# US 10,320,475 B2 · Power control in assisted millimeter wave initial access > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,320,475 B2 - Document ID: US10320475B2 - Status: Granted - Kind: B2 - Application number: 15/673,114 - Filed: 2017-08-09 - Published: 2018-04-26 - Granted: 2019-06-11 - Earliest claimed: 2016-10-21 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Navid Abedini; Bilal Sadiq; Sundar Subramanian; Muhammad Nazmul Islam; Junyi Li - Web page: https://patentgrep.com/patent/US10320475B2 ## CPC - H04B 7/2684: {Synchronisation of a mobile station with more than one base station} - H04B 7/0426: Power distribution - H04B 7/0617: {for beam forming} - H04B 7/0623: {Auxiliary parameters, e.g. power control [PCB] or not acknowledged commands [NACK], used as feedback information} - H04B 7/0814: {based on current reception conditions, e.g. switching to different antenna when signal level is below threshold} - H04B 7/0834: {based on external parameters, e.g. subscriber speed or location} - H04B 7/2606: {Arrangements for base station coverage control, e.g. by using relays in tunnels} - H04W 16/28: using beam steering - H04W 52/146: {Uplink power control} - H04W 52/50: at the moment of starting communication in a multiple access environment - H04W 52/283: {Power depending on the position of the mobile} - H04W 52/325: {Power control of control or pilot channels} - H04W 52/367: {Power values between minimum and maximum limits, e.g. dynamic range} - H04W 52/42: in systems with time, space, frequency or polarisation diversity - H04W 74/0833: Random access procedures, e.g. with 4-step access - H04W 76/10: Connection setup - 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 assisted power control for an uplink signal transmitted during a RACH procedure. A UE may determine a transmit power for transmitting a message during a RACH procedure with a secondary BS, based at least in part, on communication between the UE and a primary BS. The UE may transmit the message to the second BS during the RACH procedure based, at least in part, on the determined transmit power. ## Claims ### Claim 1 A method for wireless communication by a user equipment (UE), comprising: determining a transmit power for transmitting a message during a random access channel (RACH) procedure with a first base station (BS), based at least in part, on communication between the UE and a second BS by transmitting a reference signal (RS) to the second BS and receiving a directional synchronization signal from the first BS in response to the RS, wherein the transmit power is based, at least in part, on the received directional synchronization signal, wherein the first BS operates in a millimeter wave (mmWave) spectrum and the second BS operates in a different frequency spectrum; transmitting the message to the first BS during the RACH procedure based, at least in part, on the determined transmit power. ### Claim 2 (depends on 1) The method of claim 1, wherein the first and second BSs comprise co-located BSs. ### Claim 3 (depends on 1) The method of claim 1, wherein the message comprises a directional RACH preamble transmission. ### Claim 4 (depends on 1) The method of claim 1, further comprising: determining a proximity level to the first BS based, at least in part, on the communication with the second BS, wherein the transmit power is set based, at least in part, on the determined proximity level. ### Claim 5 (depends on 4) The method of claim 4, further comprising: determining the proximity level to the first BS is below a threshold value; and in response to the determining the proximity level to the first BS is below the threshold value, setting the transmit power to less than a maximum transmit power. ### Claim 6 (depends on 4) The method of claim 4, further comprising: determining a location of the UE based, at least in part, on any combination of a global positional system (GPS) position, and a positioning service provided by the second BS, wherein determining the proximity level to the first BS is based, at least in part, based on the determined location of the UE. ### Claim 7 (depends on 1) The method of claim 1, further comprising: receiving a reference signal (RS) from the second BS; and calculating a reference signal receive power (RSRP) associated with the RS, wherein the transmit power is set based, at least in part, on the RSRP. ### Claim 8 (depends on 7) The method of claim 7, wherein determining the transmit power further comprises: comparing the RSRP of the RS to at least one threshold value; and in response to the comparison, selecting the transmit power from a set of predetermined values. ### Claim 9 (depends on 1) The method of claim 1, wherein determination of the transmit power is further based on an indication of the transmit power received from the second BS. ### Claim 10 (depends on 9) The method of claim 9, further comprising: transmitting a reference signal (RS) to the second BS, wherein the indication of the transmit power received from the second BS is based on a reference signal receive power (RSRP) associated with the transmitted RS. ### Claim 11 (depends on 1) The method of claim 1, wherein determining the transmit power further comprises: determining a distance between the UE and the first BS is less than a threshold distance; and in response to the determination, transmitting a request to the first BS, via the second BS, for the directional synchronization signal. ### Claim 12 (depends on 1) The method of claim 1, further comprising: receiving, from the second BS, an indication of at least one of a configuration of the directional synchronization signal or resources used for transmission of the