can be received by antennas 234, processed by demodulators 232, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by UE 120. Receive processor 238 can provide the decoded data to a data sink 239 and to controller / processor 240 for control information. Base station 110 can include communication unit 244 and communicate to network controller 130 via communication unit 244. Base station 110 can include a scheduler 246 to schedule UEs 120 for downlink and / or uplink communications. In some aspects, a modulator and a demodulator (e.g., MOD / DEMOD 232) of the base station 110 can be included in a modem of the base station 110. In some aspects, the base station 110 includes a transceiver. The transceiver can include any combination of antenna(s) 234, modulators and / or demodulators 232, MIMO detector 236, receive processor 238, transmit processor 220, and / or TX MIMO processor 230. The transceiver can be used by a processor (e.g., controller / processor 240) and memory 242 to perform any of the aspects of the methods described herein.

[0161] Controller / processor 240 of base station 110, controller / processor 280 of UE 120, and / or Figure 2Any other components of the UE 120 can perform one or more techniques associated with CSI feedback for sidelink communications, as described in more detail elsewhere herein. For example, the controller / processor 280, and / or other components of the UE 120 can determine a set of CSI feedback values for a sidelink communication, and / or transmit a sidelink communication including the set of CSI feedback values. Figure 2 Any other components of the UE 120 can perform or direct operations of, for example, Figure 23 process 2300 of FIG. 13, Figure 24 process 2400 of FIG. 14, and / or other processes as described herein. The memories 242 and 282 can store data and program codes for the base station 110 and UE 120, respectively. In some aspects, the memory 242 and / or the memory 282 can include a non-transitory computer-readable medium storing one or more instructions (e.g., code, program code) for wireless communication. For example, the one or more instructions, when executed (e.g., directly, or after compiling, converting, and / or interpreting) by one or more processors of the base station 110 and / or the UE 120, can cause the one or more processors, the UE 120, and / or the base station 110 to perform or direct operations of, for example, Figure 23 process 2300 of FIG. 13, Figure 24 process 2400 of FIG. 14, and / or other processes as described herein. In some aspects, executing instructions can include running the instructions, converting the instructions, compiling the instructions, and / or interpreting the instructions.

[0162] In some aspects, a first UE (e.g., UE 120) includes means for receiving, from a second UE, a sidelink communication via a physical sidelink shared channel (PSSCH); and / or means for transmitting, to the second UE, hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback and channel state information (CSI) feedback on a single physical sidelink feedback channel (PSFCH) resource based at least in part on the sidelink communication via the PSSCH. The means for the first UE to perform operations described herein can include, for example, one or more of the antenna 252, the demodulator 254, the MIMO detector 256, the receive processor 258, the transmit processor 264, the TX MIMO processor 266, the modulator 254, the controller / processor 280, or the memory 282.

[0163] In some aspects, a first UE includes means for selecting a cyclic shift value for transmitting HARQ-ACK feedback and CSI feedback based at least in part on a bit value associated with the HARQ-ACK feedback and a bit value associated with the CSI feedback.

[0164] In some aspects, the first UE includes means for transmitting, based at least in part on a negative-acknowledgement (NACK) only decoding feedback configuration associated with the first UE, additional CSI feedback in place of HARQ-ACK feedback, wherein a NACK bit is repurposed to convey the additional CSI feedback.

[0165] In some aspects, the first UE includes means for receiving, from a base station, an indication of a quantization level of a parameter associated with CSI feedback via radio resource control signaling or via a medium access control control element (MAC-CE).

[0166] In some aspects, the first UE includes means for receiving, from a second UE, a second sidelink communication based at least in part on HARQ-ACK feedback and CSI feedback.

[0167] In some aspects, the first UE includes means for receiving, from a base station via a physical downlink control channel, an indication of a redundancy version index for the first UE to apply when performing a subsequent transmission to the base station, wherein the redundancy version index is applicable to the first UE or to a group of UEs including the first UE and the second UE; and / or means for performing the subsequent transmission to the base station based at least in part on the redundancy version index.

[0168] In some aspects, the first UE includes means for transmitting, to a second UE, an indication of a redundancy version for the second UE to apply when the second UE is performing a sidelink communication with the first UE; or

[0169] In some aspects, the first UE includes means for transmitting, to a second UE, an indication of a redundancy version for the second UE to apply when the second UE is performing a sidelink communication with the first UE; or

[0170] In some aspects, the first UE includes means for determining aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and / or means for performing a multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

[0171] In some aspects, the first UE (e.g., UE 120a) includes means for transmitting, to a second UE via a PSSCH, a sidelink communication; and / or means for receiving, from the second UE and based at least in part on the sidelink communication, HARQ-ACK feedback and CSI feedback on a single PSFCH resource. The means for the first UE to perform operations described herein can include, for example, one or more of antenna 252, demodulator 254, MIMO detector 256, receive processor 258, transmit processor 264, TX MIMO processor 266, modulator 254, controller / processor 280, or memory 282.

[0172] In some aspects, the first UE includes means for transmitting, to the second UE, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

[0173] In some aspects, the first UE includes means for receiving, from the base station via a physical downlink control channel, an indication of a redundancy version index for the first UE to apply when performing a subsequent transmission to the base station, wherein the redundancy version index is applicable to the first UE or to a group of UEs including the first UE and the second UE; and / or means for performing the subsequent transmission to the base station based at least in part on the redundancy version index.

[0174] In some aspects, the first UE includes means for determining aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and / or means for performing a multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

[0175] As described above, there is provided a method of wireless communication performed by a first user equipment (UE), comprising: Figure 2 By way of example. Other examples can differ from what is described. Figure 2 The described examples can be implemented in different ways.

[0176] Figure 3 FIG. 3 is a schematic diagram illustrating an example 300 of sidelink communication, in accordance with the present disclosure.

[0177] As shown in FIG. 3, a first UE 305-1 can communicate with a second UE 305-2 (and one or more other UEs 305) via one or more sidelink channels 310. The UEs 305-1 and 305-2 can communicate using the one or more sidelink channels 310 for P2P communication, D2D communication, V2X communication (e.g., which can include V2V communication, V2I communication, vehicle-to-person (V2P) communication, etc.), mesh networking, etc. In some aspects, the UEs 305 (e.g., UE 305-1 and / or UE 305-2) can include one or more other UEs described in other portions of the present disclosure, such as the UEs 120. In some aspects, the one or more sidelink channels 310 can use a PC5 interface, can operate in a high frequency band (e.g., a 5.9 GHz band), can operate on an unlicensed or shared frequency band (e.g., an NR-unlicensed (NR-U) band), etc. Additionally, or alternatively, the UEs 305 can synchronize timing of transmission time intervals (TTIs) (e.g., frames, subframes, slots, symbols, etc.) using global navigation satellite system (GNSS) timing. Figure 3 As shown in FIG. 3, a first UE 305-1 can communicate with a second UE 305-2 (and one or more other UEs 305) via one or more sidelink channels 310. The UEs 305-1 and 305-2 can communicate using the one or more sidelink channels 310 for P2P communication, D2D communication, V2X communication (e.g., which can include V2V communication, V2I communication, vehicle-to-person (V2P) communication, etc.), mesh networking, etc. In some aspects, the UEs 305 (e.g., UE 305-1 and / or UE 305-2) can include one or more other UEs described in other portions of the present disclosure, such as the UEs 120. In some aspects, the one or more sidelink channels 310 can use a PC5 interface, can operate in a high frequency band (e.g., a 5.9 GHz band), can operate on an unlicensed or shared frequency band (e.g., an NR-unlicensed (NR-U) band), etc. Additionally, or alternatively, the UEs 305 can synchronize timing of transmission time intervals (TTIs) (e.g., frames, subframes, slots, symbols, etc.) using global navigation satellite system (GNSS) timing.

[0178] Figure 3 ​As further shown, one or more sidelink channels 310 can include a physical sidelink control channel (PSCCH) 315, a PSSCH 320, and / or a PSFCH 325. The PSCCH 315 can be used to transmit control information, similar to a physical downlink control channel (PDCCH) and / or a physical uplink control channel (PUCCH) used for cellular communications with a base station 110 via an access link or access channel. The PSSCH 320 can be used to transmit data, similar to a physical downlink shared channel (PDSCH) and / or a physical uplink shared channel (PUSCH) used for cellular communications with a base station 110 via an access link or access channel.

[0179] The PSCCH 315 can carry an SCI-1 330, which can indicate various control information for the sidelink communication. The control information can include an indication of one or more resources (e.g., time resources, frequency resources, spatial resources, and / or the like) on which various types of information can be carried on the PSSCH 320, information for decoding the sidelink communication on the PSSCH 320, a quality of service (QoS) priority value, a resource reservation period, a PSSCH demodulation reference signal (DMRS) pattern, a sidelink control information (SCI) format, and a beta (b) offset for an SCI-2 335 transmitted on the PSSCH 320, a number of PSSCH DMRS ports, an MCS, and / or the like.

[0180] The information carried on the PSSCH 320 can include an SCI-2 335 and / or data 340. The SCI-2 335 can include various types of information, such as a HARQ process ID, a new data indicator (NDI) associated with the data 340, a source identifier, a destination identifier, a CSI report trigger, and / or the like. In some aspects, the UE 305 can transmit both the SCI-1 330 and the SCI-2 335. In some aspects, the UE 305 can transmit only the SCI-1 330, in which case one or more types of information that would otherwise be transmitted in the SCI-2 335 can instead be transmitted in the SCI-1 330.

