# US 12,003,445 B2 · Multiple user (MU) support for reference signal (RS) and data multiplexing on shared uplink (UL) resources(s) > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,003,445 B2 - Document ID: US12003445B2 - Status: Granted - Kind: B2 - Application number: 17/448,625 - Filed: 2021-09-23 - Published: 2022-03-31 - Granted: 2024-06-04 - Earliest claimed: 2020-09-29 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Yi Huang; Peter Gaal; Wei Yang - Web page: https://patentgrep.com/patent/US12003445B2 ## CPC - 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 5/0051: {of dedicated pilots, i.e. pilots destined for a single user or terminal} - H04B 7/06: at the transmitting station - H04L 5/0007: {the frequencies being orthogonal, e.g. OFDM(A) or DMT} - H04L 5/0019: {in which one code is applied, as a temporal sequence, to all frequencies} - H04L 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals} - H04L 27/26134: {Pilot insertion in the transmitter chain, e.g. pilot overlapping with data, insertion in time or frequency domain} - H04L 27/2634: {Inverse fast Fourier transform [IFFT] or inverse discrete Fourier transform [IDFT] modulators in combination with other circuits for modulation} - H04L 27/2636: {with FFT or DFT modulators, e.g. standard single-carrier frequency-division multiple access [SC-FDMA] transmitter or DFT spread orthogonal frequency division multiplexing [DFT-SOFDM]} - H04W 72/1268: of uplink data flows - H04L 5/0023: {Time-frequency-space} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04B: TRANSMISSION - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Certain aspects of the present disclosure provide techniques for applying a mechanism to signals, from different user equipments (UEs), multiplexed for UL transmission, such that the mechanism differentiates one UE's waveform from another UE's, even if the waveforms are on the same time resources. A method that may be performed by a UE includes determining a mechanism to allow the UE to share uplink (UL) resources with at least one other UE for UL transmission, applying the mechanism to at least one of RS symbols or information symbols to be multiplexed using orthogonal frequency division multiplexing (OFDM) before performing a discrete Fourier transform (DFT) for the UL transmission, and outputting a waveform for the UL transmission after performing the DFT and an inverse fast Fourier transform (IFFT). ## Claims ### Claim 1 A method for wireless communications performed by a user equipment (UE), comprising: determining a mechanism to allow the UE to share uplink (UL) resources with at least one other UE for UL transmission, wherein determining the mechanism is based, at least in part, on an indication received from a network entity; applying the mechanism to at least one of reference signal (RS) symbols or information symbols to be multiplexed using orthogonal frequency division multiplexing (OFDM) before performing a discrete Fourier transform (DFT) for the UL transmission; and outputting a waveform for the UL transmission after performing the DFT and an inverse fast Fourier transform (IFFT). ### Claim 2 (depends on 1) The method of claim 1, wherein: the UL transmission comprises a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH); and the information symbols comprises at least one of data symbols or uplink control information (UCI) symbols. ### Claim 3 (depends on 1) The method of claim 1, wherein: the RS symbols comprise demodulation reference signal (DMRS) symbols; and the mechanism comprises an orthogonal cover code (OCC) applied to the DMRS symbols. ### Claim 4 (depends on 3) The method of claim 3, wherein the OCC is applied to achieve block level spreading of the DMRS symbols. ### Claim 5 (depends on 3) The method of claim 3, wherein the OCC is applied to achieve symbol level spreading of the DMRS symbols. ### Claim 6 (depends on 1) The method of claim 1, wherein the mechanism involves using different demodulation reference signal (DMRS) sequences for the UE and the at least one other UE to support multiple user (MU) transmission for DMRSs. ### Claim 7 (depends on 6) The method of claim 6, wherein: the UE and the at least one other UE both use a same sequence generator; and the UE and the at least one other UE both use different initialization seeds for the sequence generator to generate the different DMRS sequences. ### Claim 8 (depends on 1) The method of claim 1, wherein the mechanism comprises an orthogonal cover code (OCC) applied to the information symbols. ### Claim 9 (depends on 8) The method of claim 8, wherein the OCC is applied to achieve block level spreading of the information symbols. ### Claim 10 (depends on 8) The method of claim 8, wherein the OCC is applied to achieve symbol level spreading of the information symbols. ### Claim 11 A method for wireless communications performed by a network entity, comprising: transmitting, to different user equipments (UEs), an indication of a mechanism to apply to allow the different UEs to shared uplink (UL) resources for UL transmissions; receiving a waveform with UL transmissions from