directional synchronization signal, wherein the directional synchronization signal is received based, at least in part, on the indication. ### Claim 13 A method for wireless communication by a first base station (BS), comprising: communicating with a user equipment (UE); and taking one or more actions to assist the UE in setting a transmit power for transmitting a message during a random access channel (RACH) procedure with a second BS, based at least in part, on the communication between the UE and the first BS, wherein taking the one or more actions comprises receiving a first request, from the UE, for a directional synchronization signal from the second BS, and in response to the first request, transmitting, to the second BS, a second request for the directional synchronization signal, wherein the second BS operates in a millimeter wave (mmWave) spectrum and the first BS operates in a different frequency spectrum. ### Claim 14 (depends on 13) The method of claim 13, wherein the first and second BSs comprise co-located BSs. ### Claim 15 (depends on 13) The method of claim 13, wherein taking the one or more actions further comprises: transmitting a reference signal (RS) to the UE, wherein the transmit power is based, at least in part, on a reference signal receive power (RSRP) associated with the RS. ### Claim 16 (depends on 13) The method of claim 13, wherein taking the one or more actions further comprises: transmitting an indication of the transmit power for transmitting the message during the RACH procedure. ### Claim 17 (depends on 13) The method of claim 13, wherein taking the one or more actions further comprises: receiving a reference signal (RS) from the UE; calculating a reference signal receive power (RSRP) associated with the RS; and determining the transmit power for transmitting the message during the RACH procedure, based, at least in part, on the RSRP. ### Claim 18 (depends on 17) The method of claim 17, wherein determining the transmit power comprises: comparing the RSRP of the RS to at least one threshold value; and in response, selecting the transmit power from a set of predetermined values. ### Claim 19 (depends on 13) The method of claim 13, wherein taking the one or more further actions comprises: determining a distance between the UE and the second BS is less than a threshold value; and in response to the determining, transmitting, to the second BS, a request for the directional synchronization signal. ### Claim 20 (depends on 19) The method of claim 19, further comprising: determining information associated with the directional synchronization signal transmitted by the second BS, wherein the information indicates at least one of a configuration of the directional synchronization signal or resources used for transmission of the directional synchronization signal; and transmitting, to the UE, a message indicating the information. ### Claim 21 (depends on 19) The method of claim 19, further comprising: receiving a reference signal (RS) from the UE; and determining a reference signal received power (RSRP) associated with the received RS, wherein the distance between the UE and the second BS is determined based, at least in part, on the RSRP. ### Claim 22 An apparatus for wireless communication by a user equipment (UE), comprising at least one processor and memory coupled to the at least one processor, wherein the at least one processor is configured to: determine a transmit power for transmitting a message during a random access channel (RACH) procedure with a first base station (BS), based at least in part, on communication between the UE and a second BS by transmitting a reference signal (RS) to the second BS and receiving a directional synchronization signal from the first BS in response to the RS, wherein the transmit power is based, at least in part, on the received directional synchronization signal, wherein the first BS operates in a millimeter wave (mmWave) spectrum and the second BS operates in a different frequency spectrum; transmit the message to the first BS during the RACH procedure based, at least in part, on the determined transmit power. ### Claim 23 (depends on 22) The apparatus of claim 22, wherein the message comprises a directional RACH preamble transmission. ### Claim 24 (depends on 22) The apparatus of claim 22, wherein the at least one processor is configured to: determine a proximity level to the first BS based, at least in part, on the communication with the second BS, wherein the transmit power is set based, at least in part, on the determined proximity level. ### Claim 25 An apparatus for wireless communication by a first base station (BS), comprising at least one processor and memory coupled to the at least one processor, wherein the at least one processor is configured to: communicate with a user equipment (UE); and take one or more actions to assist the UE in setting a transmit power for transmitting a message during a random access channel (RACH) procedure with a second BS, based at least in part, on the communication between the UE and the first BS, wherein taking the one or more actions comprises receiving a first request, from the UE, for a directional synchronization signal from the second BS, and in response to the first request, transmitting, to the second BS, a second request for the directional synchronization signal, wherein the second BS operates in a millimeter wave (mmWave) spectrum and the first BS operates in a different frequency spectrum. ### Claim 26 (depends on 25) The apparatus of claim 25, wherein taking the one or more actions comprises: transmitting an indication of the transmit power for transmitting the message during the RACH procedure.