[0181] The PSFCH 325 can be used to transmit sidelink feedback 345, such as HARQ feedback (e.g., acknowledgement or negative acknowledgement (ACK / NACK) information), transmit power control (TPC), a scheduling request (SR), and / or the like.

[0182] As described above, the provision of the SCI-1 330 and the SCI-2 335 can be used to provide a number of benefits. Figure 3 As an example. Other examples can differ from what is described Figure 3 in the described examples.

[0183] Figure 4is a diagram illustrating an example 400 of sidelink communications and access link communications, in accordance with the present disclosure.

[0184] As Figure 4 illustrated, Tx / Rx UE 405 and Rx / Tx UE 410 can communicate with one another via a sidelink, as described above in connection with Figure 3 FIG. 2. As further illustrated, in some sidelink modes, base station 110 can communicate with Tx / Rx UE 405 via a first access link. Additionally or alternatively, in some sidelink modes, base station 110 can communicate with Rx / Tx UE 410 via a second access link. Tx / Rx UE 405 and / or Rx / Tx UE 410 can correspond to one or more UEs described elsewhere herein, such as UE 120 of Figure 1 FIG. 1. Thus, a direct link between UEs 120 (e.g., via a PC5 interface) can be referred to as a sidelink, and a direct link between a base station 110 and a UE 120 (e.g., via a Uu interface) can be referred to as an access link. Sidelink communications can be transmitted via a sidelink, and access link communications can be transmitted via an access link. Access link communications can be downlink communications (from a base station 110 to a UE 120) or uplink communications (from a UE 120 to a base station 110).

[0185] As described above, providing Figure 4 is provided as an example. Other examples can differ from what is described. Figure 4 for the examples described with respect to

[0186] Sidelink communications can occur in a transmission and / or reception resource pool. A minimum resource allocation unit in frequency can be a subchannel. A resource allocation in time can be a slot. A slot can or can not be available for sidelink. A slot can or can not include feedback resources. Radio resource control (RRC) configuration of slots for a UE can be based at least in part on pre-configuration (e.g., pre-loaded on the UE) or configuration (e.g., from a base station).

[0187] Figure 5 is a diagram illustrating an example 500 of a slot structure, in accordance with the present disclosure.

[0188] As shown by reference number 502, a slot can be configured without feedback resources. The slot can include 14 OFDM symbols. The sidelink can be (pre)configured to occupy less than 14 symbols in the slot. The first symbol in the slot can be a repetition of the previous symbol for automatic gain control (AGC) purposes. The slot can include a PSCCH and a PSSCH. There can be a gap symbol after the PSSCH. A subchannel size can be (pre)configured to be {10, 15, 20, 25, 50, 75, 100} physical resource blocks (PRBs). The PSCCH and the PSSCH can be transmitted in the same slot.

[0189] As shown by reference number 504, a slot can be configured with feedback resources. The slot can include 14 OFDM symbols. The slot can include a PSCCH, a PSSCH, and a PSFCH. The resources for the PSFCH can be configured with a period of {0, 1, 2, 4} slots. The PSFCH can include two OFDM symbols, which can include a first OFDM symbol dedicated to the PSFCH and a second OFDM symbol for AGC purposes. There can be a gap symbol after the PSFCH.

[0190] As described above, providing Figure 5 as an example. Other examples can differ from what is described Figure 5 in the described examples.

[0191] For forward compatibility, SCI can be split into two stages. The SCI can include SCI-1 and SCI-2. The SCI-1 can be transmitted on the PSCCH and can include information for resource allocation and for decoding the SCI-2. The SCI-2 can be transmitted on the PSSCH and can include information for decoding data via the shared channel. Both the SCI-1 and the SCI-2 can use PDCCH polar codes to improve reliability.

[0192] The SCI-1 can include priority information (e.g., a QoS value), a PSSCH resource assignment (e.g., frequency / time resources for the PSSCH), a resource reservation period (if enabled), a PSSCH DMRS pattern (if more than one pattern is (pre)configured), a SCI-2 format (e.g., information associated with a size of the SCI-2), a two-bit beta offset for SCI-2 resource allocation, a number of PSSCH DMRS ports (e.g., one or two), and / or a 5-bit MCS.

[0193] The SCI-2 format can include a HARQ process ID, an NDI, a source ID, a destination ID, and / or a CSI report trigger (for unicast), which can be used to determine a new transport block or a transport block retransmission. For the groupcast option associated with distance-based feedback with NACK only, the SCI-2 format can include a zone ID indicating the location of the transmitter and / or the maximum communication range for sending feedback.

[0194] The PSCCH duration can be (pre-)configured to two or three symbols. The PSCCH can be (pre-)configured to span {10, 12, 15, 20, 25} PRBs and can be limited to a single subchannel. DMRS can be present in each PSCCH symbol and can be placed on every fourth resource element (RE). A frequency domain orthogonal cover code (FD-OCC) can be applied to the DMRS to reduce the impact of colliding PSCCH transmissions. The transmitter UE can randomly select from a set of predefined FD-OCCs. The starting symbol for PSCCH can be the second symbol in a slot (e.g., after the first symbol which can be used for AGC).

[0195] Figure 6 FIG. 6 is a diagram illustrating an example 600 of DMRS resource elements, in accordance with the present disclosure.

[0196] As shown in Figure 6 , multiple PSCCH REs can be in the frequency domain. DMRS can be present in the PSCCH symbols (e.g., in each PSCCH symbol). DMRS can occur in every fourth RE. That is, after three PSCCH REs in the frequency domain can be a single DMRS RE, and so on.

[0197] As described above, providing Figure 6 is an example. Other examples can differ from what is described. Figure 6 for the examples described with respect to

[0198] One and two layer transmissions can be supported using quadrature phase shift keying (QPSK), 16-quadrature amplitude modulation (16-QAM), 64-QAM, and / or 256-QAM. Two-symbol, three-symbol, and / or four-symbol DMRS patterns can be (pre-)configured for use by the transmitter. Depending on the channel conditions, the transmitter can select a DMRS pattern and can send an indication of the DMRS pattern in SCI-1. Further, DMRS patterns for 9-symbol PSSCH and / or 12-symbol PSSCH can be defined.

[0199] Figure 7 FIG. 7 is a diagram illustrating an example 700 of DMRS patterns, in accordance with the present disclosure.

[0200] As shown by reference number 702, a two-symbol DMRS pattern can include a first DMRS in symbol 3 and a second DMRS in symbol 10.

[0201] As shown by reference number 704, a three-symbol DMRS pattern can include a first DMRS in symbol 1, a second DMRS in symbol 6, and a third DMRS in symbol 11.

[0202] As shown by reference number 706, a four-symbol DMRS pattern can include a first DMRS in symbol 1, a second DMRS in symbol 4, a third DMRS in symbol 7, and a fourth DMRS in symbol 10.

[0203] As shown by reference number 708, a two-symbol DMRS pattern can include a first DMRS in symbol 4 and a second DMRS in symbol 8.

[0204] As shown by reference number 710, a three-symbol DMRS pattern can include a first DMRS in symbol 1, a second DMRS in symbol 4, and a third DMRS in symbol 7.

[0205] As described above, provide Figure 7 as an example. Other examples can differ from that described. Figure 7 described with respect to the examples described.

[0206] Figure 8 is a diagram illustrating an example 800 of sidelink control information, in accordance with the present disclosure.

[0207] As Figure 8 shown, SCI-2 can be mapped to contiguous resource blocks in the PSSCH starting from the first symbol with PSSCH DMRS. SCI-2 can be scrambled separately from the sidelink shared channel (SL-SCH) and can use QPSK. SCI-2 can not be associated with blind decoding because the SCI-2 format can be indicated in SCI-1, the number of REs can be derived from the SCI-1 content, and the starting position can be known. When the SL-SCH transmission is on two layers, the SCI-2 modulation symbols can be duplicated on both layers.

[0208] As described above, provide Figure 8 as an example. Other examples can differ from that described. Figure 8 described with respect to the examples described.

[0209] The feedback resources can be system-wide. The feedback resources can be (pre)configured with a periodicity N = {1, 2, 4} slots. When the feedback resources are configured, they can occupy three OFDM symbols, which include one gap symbol and two PSFCH symbols. The number of PRBs used for the actual PSFCH can be (pre)configured based at least in part on a bitmap.

[0210] PUCCH format 0 over one resource block can carry HARQ-ACK information for a single PSSCH transmission. The PSFCH format 0 sequence can be repeated over two PSFCH symbols. The PSFCH can be enabled for unicast and groupcast. The PSFCH for unicast can include a one-bit ACK / NACK. The PSFCH for groupcast can be associated with two feedback modes, where a first feedback mode can be associated with receiver UEs that only send NACK, and a second feedback mode can be associated with receiver UEs that send ACK or NACK.

[0211] Figure 9 FIG. 9 is a diagram illustrating an example 900 of PSFCH in a slot, in accordance with the present disclosure.

[0212] As shown in Figure 9 , a first slot (slot n) and a third slot (slot n+2) can include three symbols associated with SCI-1, two symbols associated with SCI-2, two symbols associated with PSFCH, a plurality of data symbols, and a pair of gap symbols around the PSFCH. A second slot (slot n+1) and a fourth slot (slot n+3) can include three symbols associated with SCI-1, two symbols associated with SCI-2, and a plurality of data symbols.

[0213] As described above, providing Figure 9 is an example. Other examples can differ from what is described. Figure 9 in this description.

