# US 12,120,655 B2 · Time-division multiplexing sounding reference signal ports > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,120,655 B2 - Document ID: US12120655B2 - Status: Granted - Kind: B2 - Application number: 17/456,836 - Filed: 2021-11-29 - Published: 2023-06-01 - Granted: 2024-10-15 - Earliest claimed: 2021-11-29 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Muhammad Sayed Khairy Abdelghaffar; Jing Jiang; Joseph Patrick Burke; Tingfang Ji; Peter Gaal; Alexei Yurievitch Gorokhov - Web page: https://patentgrep.com/patent/US12120655B2 ## CPC - H04L 5/0051: {of dedicated pilots, i.e. pilots destined for a single user or terminal} - H04W 72/046: {the resource being in the space domain, e.g. beams} - H04B 7/0684: {using different training sequences per antenna} - H04J 13/004: {Orthogonal} - H04L 5/0026: {Division using four or more dimensions, e.g. beam steering or quasi-co-location [QCL]} - H04L 5/0048: {Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091)} - H04L 5/0092: {Indication of how the channel is divided} - H04L 27/2613: {Structure of the reference signals} - H04L 27/26132: {using repetition} - H04W 72/0446: Resources in time domain, e.g. slots or frames - H04L 5/0023: {Time-frequency-space} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04B: TRANSMISSION - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) ## Abstract A user equipment (UE) may spatial time-division multiplex a plurality of sounding reference signal (SRS) ports, each of the plurality of SRS ports being associated with at least one of a set of orthogonal weights, the set of orthogonal weights corresponding to phase shifting, and transmit a plurality of SRSs via the plurality of spatially time-division multiplexed SRS ports simultaneously, each of the plurality of SRSs including at least two SRS repetition. The plurality of SRSs may be configured to form or present a quasi-co-location (QCL) receive (Rx) beam subspace. The UE may configure the plurality of SRSs to form the subspace as the QCL Rx beam subspace, and a base station may signal the UE to a specific Rx beam subspace such that it is aligned to the base station's beamforming direction, and achieve spatial multiplexing gain in the QCL Rx beam subspace. ## Claims ### Claim 1 An apparatus for wireless communication at a user equipment (UE), comprising: memory; and at least one processor coupled to the memory and configured to, at least in part with the memory: spatial time-division multiplex a plurality of sounding reference signal (SRS) ports based on a transient period between two consecutive symbols of the plurality of spatially time-division multiplexed SRS ports, each of the plurality of SRS ports being associated with at least one of a set of orthogonal weights, the set of orthogonal weights corresponding to phase shifting, wherein the transient period starts from a transient start time and is provided for the phase shifting between the two consecutive symbols; and transmit, to a base station, a plurality of SRSs via the plurality of spatially time-division multiplexed SRS ports simultaneously, each of the plurality of SRSs including at least two SRS repetitions. ### Claim 2 (depends on 1) The apparatus of claim 1, further comprising a transceiver coupled to the at least one processor, wherein a number of the plurality of SRS ports is equal to a number of SRS repetitions in each of the plurality of SRSs. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the plurality of SRSs is intra-slot allocated within one slot or inter-slot allocated across consecutive slots. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein, to spatially time-division multiplex the plurality of SRS ports, the at least one processor is configured to: configure the transient period between the two consecutive symbols of the plurality of spatially time-division multiplexed SRS ports. ### Claim 5 (depends on 4) The apparatus of claim 4, wherein to configure the transient period between the two consecutive symbols, the at least one processor is configured to configure the transient period symmetrically between the two consecutive symbols. ### Claim 6 (depends on 4) The apparatus of claim 4, wherein the transient start time and the transient period are based on a capability of the UE. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein the at least one processor is further configured to: amplify a transmission power of the at least two SRS repetitions from a single transmit (Tx) chain; and divide the amplified transmission power of the at least two SRS repetitions into the plurality of SRSs transmitted via the plurality of spatially time-division multiplexed SRS ports. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein the at least one processor is further configured to: divide a transmission power of the at least two SRS repetitions from a single transmit (Tx) chain into the plurality of SRSs; and amplify a transmission power for all of the plurality of SRSs prior to simultaneously transmitting, to the base station, the plurality of SRSs via the plurality of spatially time-division multiplexed SRS ports. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein the set of orthogonal weights includes a set of time-domain orthogonal cover codes (TD-OCCs). ### Claim 10 (depends on 9) The apparatus of claim 9, wherein the at least one processor is further configured to receive, from the base station, a configuration of the set of TD-OCCs. ### Claim 11 (depends on 10) The apparatus of claim 10, wherein to receive the configuration of the set of TD-OCCs, the at least one processor is configured to receive the configuration of the set of TD-OCCs via at least one of a radio resource control (RRC) message, a medium access control (MAC) control element (CE) (MAC-CE), or downlink control information (DCI). ### Claim 12 (depends on 1) The apparatus of claim 1, wherein the set of orthogonal weights includes orthogonal vectors of a discrete Fourier transform (DFT) based codebook. ### Claim 13 (depends on 1) The apparatus of claim 1, wherein the at least one processor is further configured to: transmit, to the base station, a UE capability for simultaneously transmitting the plurality of SRSs; and receive, from the base station, a configuration of the time-division multiplexing each of the plurality of SRS ports, wherein the configuration of time-division