# US 10,484,875 B2 · Techniques for transmission of sounding reference signal in shared radio frequency spectrum band > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,484,875 B2 - Document ID: US10484875B2 - Status: Granted - Kind: B2 - Application number: 15/392,290 - Filed: 2016-12-28 - Published: 2017-07-06 - Granted: 2019-11-19 - Earliest claimed: 2015-12-30 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Wanshi Chen; Peter Gaal - Web page: https://patentgrep.com/patent/US10484875B2 ## CPC - H04W 16/14: Spectrum sharing arrangements {between different networks} - H04L 5/001: {the frequencies being arranged in component carriers} - 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)} - H04W 52/30: using constraints in the total amount of available transmission power - H04W 72/0446: Resources in time domain, e.g. slots or frames - H04W 72/0453: Resources in frequency domain, e.g. a carrier in FDMA - H04W 72/21: in the uplink direction of a wireless link, i.e. towards the network - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Sounding reference signal (SRS) transmissions in a shared RF spectrum band, alone or in conjunction with a dedicated RF spectrum band, may be transmitted using two or more uplink component carriers (CCs). A UE may identify that the two or more CCs are in a same timing advance group (TAG), and transmit a SRS transmission and a physical uplink shared channel (PUSCH) or physical uplink control channel (PUCCH) transmission during a same uplink symbol. A UE may transmit a SRS based on a minimum configured power in the event that the UE is power limited during a SRS transmission symbol. A channel priority assigned to a CC carrying a SRS transmission in a shared RF spectrum band may be set to a higher channel priority than a channel priority for a similar transmission using a dedicated RF spectrum band. ## Claims ### Claim 1 A method for wireless communication at a user equipment (UE), comprising: establishing wireless communications using two or more uplink component carriers (CCs) in a wireless communications network, wherein a first uplink CC of the two or more uplink CCs uses a shared radio frequency (RF) spectrum band that is available for unlicensed use; identifying that each of the two or more uplink CCs are configured to be in a same timing advance group (TAG); identifying a sounding reference signal (SRS) to be transmitted in a first symbol using the first uplink CC of the two or more uplink CCs; determining that one or more of a physical uplink shared channel (PUSCH) transmission or a physical uplink control channel (PUCCH) transmission is to be transmitted in the first symbol using a second uplink CC of the two or more uplink CCs; determining that the transmission during the first symbol using the two or more uplink CCs is power limited; and transmitting the SRS in the first symbol, using a minimum guaranteed power level configured for transmission of the first uplink CC, using the first uplink CC, and transmitting one or more of the PUSCH or PUCCH using the second uplink CC. ### Claim 2 (depends on 1) The method of claim 1, wherein the transmitting further comprises: dropping the transmission of the SRS. ### Claim 3 (depends on 1) The method of claim 1, wherein the transmitting further comprises: transmitting the SRS during a regular uplink subframe of a radio frame. ### Claim 4 (depends on 1) The method of claim 1, wherein the transmitting further comprises: transmitting the SRS during a special subframe of a radio frame. ### Claim 5 (depends on 4) The method of claim 4, wherein the transmitting further comprises: transmitting two or more SRS symbols during an uplink pilot time slot (UpPTS) of the special subframe. ### Claim 6 (depends on 1) The method of claim 1, wherein the transmitting further comprises: transmitting the SRS using the first uplink CC over the shared RF spectrum band using a channel priority that is different than a channel priority for transmitting the SRS using a CC over a dedicated RF spectrum band. ### Claim 7 (depends on 1) The method of claim 1, wherein the transmitting further comprises: formatting the SRS to span a frequency bandwidth of the first symbol. ### Claim 8 (depends on 7) The method of claim 7, wherein the formatting is based at least in part on a power spectral density limit of the frequency bandwidth. ### Claim 9 (depends on 1) The method of claim 1, wherein the two or more uplink CCs comprise a first set of uplink CCs that are allocated for uplink transmissions during a transmission time interval (TTI), and wherein the transmitting further comprises: transmitting one or more of the PUCCH transmission or PUSCH transmission using the first set of uplink CCs; and transmitting the SRS using a different uplink CC that is outside of the first set of uplink CCs. ### Claim 10 (depends on 9) The method of claim 9, wherein the different uplink CC is a CC associated with a second set of downlink CCs, and wherein the first set of uplink CCs comprise fewer CCs than the second set of downlink CCs. ### Claim 11 (depends on 1) The method of claim 1, wherein the first uplink CC and the second uplink CC are different CCs. ### Claim 12 A method for wireless communication at a base station, comprising: configuring wireless