[0214] Figure 10 FIG. 10 is a diagram illustrating an example 1000 of PSFCH resource mapping, in accordance with the present disclosure.

[0215] As shown in Figure 10 , a PSSCH can be mapped to a corresponding PSFCH resource based at least in part on the PSFCH resource mapping. The mapping between a PSSCH and a corresponding PSFCH resource can be based at least in part on a starting subchannel of the PSSCH, a slot containing the PSSCH, a source ID, and / or a destination ID. The number of available PSFCH resources can be equal to or greater than the number of UEs in the second groupcast option.

[0216] As described above, providing Figure 10As an example. Other examples can differ from what is described Figure 10 The described examples differ from the examples described

[0217] Figure 11 is a diagram illustrating an example 1100 of sidelink operation modes, in accordance with the present disclosure.

[0218] As shown by reference number 1102, a first resource allocation mode in NR sidelink can involve a base station allocating resources for sidelink communications between UEs. For example, the base station can transmit a resource grant to a first UE via a Uu interface. The first UE can communicate with a second UE via a sidelink interface (e.g., a PC5 interface) based at least in part on the resource grant received from the base station.

[0219] As shown by reference number 1104, a second resource allocation mode in NR sidelink can involve a UE autonomously selecting sidelink resources. For example, the first UE can select sidelink resources, and the first UE can communicate with the second UE based at least in part on the sidelink resources.

[0220] From a receiver’s perspective (e.g., a second UE receiving sidelink communications from a first UE), there can be no difference between the first resource allocation mode and the second resource allocation mode. Moreover, NR sidelink can support HARQ-based retransmissions.

[0221] As described above, providing Figure 11 As an example. Other examples can differ from what is described Figure 11 The described examples differ from the examples described

[0222] Figure 12 is a diagram illustrating an example 1200 of uplink tunneling via a relay, in accordance with the present disclosure.

[0223] One uplink coverage enhancement can involve dedicated uplink tunneling via a UE relay. A base station can use broadcast and / or groupcast to set up a multi-hop tunnel via a UE relay. The base station can set up the multi-hop tunnel in dedicated time and frequency resources. Based at least in part on the base station implementation, the number of hops can be limited to one or more remote UEs and / or one or more relay UEs.

[0224] As Figure 12As shown, the source UE, the first relay UE, and / or the second relay UE can receive groupcast signaling from the base station to setup uplink relay tunnels. Based at least in part on the groupcast signaling, the source UE can transmit uplink data to the first relay UE. The first relay UE can forward the uplink data to the second relay UE. The second relay UE can forward the uplink data to the base station. As a result, the source UE can communicate uplink data to the base station based at least in part on dedicated uplink tunnel transmissions via the first and second relay UEs.

[0225] Multiple relay configurations can be used for UEs. As an example, a UE can have a direct link to a base station and a next UE, but not to other UEs. As another example, a UE can have a direct link to other UEs regardless of the number of hops between the UE and the other UEs. As yet another example, UEs can be grouped into groups, where each group can communicate with a next group, and a single hop can be between groups.

[0226] As described above, there is provided Figure 12 as an example. Other examples can differ from that described. Figure 12 described examples.

[0227] Figure 13 FIG. 1300 is a schematic diagram illustrating an example of uplink tunnel transmission via relays, in accordance with the present disclosure.

[0228] As Figure 13 shown, the source UE can transmit uplink data to the first relay UE and the second relay UE via groupcast signaling on the PSSCH. The first relay UE can transmit uplink data to the third, fourth, and fifth relay UEs via groupcast signaling on the PSSCH. The second relay UE can transmit uplink data to the third, fourth, and fifth relay UEs via groupcast signaling on the PSSCH. The third relay UE can transmit uplink data to the base station via groupcast signaling on the PUSCH. The fourth relay UE can transmit uplink data to the base station via groupcast signaling on the PUSCH. The fifth relay UE can transmit uplink data to the base station via groupcast signaling on the PUSCH. As a result, the source UE can transmit uplink data to the base station based at least in part on dedicated uplink tunnel transmissions via the multiple relay UEs.

[0229] As described above, there is provided Figure 13 as an example. Other examples can differ from that described. Figure 13 described examples.

[0230] Figure 14 FIG. 1400 is a schematic diagram illustrating an example of sidelink communication, in accordance with the present disclosure.

[0231] The base station and the one or more UEs can communicate in the downlink via the PDCCH and the PDSCH. The base station and the one or more UEs can communicate in the uplink via the PUCCH and the PUSCH. The UEs can communicate with each other in the sidelink via the PSSCH and the PSCCH for sidelink communications. The UEs can communicate with each other in the sidelink via the PSFCH for sidelink feedback.

[0232] As Figure 14 indicated in the above, the base station can transmit a grant to the first UE. The base station can transmit the grant via the PDCCH or via RRC signaling. The first UE can transmit a sidelink transmission to the second UE based at least in part on the grant received from the base station. The first UE can transmit the sidelink transmission via the PSCCH and / or the PSSCH. The second UE can transmit sidelink feedback to the first UE based at least in part on the sidelink transmission. The second UE can transmit the sidelink feedback via the PSFCH. The first UE can transmit feedback to the base station via the PUCCH.

[0233] As described above, a Figure 14 example. Other examples can differ from that described. Figure 14 The described examples can be implemented in different examples.

[0234] Figure 15 is a diagram illustrating an example 1500 of a mapping between HARQ-ACK information bit values and cyclic shifts, in accordance with the present disclosure.

[0235] The PSFCH can carry one-bit HARQ-ACK feedback. For example, the HARQ-ACK feedback can indicate an ACK / NACK value of 0 or an ACK / NACK value of 1. The HARQ-ACK feedback can be associated with a cyclic shift amount, which can depend on the information bit. In a mapping of HARQ-ACK information bit values to cyclic shifts of a sequence from a pair of cyclic shifts for a PSFCH transmission, when the HARQ-ACK information includes an ACK or a NACK, the HARQ-ACK value 0 (NACK) can be mapped to a sequence cyclic shift of 0, and the HARQ-ACK value 1 (ACK) can be mapped to a sequence cyclic shift of 6. In a mapping of HARQ-ACK information bit values to cyclic shifts of a sequence from a pair of cyclic shifts for a PSFCH transmission, when the HARQ-ACK information includes only a NACK, the HARQ-ACK value 0 (NACK) can be mapped to a sequence cyclic shift of 0.

[0236] As Figure 15As shown, ACK / NACK value 0 can be mapped to cyclic shift value 0, and ACK / NACK value 1 can be mapped to cyclic shift value 1. Further, the range of cyclic shift values can be from 0 to 11 (a total of 12 cyclic shift values), and the distance between the cyclic shift value associated with ACK / NACK value 0 (cyclic shift value 0) and the cyclic shift value associated with ACK / NACK value 1 (cyclic shift value 6) can be equal to 6.

[0237] As described above, providing Figure 15 as an example. Other examples can differ from what is described Figure 15 in the described examples.

[0238] A receiving UE can determine CSI based at least in part on the PSSCH, and the CSI can be used for retransmission or transmission of new data. However, the receiving UE can communicate the CSI in a MAC-CE, which can be a relatively slow mechanism for the transmitting UE to receive the CSI and perform retransmission or transmission of new data based at least in part on the CSI.

[0239] In various implementations and techniques described herein, a receiving UE can transmit CSI based at least in part on the PSSCH signal, and the receiving UE can transmit the CSI on the PSFCH. Transmitting the CSI via the PSFCH can enable the transmitting UE to receive the CSI in a relatively short period of time as compared to transmitting the CSI in a MAC-CE. Further, in some aspects, the CSI can be transmitted by a UE that functions as a relay UE, which can improve coverage and reliability. For example, CSI feedback from a relay UE can include CQI / MCS and redundancy version index, which can represent the starting bits in the coded bit circular buffer.

[0240] In various implementations and techniques described herein, a relay UE can be used to improve coverage and reliability of the PC5 interface between sidelink UEs. CSI feedback from a relay UE can increase the set of decoding relays across different hops, but can allow additional relay UEs to decode the data. In addition to parity bits, some RVs can have more systematic bits (e.g., original bits), while other RVs can have partial systematic bits or no systematic bits. RVs with more systematic bits, such as RV0 or RV3, can be self-decodable. In the case of strong interference or poor channel quality, using certain RV indices can benefit the receiving UE. As a result, the receiving UE can recommend that the transmitting UE perform the next transmission with a certain RV index, which can improve decoding and reliability.

[0241] Figure 16 FIG. 16 is a diagram illustrating an example 1600 associated with CSI feedback for sidelink communications, in accordance with the present disclosure.

[0242] In some aspects, HARQ-ACK feedback and CSI feedback can be associated with the same PSFCH resource. For example, the PSFCH can carry a total of two bits of HARQ-ACK feedback and CSI feedback. The HARQ-ACK feedback can include acknowledgement / negative-acknowledgement (A / N) feedback. Further, a mapping of cyclic shift values with equal distances to feedback values can be defined, and the A / N feedback can be associated with the most significant bits (MSBs) and the CSI feedback can be associated with the least significant bits (LSBs).

[0243] As shown in Figure 16 , cyclic shift value 0 can represent A / N feedback value 0 and CSI feedback value 0, cyclic shift value 3 can represent A / N feedback value 0 and CSI feedback value 1, cyclic shift value 6 can represent A / N feedback value 1 and CSI feedback value 1, and / or cyclic shift value 9 can represent A / N feedback value 1 and CSI feedback value 0. In this example, equal distances between cyclic shift values can be used when mapping the cyclic shift values to feedback values associated with A / N and CSI.