multiplexing is based on the UE capability for simultaneously transmitting the plurality of SRSs. ### Claim 14 (depends on 1) The apparatus of claim 1, wherein the plurality of SRS ports is associated with a beam subspace, and transmission of the plurality of SRSs via the plurality of SRS ports forms a quasi-co-location (QCL) receive (Rx) beam subspace, and wherein the at least one processor is further configured to: receive, from the base station, a downlink transmission via at least one transmit (Tx) beam of the base station, wherein the at least one Tx beam of the base station is aligned with the QCL Rx beam subspace. ### Claim 15 (depends on 1) The apparatus of claim 1, wherein at least a portion of the plurality of SRSs including the at least two SRS repetitions is allocated within a symbol. ### Claim 16 (depends on 1) The apparatus of claim 1, wherein at least a portion of the plurality of SRSs overlaps with at least one other uplink signal or channel, and the plurality of SRSs are associated with a higher transmission priority compared to the at least one other uplink signal or channel. ### Claim 17 (depends on 16) The apparatus of claim 16, wherein the at least one processor is further configured to drop at least one or more ports of the plurality of SRS ports based on a location or a number of symbols of the portion of the plurality of SRSs overlapping with the at least one other uplink signal or channel. ### Claim 18 An apparatus for wireless communication at a base station, comprising: memory; and at least one processor coupled to the memory and configured to, at least in part with the memory: transmit, to a user equipment (UE), a configuration of spatial time-division multiplexing for the UE to spatially time-division multiplex a plurality of sounding reference signal (SRS) ports, each of the plurality of SRS ports being associated with at least one of a set of orthogonal weights, the set of orthogonal weights corresponding to phase shifting, and wherein a transient period is set between two consecutive symbols of the plurality of spatially time-division multiplexed SRS ports, wherein the transient period starts from a transient start time and is provided for the phase shifting between the two consecutive symbols; and receive, from the UE, a plurality of SRSs via the plurality of spatially time-division multiplexed SRS ports simultaneously, each of the plurality of SRSs including at least two SRS repetitions. ### Claim 19 (depends on 18) The apparatus of claim 18, further comprising a transceiver coupled to the at least one processor, wherein a number of the plurality of SRS ports is equal to a number of SRS repetitions in each of the plurality of SRSs. ### Claim 20 (depends on 18) The apparatus of claim 18, wherein the plurality of SRSs including the at least two SRS repetitions is intra-slot allocated within one slot or inter-slot allocated across consecutive slots. ### Claim 21 (depends on 18) The apparatus of claim 18, wherein the transient period is set between the two consecutive symbols of the plurality of spatially time-division multiplexed SRS ports. ### Claim 22 (depends on 21) The apparatus of claim 21, wherein the transient period is configured symmetrically between the two consecutive symbols. ### Claim 23 (depends on 21) The apparatus of claim 21, wherein the transient start time and the transient period are based on a capability of the UE. ### Claim 24 (depends on 18) The apparatus of claim 18, wherein the set of orthogonal weights includes a set of time-domain orthogonal cover codes (TD-OCCs). ### Claim 25 (depends on 18) The apparatus of claim 18, wherein the set of orthogonal weights includes orthogonal vectors of a discrete Fourier transform (DFT) based codebook. ### Claim 26 (depends on 18) The apparatus of claim 18, wherein the at least one processor is further configured to: receive, from the UE, a UE capability for simultaneously transmitting the plurality of SRSs, wherein the configuration of time-division multiplexing is based on the UE capability for simultaneously transmitting the plurality of SRSs. ### Claim 27 (depends on 18) The apparatus of claim 18, wherein the plurality of SRS ports is associated with a beam subspace, and reception of the plurality of SRSs via the plurality of SRS ports forms a quasi-co-location (QCL) receive (Rx) beam subspace. ### Claim 28 (depends on 27) The apparatus of claim 27, wherein the at least one processor is further configured to: transmit, to the UE, a downlink transmission via at least one transmit (Tx) beam of the base station, wherein the at least one of the Tx beam is aligned with the QCL Rx beam subspace. ### Claim 29 A method of wireless communication at a user equipment (UE), comprising: spatial time-division multiplexing a plurality of sounding reference signal (SRS) ports based on a transient period between two consecutive symbols of the plurality of spatially time-division multiplexed SRS ports, each of the plurality of SRS ports being associated with at least one of a set of orthogonal weights, the set of orthogonal weights corresponding to phase shifting, wherein the transient period starts from a transient start time and is provided for the phase shifting between the two consecutive symbols; and transmitting, to a base station, a plurality of SRSs via the plurality of spatially time-division multiplexed SRS ports simultaneously, each of the plurality of SRSs including at least two SRS repetitions. ### Claim 30 A method of wireless communication at a base station (BS), comprising: transmitting, to a user equipment (UE), a configuration of spatial time-division multiplexing for the UE to spatially time-division multiplex a plurality of sounding reference signal (SRS) ports, each of the plurality of SRS ports being associated with at least one of a set of orthogonal weights, the set of orthogonal weights corresponding to phase shifting, and wherein a transient period is set between two consecutive symbols of the plurality of spatially time-division multiplexed SRS ports, wherein the transient period starts from a transient start time and is provided for the phase shifting between the two consecutive symbols; and receiving, from the UE, a plurality of SRSs via the plurality of spatially time-division multiplexed SRS ports simultaneously, each of the plurality of SRSs including at least two SRS repetitions.