# US 12,225,480 B2 · Power headroom reporting over sidelinks > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,225,480 B2 - Document ID: US12225480B2 - Status: Granted - Kind: B2 - Application number: 17/468,313 - Filed: 2021-09-07 - Published: 2023-03-09 - Granted: 2025-02-11 - Earliest claimed: 2021-09-07 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Lik Hang Silas Fong; Piyush Gupta; Juan Montojo - Web page: https://patentgrep.com/patent/US12225480B2 ## CPC - H04W 52/365: {Power headroom reporting} - H04W 52/14: Separate analysis of uplink or downlink - H04W 52/247: {where the output power of a terminal is based on a path parameter sent by another terminal} - H04W 52/248: {where transmission power control commands are generated based on a path parameter} - H04W 52/367: {Power values between minimum and maximum limits, e.g. dynamic range} - H04W 52/383: {power control in peer-to-peer links} - H04W 80/02: Data link layer protocols - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Aspects of the present disclosure provide techniques that may help enhance power control for sidelink transmissions. According to certain aspects, a method for wireless communications by a first user equipment (UE) generally includes transmitting a power headroom report (PHR) to a second UE, receiving, from the second UE, a transmit power control (TPC) based on the PHR, and transmitting at least a first sidelink transmission to the second UE with transmit power in accordance with the TPC. ## Claims ### Claim 1 A method for wireless communications by a first user equipment (UE), comprising: transmitting a power headroom report (PHR) to a second UE, wherein the PHR is transmitted via a PHR medium access control (MAC) control element (CE) over a sidelink, wherein transmitting the PHR comprises transmitting at least a first PHR for a first type of sidelink transmission and a second PHR for a second type of sidelink transmission via the PHR MAC CE, wherein the first type of sidelink transmission comprises a physical sidelink shared channel (PSSCH), and wherein the second type of sidelink transmission comprises a physical sidelink feedback channel (PSFCH); receiving, from the second UE, a transmit power control (TPC) based on the PHR; and transmitting at least a first sidelink transmission to the second UE with transmit power in accordance with the TPC. ### Claim 2 (depends on 1) The method of claim 1, wherein: the PHR indicates a power headroom that represents a difference between a nominal maximum transmit power of the first UE and an estimated power for the first sidelink transmission; and the PHR MAC CE comprises an indication of the nominal maximum transmit power. ### Claim 3 (depends on 2) The method of claim 2, wherein at least one of the power headroom or the normal maximum transmit power is indicated via a bit map. ### Claim 4 (depends on 3) The method of claim 3, further comprising receiving sidelink radio resource control (RRC) signaling from the second UE indicating the bit map for the at least one of the power headroom or the normal maximum transmit power. ### Claim 5 (depends on 1) The method of claim 1, wherein the PHR is transmitted when one or more trigger conditions are met. ### Claim 6 (depends on 5) The method of claim 5, further comprising receiving sidelink radio resource control (RRC) signaling from the second UE indicating one or more parameters related to the trigger conditions. ### Claim 7 (depends on 6) The method of claim 6, wherein the one or more parameters comprise at least one of: a periodic timer related to a trigger condition that the periodic timer expire to trigger transmission of the PHR; a prohibit timer related to a trigger condition that the first UE is prohibited from transmitting the PHR until the prohibit timer has expired; or a threshold change related to a trigger condition that the first UE is triggered to transmit the PHR when a difference between a previously reported power headroom and a current power headroom is greater than the threshold change. ### Claim 8 (depends on 1) The method of claim 1, wherein the MAC CE includes a logical channel identifier (LCID) indicating the MAC CE includes multiple PHRs. ### Claim 9 (depends on 1) The method of claim 1, wherein: the first UE comprises at least one of a at least one of a sensor or an actuator; and the second UE comprises a programmable logic controller (PLC). ### Claim 10 A method for wireless communications by a second user equipment (UE), comprising: receiving a power headroom report (PHR) from a first UE, wherein the PHR is received via a PHR medium access control (MAC) control element (CE) over a sidelink, wherein receiving the PHR comprises receiving at least a first PHR for a first type of sidelink transmission and a second PHR for a second type of sidelink transmission via the PHR MAC CE, wherein the first type of sidelink transmission comprises a physical sidelink shared channel (PSSCH), and wherein the second type of sidelink transmission comprises a physical sidelink feedback channel (PSFCH); transmitting, to the first UE, a transmit power control (TPC) based on the PHR; and receiving at least a first sidelink transmission from the first UE after transmitting the TPC. ### Claim 11 (depends on 10) The method of claim 10, wherein: the PHR indicates a power headroom that represents a difference between a nominal maximum transmit power of the first UE and an estimated power for the first sidelink transmission; and the PHR MAC CE comprises an indication of the nominal maximum transmit power. ### Claim 12 (depends on 11) The method of claim 11, wherein at least one of the power headroom or the normal maximum transmit power is indicated via a bit map. ### Claim 13 (depends on 12) The method of claim 12, further comprising transmitting sidelink radio resource control (RRC) signaling to the first UE indicating the bit map for the at least one of the power headroom or the normal maximum transmit power. ### Claim 14 (depends on 10) The method of claim 10, wherein the PHR is received when one or more trigger conditions are met. ### Claim 15 (depends on 14) The method of claim 14, further comprising transmitting sidelink radio resource control (RRC) signaling to the first UE indicating one or more parameters related to the trigger conditions. ### Claim 16 (depends on 15) The method of claim 15, wherein the one or more parameters comprise at least one of: a periodic timer related to a trigger condition that the periodic timer expire to trigger transmission of the PHR; a prohibit timer related to a trigger condition that the first UE is prohibited from transmitting the PHR until the prohibit timer has expired; or a threshold change related to a trigger condition that the first UE is triggered to transmit the PHR when a difference between a previously reported power headroom and a current power headroom is greater than the threshold change. ### Claim 17 (depends on 10) The method of claim 10, wherein the MAC CE includes a logical channel identifier (LCID) indicating the MAC CE includes multiple PHRs. ### Claim 18 (depends on 10) The method of claim 10, wherein: the first UE comprises at least one of a at least one of a sensor or an actuator; and the second UE comprises a programmable logic controller (PLC). ### Claim 19 A first user equipment (UE) comprising at least one processor and a memory configured to: transmit a power headroom report (PHR) to a second UE, wherein the PHR is transmitted via a PHR medium access control (MAC) control element (CE) over a sidelink, wherein transmitting the PHR comprises transmitting at least a first PHR for a first type of sidelink transmission and a second PHR for a second type of sidelink transmission via the PHR MAC CE, wherein the first type of sidelink transmission comprises a physical sidelink shared channel (PSSCH), and wherein the second type of sidelink transmission comprises a physical sidelink feedback channel (PSFCH); receive, from the second UE, a transmit power control (TPC) based on the PHR; and transmit at least a first sidelink transmission to the second UE with transmit power in accordance with the TPC. ### Claim 20 A second user equipment (UE) comprising at least one processor and a memory configured to: receive a power headroom report (PHR) from a first UE, wherein the PHR is received via a PHR medium access control (MAC) control element (CE) over a sidelink, wherein receiving the PHR comprises receiving at least a first PHR for a first type of sidelink transmission and a second PHR for a second type of sidelink transmission via the PHR MAC CE, wherein the first type of sidelink transmission comprises a physical sidelink shared channel (PSSCH), and wherein the second type of sidelink transmission comprises a physical sidelink feedback channel (PSFCH); transmit, to the first UE, a transmit power control (TPC) based on the PHR; and receive at least a first sidelink transmission from the first UE after transmitting the TPC.