[0244] As described above, providing Figure 16 as an example. Other examples can differ from what is described Figure 16 in the examples described in this disclosure.

[0245] Figure 17 is a diagram illustrating an example 1700 associated with CSI feedback for sidelink communications, in accordance with the present disclosure.

[0246] In some aspects, HARQ-ACK feedback and CSI feedback can be associated with the same PSFCH resource. For example, the PSFCH can carry a total of two bits of HARQ-ACK feedback and CSI feedback. The HARQ-ACK feedback can include A / N feedback. The bits indicated in the PSFCH can be associated with different priority levels. For example, the A / N feedback can be associated with a high priority bit and the CSI feedback can be associated with a low priority bit. Further, a mapping of cyclic shift values with unequal distances to feedback values can be defined, and the A / N feedback can be associated with the MSBs and the CSI feedback can be associated with the LSBs.

[0247] As shown in Figure 17 , cyclic shift value 0 can represent A / N feedback value 0 and CSI feedback value 0, cyclic shift value 2 can represent A / N feedback value 0 and CSI feedback value 1, cyclic shift value 6 can represent A / N feedback value 1 and CSI feedback value 1, and / or cyclic shift value 8 can represent A / N feedback value 1 and CSI feedback value 0. In this example, unequal distances between cyclic shift values can be used when mapping the cyclic shift values to feedback values associated with A / N and CSI.

[0248] As an example, the following is provided: Figure 17 Other examples can differ from what is described Figure 17 in connection with the described examples.

[0249] Figure 18 FIG. 18 is a diagram illustrating an example 1800 associated with CSI feedback for sidelink communications, in accordance with the present disclosure.

[0250] In some aspects, HARQ-ACK feedback and CSI feedback can be associated with the same PSFCH resource. For example, the PSFCH can carry a total of two bits of HARQ-ACK feedback and CSI feedback. The HARQ-ACK feedback can include A / N feedback. The bits indicated in the PSFCH can be associated with different priority levels. For example, the A / N feedback can be associated with high priority bits, and the CSI feedback can be associated with low priority bits. Further, a mapping of cyclic shift values to feedback values can be defined with unequal distances, and the A / N feedback can be associated with LSBs, and the CSI feedback can be associated with MSBs.

[0251] As an example, the following is provided: Figure 18 Cyclic shift value 0 can represent CSI feedback value 0 and A / N feedback value 0, cyclic shift value 4 can represent CSI feedback value 0 and A / N feedback value 1, cyclic shift value 6 can represent CSI feedback value 1 and A / N feedback value 1, and / or cyclic shift value 10 can represent CSI feedback value 1 and A / N feedback value 0. In this example, unequal distances between cyclic shift values can be used when mapping the cyclic shift values to feedback values associated with A / N and CSI.

[0252] As an example, the following is provided: Figure 18 Other examples can differ from what is described Figure 18 in connection with the described examples.

[0253] Figure 19 FIG. 19 is a diagram illustrating an example 1900 associated with CSI feedback for sidelink communications, in accordance with the present disclosure.

[0254] In some aspects, HARQ-ACK feedback and CSI feedback can be associated with the same PSFCH resource. For example, the PSFCH can carry a total of three or four bits of HARQ-ACK feedback and CSI feedback. The HARQ-ACK feedback can include A / N feedback. The A / N feedback can be associated with MSBs, and the CSI feedback (e.g., two or three bits of CSI feedback) can be associated with the remaining bits. That is, a first bit can be associated with A / N feedback, and the remaining two or three bits can be associated with CSI feedback.

[0255] As Figure 19 illustrated, a first cyclic shift value can represent A / N feedback value 0, first CSI feedback value 0, and second CSI feedback value 0. A second cyclic shift value can represent A / N feedback value 0, first CSI feedback value 0, and second CSI feedback value 1. A third cyclic shift value can represent A / N feedback value 0, first CSI feedback value 1, and second CSI feedback value 0. A fourth cyclic shift value can represent A / N feedback value 0, first CSI feedback value 1, and second CSI feedback value 1. A fifth cyclic shift value can represent A / N feedback value 1, first CSI feedback value 1, and second CSI feedback value 1. A sixth cyclic shift value can represent A / N feedback value 1, first CSI feedback value 1, and second CSI feedback value 0. A seventh cyclic shift value can represent A / N feedback value 1, first CSI feedback value 0, and second CSI feedback value 0. An eighth cyclic shift value can represent A / N feedback value 1, first CSI feedback value 0, and second CSI feedback value 1.

[0256] As described above, providing Figure 19 as an example. Other examples can differ from Figure 19 the examples described.

[0257] In some aspects, more than one resource block can be used to transmit CSI including CQI, MCS, rank indicator (RI), and / or RV index. The CSI can be transmitted using multiple resource blocks or PSFCH resources, where each PSFCH resource can have a single resource block. In some aspects, the same A / N bits can be transmitted across multiple resource blocks or PSFCH resources, and different CSI can be transmitted across multiple resource blocks or PSFCH resources. As a result, the amount of CSI that can be transmitted increases while allowing for increased reliability of the A / N transmission.

[0258] As an example, for four resource blocks, encoding can be performed separately on each resource block. A first resource block can be associated with A / N feedback and first CSI feedback, a second resource block can be associated with A / N feedback and second CSI feedback, a third resource block can be associated with A / N feedback and third CSI feedback, and a fourth resource block can be associated with A / N feedback and fourth CSI feedback. That is, each resource block can include the same A / N bits and one CSI bit from a 4-bit CSI sequence. In this example, the CSI feedback can be four bits because the first, second, third, and fourth CSI can each be one bit.

[0259] In some aspects, two or more resources of the PSFCH can be constructed such that one PSFCH resource can be associated with HARQ-ACK feedback and one or more PSFCH resources can be associated with CSI feedback. One PSFCH resource for HARQ-ACK feedback can be transmitted in one resource block. The PSFCH resources can be selected based at least in part on the mapped resources from PSSCH reception. In some aspects, each resource for CSI feedback can have one or more bits.

[0260] As an example, for four resource blocks, encoding can be performed separately on each resource block. A first resource block can be associated with A / N feedback, a second resource block can be associated with CSI feedback, a third resource block can be associated with CSI feedback, and a fourth resource block can be associated with CSI feedback. The CSI feedback associated with the second, third, and fourth resource blocks can correspond to a sequence of 4-bit CSI. That is, CSI from the 4-bit CSI sequence can be transmitted on the three remaining resource blocks. Each resource block of the PSFCH can have four bits of separate encoding. Alternatively, joint encoding can be used across the three remaining resource blocks for CSI feedback, where four bits can be encoded using a long sequence. As a result, a long sequence can be generated having a size of three resource blocks to encode the 4-bit CSI.

[0261] In some aspects, a NACK-only feedback period can be configured. For example, a configuration can be transmitted to a UE to enable the UE to provide NACK-only decoding feedback. CSI feedback can be configured to be transmitted with the NACK-only event. For NACK-only feedback, and when CSI feedback is needed in the NACK-only case, a NACK bit can not be transmitted. Instead, the bit can be used instead to transmit CSI feedback. That is, for NACK-only feedback, one bit for NACK can not be transmitted, and the one bit can be used instead to transmit CSI feedback. Further, when CSI feedback includes more than one bit of information, additional resources can be used to transmit the CSI feedback. A power level associated with the CSI feedback can indicate that a NACK transmission is present. That is, a power level associated with the CSI feedback can not satisfy a threshold, which can implicitly indicate a NACK transmission.

[0262] In some aspects, an ACK-only feedback period can be configured. CSI feedback can be configured to be transmitted with the ACK-only event. For ACK-only feedback, an ACK bit can not be transmitted. Instead, the bit can be used instead to transmit CSI feedback.

[0263] In some aspects, the CSI feedback can be based at least in part on the PSSCH, and the CSI feedback can indicate a DMRS RSRP, a CQI / MCS based at least in part on the received data signal, an RV index for retransmission (e.g., a best RV index relative to other RV indexes), and / or a data rank (e.g., a best data rank relative to other data ranks). Since the CSI feedback can include one or more bits, a quantization level of the parameters can be signaled using RRC signaling and / or a MAC-CE.

[0264] As an example, when only an MCS / CQI is signaled as the CSI feedback and one bit is used for the CSI feedback, a first bit value (e.g., 0) can indicate a first value to fallback from the current CQI / MCS, and a second bit value (e.g., 1) can indicate a second value to fallback from the current MCS / CQI, where the first value and the second value can be pre-signaled in RRC or MAC-CE.

[0265] Figure 20 FIG. 16 is a diagram illustrating an example 1600 of CSI feedback associated with sidelink communications, in accordance with the present disclosure.

[0266] As Figure 20 indicated in FIG. 16, a base station can transmit a grant to a first UE. The base station can transmit the grant via a PDCCH or via RRC signaling. The first UE can transmit a sidelink transmission to a second UE based at least in part on the grant received from the base station. The first UE can transmit the sidelink transmission via a PSCCH and / or a PSSCH. The second UE can transmit a sidelink feedback to the first UE based at least in part on the sidelink transmission. The second UE can transmit the sidelink feedback via a PSFCH. The sidelink feedback can include an A / N feedback and a CSI feedback based at least in part on the sidelink transmission. The first UE can transmit feedback to the base station via a PUCCH. The feedback can include the A / N feedback and the CSI feedback. In addition, the base station can transmit the feedback to the first UE via a PDCCH. The feedback can include the A / N feedback and the CSI feedback.