communications at a user equipment (UE) using two or more uplink component carriers (CCs) in a wireless communications network, wherein a first uplink CC of the two or more uplink CCs uses a shared radio frequency (RF) spectrum band that is available for unlicensed use; configuring each of the two or more uplink CCs to be in a same timing advance group (TAG); and configuring a sounding reference signal (SRS) to be transmitted in a first symbol, based at least in part on a minimum guaranteed power level that is to be used when transmitting using the first uplink CC, using the first uplink CC of the two or more uplink CCs concurrently with one or more of a physical uplink shared channel (PUSCH) transmission or a physical uplink control channel (PUCCH) transmission to be transmitted during the first symbol using a second uplink CC of the two or more uplink CCs. ### Claim 13 (depends on 12) The method of claim 12, wherein the configuring the SRS to be transmitted further comprises: configuring the SRS to be transmitted during a regular uplink subframe of a radio frame. ### Claim 14 (depends on 12) The method of claim 12, wherein the configuring the SRS to be transmitted further comprises: configuring the SRS to be transmitted during a special subframe of a radio frame. ### Claim 15 (depends on 14) The method of claim 14, wherein the configuring further comprises: configuring one or more SRS symbols to be transmitted during an uplink pilot time slot (UpPTS) of the special subframe. ### Claim 16 (depends on 12) The method of claim 12, wherein the configuring the SRS to be transmitted further comprises: configuring the first uplink CC to be transmitted over the shared RF spectrum band using a channel priority that is different than a channel priority for transmitting the second uplink CC to be transmitted over a dedicated RF spectrum band. ### Claim 17 (depends on 12) The method of claim 12, wherein the configuring the SRS to be transmitted further comprises: configuring the SRS to span a frequency bandwidth of the first symbol. ### Claim 18 (depends on 17) The method of claim 17, wherein the frequency bandwidth for the SRS is configured based at least in part on a power spectral density limit of the frequency bandwidth. ### Claim 19 (depends on 12) The method of claim 12, further comprising: allocating a first set of uplink CCs that includes the two or more uplink CCs for uplink transmissions during a transmission time interval (TTI); transmitting downlink transmissions using a second set of downlink CCs that includes different CCs than the first set of uplink CCs; and wherein the configuring the SRS to be transmitted further comprises configuring the SRS to be transmitted using a CC of the second set of downlink CCs that is outside of the first set of uplink CCs. ### Claim 20 (depends on 12) The method of claim 12, wherein the first uplink CC and the second uplink CC are different CCs. ### Claim 21 An apparatus for wireless communication, comprising: a processor; memory in electronic communication with the processor; and instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to: establish wireless communications using two or more uplink component carriers (CCs) in a wireless communications network, wherein a first uplink CC of the two or more uplink CCs uses a shared radio frequency (RF) spectrum band that is available for unlicensed use; identify that each of the two or more uplink CCs are configured to be in a same timing advance group (TAG); identify a sounding reference signal (SRS) to be transmitted in a first symbol using the first uplink CC of the two or more uplink CCs; determine that one or more of a physical uplink shared channel (PUSCH) transmission or a physical uplink control channel (PUCCH) transmission is to be transmitted in the first symbol using a second uplink CC of the two or more uplink CCs; determine that the transmission during the first symbol using the two or more uplink CCs is power limited; transmit the SRS in the first symbol, using a minimum guaranteed power level configured for transmission of the first uplink CC, using the first uplink CC, and transmit one or more of the PUSCH or PUCCH using the second uplink CC. ### Claim 22 An apparatus for wireless communication, comprising: a processor; memory in electronic communication with the processor; and instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to: configure wireless communications at a user equipment (UE) using two or more uplink component carriers (CCs) in a wireless communications network, wherein a first uplink CC of the two or more uplink CCs uses a shared radio frequency (RF) spectrum band that is available for unlicensed use; configure each of the two or more uplink CCs to be in a same timing advance group (TAG); and configure a sounding reference signal (SRS) to be transmitted in a first symbol, based at least in part on a minimum guaranteed power level configured for transmission of the first uplink CC, using the first uplink CC of the two or more uplink CCs concurrently with one or more of a physical uplink shared channel (PUSCH) transmission or a physical uplink control channel (PUCCH) transmission to be transmitted during the first symbol using a second uplink CC of the two or more uplink CCs.