# US 12,120,050 B2 · Blind common phase error and residual carrier frequency offset mitigation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,120,050 B2 - Document ID: US12120050B2 - Status: Granted - Kind: B2 - Application number: 17/717,682 - Filed: 2022-04-11 - Published: 2023-10-12 - Granted: 2024-10-15 - Earliest claimed: 2022-04-11 - Applicants: QUALCOMM Incorporated - Inventors: Michael Levitsky; Assaf Touboul; Lev Zavurov; Daniel Paz; Gideon Shlomo Kutz - Web page: https://patentgrep.com/patent/US12120050B2 ## 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} - H04L 25/0238: {using blind estimation} - H04L 27/0014: {Carrier regulation (of chaotic carriers H04L27/001; for multicarrier receivers H04L27/2657)} - H04L 27/2601: {Multicarrier modulation systems} - H04W 72/1263: Mapping of traffic onto schedule, e.g. scheduled allocation or multiplexing of flows - H04L 2027/0026: {Correction of carrier offset} - 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) ## Abstract Methods, systems, and devices for wireless communications are described. The described techniques support blind common phase error (CPE) and residual carrier frequency offset mitigation. Generally, the described techniques provide for blind CPE mitigation at a receiving device without a phase tracking reference signal (PTRS) associated with less overhead and improved performance as compared to use of a PTRS to mitigate CPE. A receiving device may receive a shared channel message in a scheduled shared channel allocation in accordance with a PTRS configuration that omits a PTRS allocation based on a capability of the receiving device to apply blind CPE mitigation for shared channel receptions. In some examples, with a single DMRS symbol allocation, blind CPE mitigation for each subsequent data symbol of a shared channel message may be based on the blind CPE estimation for the previous symbol, which may enable robust mitigation of a residual carrier frequency offset. ## Claims ### Claim 1 A method for wireless communications at a user equipment (UE), comprising: receiving, from a network device, control signaling indicating parameters for a phase tracking reference signal configuration for a downlink shared channel reception, the parameters indicating to the UE that the phase tracking reference signal configuration omits a phase tracking reference signal based at least in part on a capability of the UE to apply blind common phase error mitigation for downlink shared channel receptions; and receiving, from the network device, control information scheduling a downlink shared channel allocation without a phase tracking reference signal. ### Claim 2 (depends on 1) The method of claim 1, wherein receiving the control signaling comprises: receiving the control signaling via a radio resource control message. ### Claim 3 (depends on 1) The method of claim 1, further comprising: receiving a downlink shared channel message in the downlink shared channel allocation in accordance with the parameters. ### Claim 4 (depends on 3) The method of claim 3, wherein receiving the downlink shared channel message comprises: receiving the downlink shared channel message conveyed by the downlink shared channel allocation based at least in part on applying the blind common phase error mitigation as a part of a downlink shared channel allocation demodulation process. ### Claim 5 (depends on 4) The method of claim 4, wherein applying the blind common phase error mitigation comprises: determining a blind common phase error estimation; and applying a blind common phase error correction based at least in part on the blind common phase error estimation. ### Claim 6 (depends on 5) The method of claim 5, further comprising: receiving, with the control information, scheduling information for a set of downlink shared channel allocations associated with a set of component carriers and without a phase tracking reference signal, wherein the downlink shared channel allocation is associated with a first component carrier; and receiving a set of downlink shared channel messages transmitted simultaneously with the downlink shared channel message via the set of downlink shared channel allocations associated with the set of component carriers based at least in part on the determined blind common phase error estimation for the downlink shared channel message. ### Claim 7 (depends on 3) The method of claim 3, wherein receiving the downlink shared channel message comprises: receiving a plurality of orthogonal frequency-division multiplexing symbols in the downlink shared channel allocation comprising a single demodulation reference signal and a set of orthogonal frequency-division multiplexing data symbols. ### Claim 8 (depends on 7) The method of claim 7, wherein receiving the downlink shared channel message further comprises: applying a first common phase error mitigation to a first orthogonal frequency-division multiplexing data symbol of the set of orthogonal frequency-division