[0267] As described above, providing Figure 20 as an example. Other examples can differ from what is described Figure 20 above, as specified herein.

[0268] Figure 21 FIG. 17 is a diagram illustrating an example 1700 of CSI feedback associated with sidelink communications, in accordance with the present disclosure.

[0269] As Figure 21As shown, a source UE can transmit a first sidelink transmission to a relay UE. The source UE can be one hop away from the relay UE. The source UE can transmit the first sidelink transmission via a PSCCH and / or a PSSCH. The relay UE can transmit sidelink feedback to the source UE based at least in part on the first sidelink transmission. The relay UE can transmit the sidelink feedback via a PSFCH. The sidelink feedback can include A / N feedback and CSI feedback based at least in part on the sidelink transmission. The CSI feedback can include various CSI parameters, such as a DMRS RSRP, a CQI / MCS based at least in part on a received data signal, an RV index, and / or a data rank. That is, the CSI feedback can indicate new / updated CSI and / or transmission parameters. The source UE can transmit a second sidelink transmission to the relay UE via a PSCCH and / or a PSSCH. The relay UE can transmit the second sidelink transmission based at least in part on the CSI parameters as previously indicated from the source UE to the relay UE.

[0270] In some aspects, when the A / N feedback includes an ACK, the ACK can not be associated with CSI feedback. When the A / N feedback includes a NACK, the CSI feedback can be transmitted. In some aspects, the ACK can be associated with CSI feedback for upcoming packet relaying.

[0271] As described above, there is provided Figure 21 as an example. Other examples can differ from Figure 21 the examples described.

[0272] In some aspects, a base station can transmit feedback regarding an RV index via a PDCCH on a Uu link. The RV index can be a best next RV index, which can be used by a next relay UE or a set of relay UEs. In some aspects, when only one relay UE is transmitting at a time, this RV index can be used in the next transmission. In some aspects, when multiple relay UEs are transmitting to the base station at the same time and using the same resources, the multiple UEs can all use the same RV index. The relay UEs can use the suggested RV index from the base station to perform transmissions. In some aspects, when each relay UE is transmitting individually, the base station can inform each relay UE of the best RV index to use.

[0273] Figure 22 FIG. 22 is a diagram illustrating an example 2200 associated with CSI feedback for sidelink communications, in accordance with the present disclosure.

[0274] As Figure 22As shown, the source UE can transmit uplink data to the first relay UE and the second relay UE via groupcast signaling on the PSSCH. The first relay UE can transmit uplink data to the third relay UE and the fourth relay UE via groupcast signaling on the PSSCH. The second relay UE can transmit uplink data to the third relay UE and the fourth relay UE via groupcast signaling on the PSSCH. The third relay UE can transmit uplink data to the base station via groupcast signaling on the PUSCH. The fourth relay UE can transmit uplink data to the base station via groupcast signaling on the PUSCH.

[0275] In some aspects, a relay UE can overhear transmitted information across multiple hops. For example, a relay UE can be a next-hop transmitting relay UE, and the relay UE can transmit an indication to a current-hop relay UE of a best RV index for the current-hop relay UE to use. The next-hop transmitting relay UE can transmit the indication based at least in part on the next-hop transmitting relay UE receiving the at least one sidelink communication.

[0276] As further shown in Figure 22 As an example, even though the source UE, the first relay UE, and / or the second relay UE can be multiple hops away from the third relay UE, the third relay UE can overhear the source UE, the first relay UE, and the second relay UE. In this case, the third relay UE can transmit an indication of a best RV index for the third relay UE for a next sidelink transmission based at least in part on a transmitting node (e.g., the source UE, the first relay UE, or the second relay UE). In some aspects, the first relay UE and / or the second relay UE can decode a PSFCH associated with the third relay UE to obtain the best RV index for the third relay UE. The first relay UE and / or the second relay UE can transmit a sidelink transmission to the third relay UE based at least in part on the best RV index for the third relay UE. In some aspects, the first relay UE and / or the second relay UE can perform a groupcast transmission to the third relay UE and the fourth relay UE based at least in part on the best RV index for the third relay UE.

[0277] As described above, providing Figure 22 As an example. Other examples can differ from that described. Figure 22 The described examples can be implemented in different ways.

[0278] In some aspects, a transmitting UE can transmit data in a multicast manner. Since different relay UEs can transmit different indications of a best RV index, a transmitting UE one hop away can determine a best CSI (e.g., RV index, MCS, etc.) based at least in part on an aggregation of CSI feedback from different relay UEs. The transmitting UE can transmit the aggregated CSI feedback information associated with a transmission in SCI via a PSSCH.

[0279] In some aspects, the transmitting UE can transmit the data in a unicast manner. In this case, the transmitting UE can transmit a transport block to the receiving UE with the recommended CSI (e.g., RV index, MCS, etc.) of the receiving UE.

[0280] Figure 23 FIG. 23 is a diagram illustrating an example process 2300 performed, for example, by a first UE, in accordance with aspects of the present disclosure. Example process 2300 is an example of a process in which a first UE (e.g., UE 120a) performs operations associated with techniques for channel state information feedback for sidelink communications.

[0281] As Figure 23 As shown in FIG. 23, in some aspects, process 2300 can include receiving, from a second UE, a sidelink communication via a PSSCH (block 2310). For example, the UE (e.g., using reception component 2502, shown in FIG. 25) can receive, from a second UE, a sidelink communication via a PSSCH, as described above. Figure 25 As shown in FIG. 23, in some aspects, process 2300 can include receiving, from a second UE, a sidelink communication via a PSSCH (block 2310). For example, the UE (e.g., using reception component 2502, shown in FIG. 25) can receive, from a second UE, a sidelink communication via a PSSCH, as described above.

[0282] As Figure 23 As further shown in FIG. 23, in some aspects, process 2300 can include transmitting, to the second UE, HARQ-ACK feedback and CSI feedback on a single PSFCH resource based at least in part on the sidelink communication via the PSSCH (block 2320). For example, the UE (e.g., using transmission component 2504, shown in FIG. 25) can transmit, to the second UE, HARQ-ACK feedback and CSI feedback on a single PSFCH resource based at least in part on the sidelink communication via the PSSCH, as described above. Figure 25 As further shown in FIG. 23, in some aspects, process 2300 can include transmitting, to the second UE, HARQ-ACK feedback and CSI feedback on a single PSFCH resource based at least in part on the sidelink communication via the PSSCH (block 2320). For example, the UE (e.g., using transmission component 2504, shown in FIG. 25) can transmit, to the second UE, HARQ-ACK feedback and CSI feedback on a single PSFCH resource based at least in part on the sidelink communication via the PSSCH, as described above.

[0283] Process 2300 can include additional aspects, such as any single aspect or any combination of aspects described below and / or in connection with one or more other processes described herein.

[0284] In a first aspect, process 2300 includes selecting a cyclic shift value for transmitting the HARQ-ACK feedback and the CSI feedback based at least in part on a bit value associated with the HARQ-ACK feedback and a bit value associated with the CSI feedback.

[0285] In a second aspect, alone or in combination with the first aspect, the selection of the cyclic shift value is from a set of cyclic shift values associated with an equal distance between other cyclic shift values in the set of cyclic shift values.

[0286] In a third aspect, alone or in combination with one or more of the first and second aspects, the selection of the cyclic shift value is from a set of cyclic shift values associated with unequal distances between other cyclic shift values in the set of cyclic shift values.

[0287] In a fourth aspect, alone or in combination with one or more of the first through third aspects, HARQ-ACK feedback is associated with a first bit and CSI feedback is associated with a second bit.

[0288] In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, the first bit is associated with a first priority level and the second bit is associated with a second priority level.

[0289] In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, the first bit is associated with a most significant bit and the second bit is associated with a least significant bit.

[0290] In a seventh aspect, alone or in combination with one or more of the first through sixth aspects, the first bit is associated with a least significant bit and the second bit is associated with a most significant bit.

[0291] In an eighth aspect, alone or in combination with one or more of the first through seventh aspects, HARQ-ACK feedback is associated with a first bit and CSI feedback is associated with two or more bits.

[0292] In a ninth aspect, alone or in combination with one or more of the first through eighth aspects, the transmission of CSI feedback uses two or more PSFCH resources, wherein a same HARQ-ACK feedback is associated with each of the two or more PSFCH resources, and wherein different CSI feedback is associated with each of the two or more PSFCH resources.

[0293] In a tenth aspect, alone or in combination with one or more of the first through ninth aspects, the transmission of HARQ-ACK feedback and CSI feedback uses two or more PSFCH resources, wherein a first subset of the two or more PSFCH resources is associated with HARQ-ACK feedback and a second subset of the two or more PSFCH resources is associated with CSI feedback.

[0294] In an eleventh aspect, alone or in combination with one or more of the first through tenth aspects, the process 2300 includes transmitting additional CSI feedback in place of HARQ-ACK feedback based at least in part on a NACK-only feedback configuration associated with the first UE, wherein a NACK bit is repurposed to convey the additional CSI feedback.

[0295] In a twelfth aspect, alone or in combination with one or more of the first through eleventh aspects, the CSI indicates one or more of a demodulation reference signal received power, a channel quality indicator or a modulation and coding scheme based at least in part on the sidelink communication received from the second UE, a redundancy version index for a retransmission of the sidelink communication, or a data rank.