the different UEs on the shared UL resources; and applying the mechanism to distinguish at least one of reference signal (RS) symbols or information symbols multiplexed using orthogonal frequency division multiplexing (OFDM) from the different UEs after performing a fast Fourier transform (FFT) of the waveform, extracting tones for each of the different UEs, and performing an inverse discrete Fourier transform (IDFT). ### Claim 12 (depends on 11) The method of claim 11, wherein: the UL transmission comprises a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH); and the information symbols comprise at least one of data symbols or uplink control information (UCI) symbols. ### Claim 13 (depends on 11) The method of claim 11, wherein: the RS symbols comprise demodulation reference signal (DMRS) symbols; and the mechanism comprises an orthogonal cover code (OCC) applied to the DMRS symbols. ### Claim 14 (depends on 13) The method of claim 13, wherein the OCC is applied to achieve block level de-spreading of the DMRS symbols. ### Claim 15 (depends on 13) The method of claim 13, wherein the OCC is applied to achieve symbol level de-spreading of the DMRS symbols. ### Claim 16 (depends on 11) The method of claim 11, wherein the mechanism involves assigning different demodulation reference signal (DMRS) sequences for the different UEs to support multiple user (MU) transmission for DMRS. ### Claim 17 (depends on 16) The method of claim 16, wherein: the different UEs use a same sequence generator; and the different UEs are assigned different initialization seeds for the sequence generator to generate different DMRS sequences. ### Claim 18 (depends on 11) The method of claim 11, wherein the mechanism comprises an orthogonal cover code (OCC) applied to the information symbols. ### Claim 19 (depends on 18) The method of claim 18, wherein the OCC is applied to achieve block level de-spreading of the information symbols. ### Claim 20 (depends on 18) The method of claim 18, wherein the OCC is applied to achieve symbol level de-spreading of the information symbols. ### Claim 21 An apparatus for wireless communications performed by a user equipment (UE), comprising: at least one processor; and a memory coupled to the at least one processor, the memory including instructions executable by the at least one processor to cause the apparatus to: determine a mechanism to allow the UE to share uplink (UL) resources with at least one other UE for UL transmission, wherein determining the mechanism is based, at least in part, on an indication received from a network entity; apply the mechanism to at least one of reference signal (RS) symbols or information symbols to be multiplexed using orthogonal frequency division multiplexing (OFDM) before performing a discrete Fourier transform (DFT) for the UL transmission; and output a waveform for the UL transmission after performing the DFT and an inverse fast Fourier transform (IFFT). ### Claim 22 (depends on 21) The apparatus of claim 21, wherein: the UL transmission comprises a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH); and the information symbols comprises at least one of data symbols or uplink control information (UCI) symbols. ### Claim 23 (depends on 21) The apparatus of claim 21, wherein: the RS symbols comprise demodulation reference signal (DMRS) symbols; and the mechanism comprises an orthogonal cover code (OCC) applied to the DMRS symbols. ### Claim 24 (depends on 21) The apparatus of claim 21, wherein the mechanism comprises an orthogonal cover code (OCC) applied to the information symbols. ### Claim 25 An apparatus for wireless communications performed by a network entity, comprising: at least one processor; and a memory coupled to the at least one processor, the memory including instructions executable by the at least one processor to cause the apparatus to: transmit, to different user equipments (UEs), an indication of a mechanism to apply to allow the different UEs to shared uplink (UL) resources for UL transmissions; receive a waveform with UL transmissions from the different UEs on the shared UL resources; and apply the mechanism to distinguish at least one of reference signal (RS) symbols or information symbols multiplexed using orthogonal frequency division multiplexing (OFDM) from the different UEs after performing a fast Fourier transform (FFT) of the waveform, extracting tones for each of the different UEs, and performing an inverse discrete Fourier transform (IDFT). ### Claim 26 (depends on 25) The apparatus of claim 25, wherein: the UL transmission comprises a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH); and the information symbols comprise at least one of data symbols or uplink control information (UCI) symbols. ### Claim 27 (depends on 25) The apparatus of claim 25, wherein: the RS symbols comprise demodulation reference signal (DMRS) symbols; and the mechanism comprises an orthogonal cover code (OCC) applied to the DMRS symbols. ### Claim 28 (depends on 25) The apparatus of claim 25, wherein the mechanism comprises an orthogonal cover code (OCC) applied to the information symbols.