multiplexing data symbols, wherein the first orthogonal frequency-division multiplexing data symbol comprises a nearest orthogonal frequency-division multiplexing data symbol to the single demodulation reference signal; and demodulating the first orthogonal frequency-division multiplexing data symbol of the set of orthogonal frequency-division multiplexing data symbols based at least in part on the first common phase error mitigation. ### Claim 9 (depends on 8) The method of claim 8, wherein receiving the downlink shared channel message further comprises: applying a second common phase error mitigation to a second orthogonal frequency-division multiplexing data symbol of the set of orthogonal frequency-division multiplexing data symbols based at least in part on a common phase error estimation of the first orthogonal frequency-division multiplexing data symbol, the second orthogonal frequency-division multiplexing data symbol adjacent in time to the first orthogonal frequency-division multiplexing data symbol; and demodulating the second orthogonal frequency-division multiplexing data symbol of the set of orthogonal frequency-division multiplexing data symbols based at least in part on the second common phase error mitigation. ### Claim 10 (depends on 7) The method of claim 7, wherein receiving the downlink shared channel message further comprises: receiving the plurality of orthogonal frequency-division multiplexing symbols in the downlink shared channel allocation with an unknown residual carrier frequency offset. ### Claim 11 (depends on 10) The method of claim 10, wherein the downlink shared channel message comprises one of a frequency range one cellular cell message or a frequency range two or above cellular cell message. ### Claim 12 (depends on 3) The method of claim 3, wherein the downlink shared channel message comprises a frequency range two or above cellular message. ### Claim 13 (depends on 1) The method of claim 1, further comprising: transmitting, to the network device, a control message indicating the capability of the UE to apply blind common phase error estimation. ### Claim 14 (depends on 13) The method of claim 13, wherein transmitting the control message comprises: transmitting, with the control message, a first indication of one or more phase tracking reference signal related modulation and coding scheme threshold indices for the downlink shared channel allocation and a second indication of one or more phase tracking reference signal related bandwidth thresholds for the downlink shared channel allocation. ### Claim 15 A method for wireless communications at a network device, comprising: transmitting, to a user equipment (UE), control information scheduling an uplink shared channel allocation for transmitting an uplink shared channel message; transmitting, to the UE, control signaling indicating to omit transmission of a phase tracking reference signal in the uplink shared channel allocation; and receiving the uplink shared channel message in the uplink shared channel allocation in accordance with a phase tracking reference signal configuration that omits a phase tracking reference signal based at least in part on a capability of the network device to apply blind common phase error mitigation for uplink shared channel receptions. ### Claim 16 (depends on 15) The method of claim 15, wherein receiving the uplink shared channel message comprises: receiving the uplink shared channel message conveyed by the uplink shared channel allocation based at least in part on applying the blind common phase error mitigation as a part of an uplink k shared channel allocation demodulation process. ### Claim 17 (depends on 16) The method of claim 16, wherein applying the blind common phase error mitigation comprises: determining a blind common phase error estimation; and applying a blind common phase error correction based at least in part on the blind common phase error estimation. ### Claim 18 (depends on 17) The method of claim 17, further comprising: transmitting, with the control information, scheduling information for a set of uplink shared channel allocations associated with a set of component carriers and without a phase tracking reference signal, wherein the uplink shared channel allocation is associated with a first component carrier; and receiving a set of uplink shared channel messages transmitted simultaneously with the uplink shared channel message via the set of uplink shared channel allocations associated with the set of component carriers based at least in part on the determined blind common phase error estimation for the uplink shared channel message. ### Claim 19 (depends on 15) The method of claim 15, wherein receiving the uplink shared channel message comprises: receiving a plurality of orthogonal frequency-division multiplexing symbols in the uplink shared channel allocation comprising a single demodulation reference signal and a set of orthogonal frequency-division multiplexing