[0296] In a thirteenth aspect, alone or in combination with one or more of the first through twelfth aspects, the process 2300 includes receiving, from the base station via radio resource control signaling or via a MAC-CE, an indication of a quantization level of a parameter associated with CSI feedback.

[0297] In a fourteenth aspect, alone or in combination with one or more of the first through thirteenth aspects, the first UE is a source UE and the second UE is a relay UE.

[0298] In a fifteenth aspect, alone or in combination with one or more of the first through fourteenth aspects, the first UE is a relay UE and the second UE is a source UE.

[0299] In a sixteenth aspect, alone or in combination with one or more of the first through fifteenth aspects, the sidelink communication is a first sidelink communication, and further comprising: receiving, from the second UE, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

[0300] In a seventeenth aspect, alone or in combination with one or more of the first through sixteenth aspects, the process 2300 includes receiving, from the base station via a physical downlink control channel, an indication of a redundancy version index that the first UE applies when performing a subsequent transmission to the base station, wherein the redundancy version index is applicable to the first UE or to a group of UEs including the first UE and the second UE; and performing the subsequent transmission to the base station based at least in part on the redundancy version index.

[0301] In an eighteenth aspect, alone or in combination with one or more of the first through seventeenth aspects, the process 2300 includes transmitting, to the second UE, an indication of a redundancy version that the second UE applies when the second UE is performing a sidelink communication with the first UE; and wherein receiving the sidelink communication comprises receiving the sidelink communication based at least in part on the redundancy version.

[0302] In a nineteenth aspect, alone or in combination with one or more of the first through eighteenth aspects, the process 2300 includes transmitting, to the second UE, an indication of a redundancy version applied by the second UE when the second UE is performing the sidelink communication with the first UE; and wherein receiving the sidelink communication includes receiving the sidelink communication via a groupcast communication based at least in part on the redundancy version.

[0303] In a twentieth aspect, alone or in combination with one or more of the first through nineteenth aspects, the process 2300 includes determining aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and performing a multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

[0304] Although Figure 23 Example blocks of the process 2300 are illustrated, but in some aspects, the process 2300 can include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those shown in FIG. 23. Additionally, or alternatively, two or more of the blocks of the process 2300 can be performed in parallel. Figure 23

[0305] Figure 24 FIG. 24 is a schematic diagram illustrating an example process 2400 that, for example, is performed by a first UE, in accordance with the present disclosure. Example process 2400 is an example where the first UE (e.g., UE 120a) performs operations associated with techniques for channel state information feedback for sidelink communications.

[0306] As Figure 24 shown, in some aspects, the process 2400 can include transmitting, to a second UE, a sidelink communication via a PSSCH (block 2410). For example, the UE (e.g., using transmission component 2504, shown in FIG. 25) can transmit, to a second UE, a sidelink communication via a PSSCH, as described above. Figure 25

[0307] As further shown in Figure 24 FIG. 25, in some aspects, the process 2400 can include receiving, from the second UE and based at least in part on the sidelink communication, HARQ-ACK feedback and CSI feedback on a single PSFCH resource (block 2420). For example, the UE (e.g., using reception component 2502, shown in FIG. 25) can receive, from the second UE and based at least in part on the sidelink communication, HARQ-ACK feedback and CSI feedback on a single PSFCH resource, as described above. Figure 25

[0308] ​​​Process 2400 can include additional aspects, such as any single aspect or any combination of aspects described below and / or in connection with one or more other processes described herein.

[0309] In a first aspect, process 2400 includes that the first UE is a source UE and the second UE is a relay UE; or the first UE is a relay UE and the second UE is a source UE.

[0310] In a second aspect, alone or in combination with the first aspect, the sidelink communication is a first sidelink communication, and further comprising transmitting, to the second UE, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

[0311] In a third aspect, alone or in combination with one or more of the first and second aspects, process 2400 includes receiving, from the base station via a physical downlink control channel, an indication of a redundancy version index for the first UE to apply when performing a subsequent transmission to the base station, wherein the redundancy version index is applicable to the first UE or to a group of UEs including the first UE and the second UE; and performing the subsequent transmission to the base station based at least in part on the redundancy version index.

[0312] In a fourth aspect, alone or in combination with one or more of the first through third aspects, process 2400 includes receiving, from the second UE, an indication of a redundancy version for the first UE to apply when performing a sidelink communication with the second UE; and wherein transmitting the sidelink communication includes transmitting the sidelink communication based at least in part on the redundancy version.

[0313] In a fifth aspect, alone or in combination with one or more of the first through fourth aspects, process 2400 includes receiving, from the second UE, an indication of a redundancy version for the first UE to apply when performing a sidelink communication with the second UE; and wherein transmitting the sidelink communication includes transmitting the sidelink communication via a groupcast communication based at least in part on the redundancy version.

[0314] In a sixth aspect, alone or in combination with one or more of the first through fifth aspects, process 2400 includes determining aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and performing a multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

[0315] Although Figure 24 An example block of process 2400 is shown, but in some aspects, process 2400 can include additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in Figure 24Additional blocks, fewer blocks, different blocks, or differently arranged blocks can be used. Additionally or alternatively, two or more of the blocks of process 2400 can be performed in parallel.

[0316] Figure 25 FIG. 25 is a block diagram of an example apparatus 2500 for wireless communication. The apparatus 2500 can be a first UE, or a first UE can include the apparatus 2500. In some aspects, the apparatus 2500 includes a reception component 2502 and a transmission component 2504, which can be in communication with one another (for example, via one or more buses and / or one or more other components). As shown, the apparatus 2500 can communicate with another apparatus 2506 (such as a UE, a base station, or another wireless communication device) using the reception component 2502 and the transmission component 2504. As further shown, the apparatus 2500 can include one or more of a selection component 2508 or a determination component 2510 and / or the like.

[0317] In some aspects, the apparatus 2500 can be configured to perform one or more operations described herein with reference to Figures 16-22 one or more processes described herein. Additionally, or alternatively, the apparatus 2500 can be configured to perform one or more processes described herein, such as process 2300 of Figure 23 FIG. 23, Figure 24 process 2400 of FIG. 24, or a combination thereof. In some aspects, Figure 25 the apparatus 2500 and / or one or more components thereof illustrated in Figure 2 may include one or more components of the first UE described above in connection with Figure 25 Additionally, or alternatively, one or more components illustrated in Figure 2 may be implemented within one or more components of the apparatus 2500 described above in connection with Additionally, or alternatively, one or more components of the set of components can be implemented at least in part as software stored in a memory. For example, a component (or a portion of a component) can be implemented as instructions or code stored in a non-transitory computer-readable medium and executable by a controller or a processor to perform the functions or operations of the component.

[0318] Figure 2 The reception component 2502 can receive communications, such as reference signals, control information, data communications, or a combination thereof, from the apparatus 2506. The reception component 2502 can provide received communications to one or more other components of the apparatus 2500. In some aspects, the reception component 2502 can perform signal processing on the received communications (such as filtering, amplification, demodulation, analog-to-digital conversion, demultiplexing, deinterleaving, de-mapping, equalization, interference cancellation, or decoding, among other examples), and can provide the processed signals to the one or more other components of the apparatus 2506. In some aspects, the reception component 2502 can include one or more components of the reception component 2102 described above in connection with FIG. 21.The one or more antennas, demodulators, MIMO detector, receive processor, controller / processor, memory, or combination thereof of the described first UE.

[0319] The transmission component 2504 can transmit communications, such as reference signals, control information, data communications, or a combination thereof, to the apparatus 2506. In some aspects, one or more other components of the apparatus 2506 can generate communications and can provide the generated communications to the transmission component 2504 for transmission to the apparatus 2506. In some aspects, the transmission component 2504 can perform signal processing on the generated communications (such as filtering, amplification, modulation, digital-to-analog conversion, multiplexing, interleaving, mapping, or encoding, among other examples), and can transmit the processed signals to the apparatus 2506. In some aspects, the transmission component 2504 can include one or more antennas, a modulator, a transmit MIMO processor, a transmit processor, a controller / processor, a memory, or combination thereof, as described above. Figure 2 The one or more antennas, demodulators, MIMO detector, receive processor, controller / processor, memory, or combination thereof of the described first UE.

[0320] The reception component 2502 can receive, from a second UE, a sidelink communication via a PSSCH. The transmission component 2504 can transmit, to the second UE, HARQ-ACK feedback and CSI feedback on a single PSFCH resource based at least in part on the sidelink communication via the PSSCH.

[0321] The selection component 2508 can select a cyclic shift value for transmitting the HARQ-ACK feedback and the CSI feedback based at least in part on a bit value associated with the HARQ-ACK feedback and a bit value associated with the CSI feedback.

[0322] The transmission component 2504 can transmit, based at least in part on a NACK-only decoding feedback configuration associated with the first UE, additional CSI feedback in place of the HARQ-ACK feedback, where a NACK bit is repurposed to convey the additional CSI feedback. The reception component 2502 can receive, from a base station, an indication of a quantization level of a parameter associated with the CSI feedback via radio resource control signaling or via a MAC-CE. The reception component 2502 can receive, from the base station, an indication of a redundancy version index that the first UE applies when performing a subsequent transmission to the base station via a physical downlink control channel, where the redundancy version index is applicable to the first UE or to a group of UEs including the first UE and a second UE.

[0323] The transmitting component 2504 can perform subsequent transmissions to the base station based at least in part on the redundancy version index. The transmitting component 2504 can send an indication to the second UE of the redundancy version applied by the second UE when the second UE is performing sidelink communication with the first UE.

[0324] The determining component 2510 can determine aggregated feedback information for multiple UEs, wherein the aggregated feedback information indicates CSI for the multiple UEs. The transmitting component 2504 can perform multicast transmission to the multiple UEs based at least in part on the aggregated feedback information.

[0325] Transmitting component 2504 can transmit sidelink communication to the second UE via PSSCH. Receiving component 2502 can receive HARQ-ACK feedback and CSI feedback on a single PSSCH resource from the second UE and at least in part based on the sidelink communication.

[0326] The receiving component 2502 can receive from the base station via a physical downlink control channel an indication of a redundant version index applied by the first UE when performing subsequent transmissions to the base station, wherein the redundant version index is applicable to the first UE or to a group of UEs including the first UE and the second UE.

[0327] The transmitting component 2504 can perform subsequent transmissions to the base station based at least in part on the redundancy version index. The receiving component 2502 can receive from the second UE an indication of the redundancy version applied by the first UE when performing sidelink communication with the second UE.

[0328] The determining component 2510 can determine aggregated feedback information for multiple UEs, wherein the aggregated feedback information indicates CSI for the multiple UEs. The transmitting component 2504 can perform multicast transmission to the multiple UEs based at least in part on the aggregated feedback information.

[0329] Provided as an example Figure 25 The number and arrangement of components are shown. In practice, with... Figure 25 Compared to the components shown, there may be additional components, fewer components, different components, or components arranged differently. Furthermore, Figure 25 The two or more components shown can be implemented within a single component, or Figure 25 The single component shown can be implemented as multiple distributed components. Alternatively,Figure 25 The set of components shown in FIG. 1 can perform one or more functions described as being performed by the set of components shown in Figure 25 The set of components shown in FIG. 1 can perform one or more functions described as being performed by the set of components shown in

[0330] An overview of some aspects of the present disclosure is provided below:

[0331] Aspect 1 : A method of wireless communication performed by a first user equipment (UE), comprising: receiving, from a second UE, a sidelink communication via a physical sidelink shared channel (PSSCH); and transmitting, to the second UE, hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback and channel state information (CSI) feedback on a single physical sidelink feedback channel (PSFCH) resource based at least in part on the sidelink communication via the PSSCH.

[0332] Aspect 2: The method of aspect 1, further comprising: selecting a cyclic shift value for transmitting the HARQ-ACK feedback and the CSI feedback based at least in part on a bit value associated with the HARQ-ACK feedback and a bit value associated with the CSI feedback.

[0333] Aspect 3: The method of aspect 2, wherein the selection of the cyclic shift value is from a set of cyclic shift values associated with an equal distance between other cyclic shift values in the set of cyclic shift values.

[0334] Aspect 4: The method of aspect 2, wherein the selection of the cyclic shift value is from a set of cyclic shift values associated with a non-equal distance between other cyclic shift values in the set of cyclic shift values.

[0335] Aspect 5: The method of any one of aspects 1-4, wherein the HARQ-ACK feedback is associated with a first bit and the CSI feedback is associated with a second bit.

[0336] Aspect 6: The method of aspect 5, wherein the first bit is associated with a first priority level and the second bit is associated with a second priority level.

[0337] Aspect 7: The method of aspect 5, wherein the first bit is associated with a most significant bit and the second bit is associated with a least significant bit.

[0338] Aspect 8: The method of aspect 5, wherein the first bit is associated with a least significant bit and the second bit is associated with a most significant bit.

[0339] Aspect 9: The method of any of aspects 1 through 8, wherein the HARQ-ACK feedback is associated with a first bit and the CSI feedback is associated with two or more bits.

[0340] Aspect 10: The method of any of aspects 1 through 9, wherein the transmission of the CSI feedback uses two or more PSFCH resources, wherein a same HARQ-ACK feedback is associated with each of the two or more PSFCH resources, and wherein different CSI feedback is associated with each of the two or more PSFCH resources.

[0341] Aspect 11: The method of any of aspects 1 through 10, wherein the transmission of the HARQ-ACK feedback and the CSI feedback uses two or more PSFCH resources, wherein a first subset of the two or more PSFCH resources is associated with the HARQ-ACK feedback and a second subset of the two or more PSFCH resources is associated with the CSI feedback.

[0342] Aspect 12: The method of any of aspects 1 through 11, further comprising transmitting additional CSI feedback in place of the HARQ-ACK feedback based at least in part on a negative-acknowledgement (NACK) only decoding feedback configuration associated with the first UE, wherein a NACK bit is repurposed to convey the additional CSI feedback.

[0343] Aspect 13: The method of any of aspects 1 through 12, wherein the CSI indicates one or more of a demodulation reference signal received power, a channel quality indicator or a modulation and coding scheme based at least in part on a sidelink communication received from a second UE, a redundancy version index for a retransmission of a sidelink communication, or a data rank.

[0344] Aspect 14: The method of any of aspects 1 through 13, further comprising receiving, from a base station, an indication of a quantization level of a parameter associated with the CSI feedback via radio resource control signaling or via a medium access control control element.

[0345] Aspect 15: The method of any of aspects 1 through 14, wherein the first UE is a source UE and the second UE is a relay UE.

[0346] Aspect 16: The method of any of aspects 1 through 15, wherein the first UE is a relay UE and the second UE is a source UE.

[0347] Aspect 17: The method of any of aspects 1 through 16, wherein the sidelink communication is a first sidelink communication, and further comprising: receiving, from the second UE, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

[0348] Aspect 18: The method of any of aspects 1 through 17, further comprising: receiving, from a base station via a physical downlink control channel, an indication of a redundancy version index for the first UE to apply when performing a subsequent transmission to the base station, wherein the redundancy version index is applicable to the first UE or to a group of UEs including the first UE and the second UE; and performing the subsequent transmission to the base station based at least in part on the redundancy version index.

[0349] Aspect 19: The method of any of aspects 1 through 18, further comprising: transmitting, to the second UE, an indication of a redundancy version for the second UE to apply when the second UE is performing the sidelink communication with the first UE; and wherein receiving the sidelink communication comprises receiving the sidelink communication based at least in part on the redundancy version.

[0350] Aspect 20: The method of any of aspects 1 through 19, further comprising: transmitting, to the second UE, an indication of a redundancy version for the second UE to apply when the second UE is performing the sidelink communication with the first UE; and wherein receiving the sidelink communication comprises receiving the sidelink communication via a groupcast communication based at least in part on the redundancy version.

[0351] Aspect 21 : The method of any of aspects 1 through 20, further comprising: determining aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and performing a multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

[0352] Aspect 22: A method of wireless communication performed by a first user equipment (UE), comprising: transmitting, to a second UE, a sidelink communication via a physical sidelink shared channel (PSSCH); and receiving, from the second UE and based at least in part on the sidelink communication, hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback and channel state information (CSI) feedback on a single physical sidelink feedback channel (PSFCH) resource.

[0353] Aspect 23: The method of aspect 22, wherein: the first UE is a source UE and the second UE is a relay UE; or the first UE is a relay UE and the second UE is a source UE.

[0354] Aspect 24: The method of any one of aspects 22-23, wherein the sidelink communication is a first sidelink communication, and further comprising: transmitting, to the second UE, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

[0355] Aspect 25: The method of any one of aspects 22-24, further comprising: receiving, from a base station via a physical downlink control channel, an indication of a redundancy version index for the first UE to apply when performing a subsequent transmission to the base station, wherein the redundancy version index is applicable to the first UE or to a group of UEs including the first UE and the second UE; and performing the subsequent transmission to the base station based at least in part on the redundancy version index.

[0356] Aspect 26: The method of any one of aspects 22-25, further comprising: receiving, from the second UE, an indication of a redundancy version for the first UE to apply when performing the sidelink communication with the second UE; and wherein transmitting the sidelink communication comprises transmitting the sidelink communication based at least in part on the redundancy version.

[0357] Aspect 27: The method of any one of aspects 22-26, further comprising: receiving, from the second UE, an indication of a redundancy version for the first UE to apply when performing the sidelink communication with the second UE; and wherein transmitting the sidelink communication comprises transmitting the sidelink communication via a groupcast communication based at least in part on the redundancy version.

[0358] Aspect 28: The method of any one of aspects 22-27, further comprising: determining aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and performing a multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

[0359] Aspect 29: An apparatus for wireless communication at a device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to implement a method of one or more aspects of aspects 1-21.

[0360] Aspect 30: A device for wireless communication, comprising a memory and one or more processors coupled to the memory, the memory and the one or more processors configured to perform the method of one or more aspects of aspects 1-21.

[0361] Aspect 31 : An apparatus for wireless communication, comprising at least one means for performing the method of one or more aspects of aspects 1-21.

[0362] Aspect 32 : A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to implement a method of one or more aspects of aspects 1-21.

[0363] Aspect 33 : A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more aspects of aspects 1-21.

[0364] Aspect 34 : An apparatus for wireless communication at a device, comprising a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method of one or more aspects of aspects 22-28.

[0365] Aspect 35 : A device for wireless communication, comprising a memory and one or more processors coupled to the memory, the memory and the one or more processors configured to perform the method of one or more aspects of aspects 22-28.

[0366] Aspect 36 : An apparatus for wireless communication, comprising at least one means for performing the method of one or more aspects of aspects 22-28.

[0367] Aspect 37 : A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to implement a method of one or more aspects of aspects 22-28.