data symbols. ### Claim 20 (depends on 19) The method of claim 19, wherein receiving the uplink shared channel message further comprises: applying a first common phase error mitigation to a first orthogonal frequency-division multiplexing data symbol of the set of orthogonal frequency-division multiplexing data symbols, wherein the first orthogonal frequency-division multiplexing data symbol comprises a nearest orthogonal frequency-division multiplexing data symbol to the single demodulation reference signal; and demodulating the first orthogonal frequency-division multiplexing data symbol of the set of orthogonal frequency-division multiplexing data symbols based at least in part on the first common phase error mitigation. ### Claim 21 (depends on 20) The method of claim 20, wherein receiving the uplink shared channel message further comprises: applying a second common phase error mitigation to a second orthogonal frequency-division multiplexing data symbol of the set of orthogonal frequency-division multiplexing data symbols based at least in part on the first common phase error mitigation of the first orthogonal frequency-division multiplexing data symbol, the second orthogonal frequency-division multiplexing data symbol adjacent in time to the first orthogonal frequency-division multiplexing data symbol; and demodulating the second orthogonal frequency-division multiplexing data symbol of the set of orthogonal frequency-division multiplexing data symbols based at least in part on the second common phase error mitigation. ### Claim 22 (depends on 19) The method of claim 19, wherein receiving the uplink shared channel message further comprises: receiving the plurality of orthogonal frequency-division multiplexing symbols in the uplink shared channel allocation with an unknown carrier frequency offset. ### Claim 23 (depends on 22) The method of claim 22, wherein the uplink shared channel message comprises one of a frequency range one cellular cell message or a frequency range two or above cellular cell message. ### Claim 24 (depends on 15) The method of claim 15, wherein the uplink shared channel message comprises a frequency range two or above cellular message. ### Claim 25 An apparatus for wireless communications at a user equipment (UE), comprising: a processor; memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to: receive, from a network device, control signaling indicating parameters for a phase tracking reference signal configuration for a downlink shared channel reception, the parameters indicating to the UE that the phase tracking reference signal configuration omits a phase tracking reference signal based at least in part on a capability of the UE to apply blind common phase error mitigation for downlink shared channel receptions; and receive, from the network device, control information scheduling a downlink shared channel allocation without a phase tracking reference signal. ### Claim 26 (depends on 25) The apparatus of claim 25, wherein the instructions to receive the control signaling are executable by the processor to cause the apparatus to: receive the control signaling via a radio resource control message. ### Claim 27 (depends on 25) The apparatus of claim 25, wherein the instructions are further executable by the processor to cause the apparatus to: receive a downlink shared channel message in the downlink shared channel allocation in accordance with the parameters. ### Claim 28 (depends on 27) The apparatus of claim 27, wherein the instructions to receive the downlink shared channel message are executable by the processor to cause the apparatus to: receive the downlink shared channel message conveyed by the downlink shared channel allocation based at least in part on applying the blind common phase error mitigation as a part of a downlink shared channel allocation demodulation process. ### Claim 29 (depends on 28) The apparatus of claim 28, wherein the instructions to apply the blind common phase error mitigation are executable by the processor to cause the apparatus to: determine a blind common phase error estimation; and apply a blind common phase error correction based at least in part on the blind common phase error estimation. ### Claim 30 An apparatus for wireless communications at a network 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: transmit, to a user equipment (UE), control information scheduling an uplink shared channel allocation for transmitting an uplink shared channel message; transmit, to the UE, control signaling indicating to omit transmission of a phase tracking reference signal in the uplink shared channel allocation; and receive the uplink shared channel message in the uplink shared channel allocation in accordance with a phase tracking reference signal configuration that omits a phase tracking reference signal based at least in part on a capability of the network device to apply blind common phase error mitigation for uplink shared channel receptions.