[0368] Aspect 38 : A non-transitory computer-readable medium storing a set of instructions for wireless communication, the set of instructions comprising one or more instructions that, when executed by one or more processors of a device, cause the device to perform the method of one or more aspects of aspects 22-28.

[0369] The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise forms disclosed. Modifications and variations can be made in light of the above disclosure or can be acquired from practice of the aspects.

[0370] As used herein, the term “component” is intended to be broadly interpreted to include hardware, firmware, and / or combinations of hardware and software. As used herein, a processor is implemented in hardware, firmware, and / or combinations of hardware and software. It will be apparent that systems and / or methods described herein can be implemented in different forms of hardware, firmware, and / or a combination of hardware and software. The actual specialized control hardware or software code used to implement these systems and / or methods is not limiting of the aspects. Thus, the operation and behavior of the systems and / or methods were described herein without reference to specific software code — it being understood that software and hardware can be designed to implement the systems and / or methods based, at least in part, on the description herein.

[0371] As used herein, depending on the context, satisfying a threshold can refer to a value being greater than the threshold, a value being greater than or equal to the threshold, a value being less than the threshold, a value being less than or equal to the threshold, a value being equal to the threshold, a value not being equal to the threshold, and / or the like.

[0372] Although specific combinations of features are recited in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of various aspects. In fact, many of these features can be combined in ways not specifically recited in the claims and / or disclosed in the specification. Although each dependent claim listed below can directly depend on only one claim, the disclosure of each aspect includes each dependent claim in combination with every other claim in the set of claims. As used herein, a phrase referring to “at least one of’ a list of items refers to any combination of those items, including single members. As an example, “at least one of a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination of multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c).

[0373] 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 can be used interchangeably with “one or more.” Furthermore, as used herein, the article “the” is intended to include one or more items referenced, and can be used interchangeably with “the one or more.” Also, as used herein, the terms “set” and “group” are intended to include one or more items (e.g., related items, unrelated items, or a combination of related and unrelated items), and can be used interchangeably with “one or more.” Where only one item is intended, the phrase “only one” or similar language is used. Also, as used herein, the terms “has,” “have,” “having,” 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 can be used interchangeably with “and / or,” unless explicitly stated otherwise (e.g., if used in combination with “either” or “only one of’).

Claims

1. A method of wireless communication performed by a first user equipment (UE), comprising: receiving, from a second UE, a sidelink communication via a physical sidelink shared channel (PSSCH); and transmitting, to the second UE, hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback and channel state information (CSI) feedback on a single physical sidelink feedback channel (PSFCH) resource based at least in part on the sidelink communication via the PSSCH, wherein a cyclic shift value used to transmit the HARQ-ACK feedback and the CSI feedback is selected based at least in part on a bit value associated with the HARQ-ACK feedback and a bit value associated with the CSI feedback.

2. The method of claim 1, wherein, the selection of the cyclic shift value is from a set of cyclic shift values associated with equal distances between other cyclic shift values in the set of cyclic shift values.

3. The method of claim 1, wherein, the selection of the cyclic shift value is from a set of cyclic shift values associated with unequal distances between other cyclic shift values in the set of cyclic shift values.

4. The method of claim 1, wherein, the HARQ-ACK feedback is associated with a first bit and the CSI feedback is associated with a second bit.

5. The method of claim 4, wherein, the first bit is associated with a first priority level and the second bit is associated with a second priority level.

6. The method of claim 4, wherein, the first bit is associated with a most significant bit and the second bit is associated with a least significant bit.

7. The method of claim 4, wherein, the first bit is associated with a least significant bit and the second bit is associated with a most significant bit.

8. The method of claim 1, wherein, the HARQ-ACK feedback is associated with a first bit and the CSI feedback is associated with two or more bits.

9. The method of claim 1, wherein, the transmission of the CSI feedback uses two or more PSFCH resources, wherein a same HARQ-ACK feedback is associated with each of the two or more PSFCH resources, and wherein different CSI feedback is associated with each of the two or more PSFCH resources.

10. The method of claim 1, wherein, the transmission of the HARQ-ACK feedback and the CSI feedback uses two or more PSFCH resources, wherein a first subset of the two or more PSFCH resources is associated with the HARQ-ACK feedback and a second subset of the two or more PSFCH resources is associated with the CSI feedback.

11. The method of claim 1, further comprising: transmitting, instead of the HARQ-ACK feedback, additional CSI feedback based at least in part on a negative acknowledgement (NACK) only decoding feedback configuration associated with the first UE, wherein a NACK bit is repurposed to convey the additional CSI feedback.

12. The method of claim 1, wherein, The CSI indicates one or more of a demodulation reference signal received power, a channel quality indicator based at least in part on the sidelink communication received from the second UE, or a modulation and coding scheme, a redundancy version index for a retransmission of the sidelink communication, or data rank.

13. The method of claim 1, further comprising: receiving, via radio resource control signaling or via a medium access control control element, an indication of a quantization level of a parameter associated with the CSI feedback.

14. The method of claim 1, wherein, The first UE is a source UE and the second UE is a relay UE.

15. The method of claim 1, wherein, The first UE is a relay UE and the second UE is a source UE.

16. The method of claim 1, wherein, The sidelink communication is a first sidelink communication, and wherein the method further comprises: receiving, from the second UE, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

17. The method of claim 1, further comprising: receiving, via a physical downlink control channel, an indication of a redundancy version index that the first UE applies when performing a subsequent transmission, wherein the redundancy version index is applicable to the first UE or to a group of UEs that includes the first UE and the second UE; and performing the subsequent transmission based at least in part on the redundancy version index.

18. The method of claim 1, further comprising: transmitting, to the second UE, an indication of a redundancy version that the second UE applies when the second UE is performing the sidelink communication with the first UE; and wherein receiving the sidelink communication comprises receiving the sidelink communication based at least in part on the redundancy version.

19. The method of claim 1, further comprising: transmitting, to the second UE, an indication of a redundancy version that the second UE applies when the second UE is performing the sidelink communication with the first UE; and wherein receiving the sidelink communication comprises receiving the sidelink communication via a groupcast communication based at least in part on the redundancy version.

20. The method of claim 1, further comprising: determining aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and performing a multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

21. A method of wireless communication performed by a first user equipment (UE), comprising: transmitting, to a second UE, a sidelink communication via a physical sidelink shared channel (PSSCH); and receiving, from the second UE and based at least in part on the sidelink communication, hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback and channel state information (CSI) feedback on a single physical sidelink feedback channel (PSFCH) resource, wherein a cyclic shift value for transmitting the HARQ-ACK feedback and the CSI feedback is selected based at least in part on a bit value associated with the HARQ-ACK feedback and a bit value associated with the CSI feedback.

22. The method of claim 21, wherein: the first UE is a source UE and the second UE is a relay UE; or the first UE is a relay UE and the second UE is a source UE.

23. The method of claim 21, wherein, the sidelink communication is a first sidelink communication, and wherein the method further comprises: transmitting, to the second UE, a second sidelink communication based at least in part on the HARQ-ACK feedback and the CSI feedback.

24. The method of claim 21, further comprising: receiving, via a physical downlink control channel, an indication of a redundancy version index for the first UE to apply when performing a subsequent transmission, wherein the redundancy version index is applicable to the first UE or to a group of UEs including the first UE and the second UE; and performing the subsequent transmission based at least in part on the redundancy version index.

25. The method of claim 21, further comprising: receiving, from the second UE, an indication of a redundancy version for the first UE to apply when performing the sidelink communication with the second UE; and wherein transmitting the sidelink communication comprises transmitting the sidelink communication based at least in part on the redundancy version.

26. The method of claim 21, further comprising: receiving, from the second UE, an indication of a redundancy version for the first UE to apply when performing the sidelink communication with the second UE; and wherein transmitting the sidelink communication comprises transmitting the sidelink communication via a groupcast communication based at least in part on the redundancy version.

27. The method of claim 21, further comprising: determining aggregated feedback information for a plurality of UEs, wherein the aggregated feedback information indicates CSI for the plurality of UEs; and performing a multicast transmission to the plurality of UEs based at least in part on the aggregated feedback information.

28. A first user equipment (UE) for wireless communication, comprising: a memory; and one or more processors coupled to the memory, the one or more processors configured to: receive, from a second UE, a sidelink communication via a physical sidelink shared channel (PSSCH); and transmit, to the second UE, hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback and channel state information (CSI) feedback on a single physical sidelink feedback channel (PSFCH) resource based at least in part on the sidelink communication via the PSSCH, wherein a cyclic shift value for transmitting the HARQ-ACK feedback and the CSI feedback is selected based at least in part on a bit value associated with the HARQ-ACK feedback and a bit value associated with the CSI feedback. ​ ​ ​ 29. The first UE of claim 28, wherein, the HARQ-ACK feedback is associated with a first bit and the CSI feedback is associated with a second bit, and wherein the first bit is associated with a first priority level and the second bit is associated with a second priority level.

30. A first user equipment (UE) for wireless communication, comprising: a memory; and one or more processors coupled to the memory, the one or more processors configured to: transmit, to a second UE, a sidelink communication via a physical sidelink shared channel (PSSCH); and receive, from the second UE and based at least in part on the sidelink communication, hybrid automatic repeat request acknowledgement (HARQ-ACK) feedback and channel state information (CSI) feedback on a single physical sidelink feedback channel (PSFCH) resource, wherein a cyclic shift value for the HARQ-ACK feedback and the CSI feedback is selected based at least in part on a bit value associated with the HARQ-ACK feedback and a bit value associated with the CSI feedback.

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