# US 12,003,305 B2 · Initial acquisition and beam refinement from an intelligent reflecting surface using defocused beams > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,003,305 B2 - Document ID: US12003305B2 - Status: Granted - Kind: B2 - Application number: 17/402,463 - Filed: 2021-08-13 - Published: 2023-02-16 - Granted: 2024-06-04 - Earliest claimed: 2021-08-13 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Mehmet Izzet Gurelli; Qiang Wu; Junyi Li; Raju Hormis; Tao Luo; Navid Abedini; Ozge Koymen; Farideddin Fayazbakhsh - Web page: https://patentgrep.com/patent/US12003305B2 ## CPC - H04B 7/06958: {Multistage beam selection, e.g. beam refinement} - H04B 7/0408: using two or more beams, i.e. beam diversity - H04B: TRANSMISSION ## Abstract A base station may identify one or more beams toward a node for communication with at least one UE. The one or more beams may correspond to a plurality of beams from the node. The base station may transmit, to the node, an indication to adjust a surface phase of the node corresponding to the one or more beams or one of the plurality of beams from the node. The base station may select at least one beam of the plurality of beams from the node for communication with the at least one UE. The base station may communicate with the at least one UE via the node and the at least one beam. The at least one beam of the plurality of beams from the node may be based on a defocusing operation associated with a virtual focal point. ## Claims ### Claim 1 An apparatus for wireless communication at a base station, comprising: a memory; and at least one processor coupled to the memory and configured to: identify one or more beams toward a node for communication with at least one user equipment (UE), the one or more beams corresponding to a plurality of beams from the node; transmit, to the node, an indication to adjust a surface phase of the node corresponding to the one or more beams or one of the plurality of beams from the node; select at least one beam of the plurality of beams from the node for communication with the at least one UE, the at least one beam being selected based on a defocusing operation in connection with a virtual focal point and at least one of: an azimuth or an elevation of the at least one beam, a random access channel (RACH) message from the at least one UE, a reference signal received power (RSRP) measurement of the at least one beam, or a width or a height of an enabled surface area of the node; and transmit, to the at least one UE via the node, or receive, from the at least one UE via the node, communication via the at least one beam. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein the one or more beams correspond to at least one of a synchronization signal block (SSB) beam, a channel state information (CSI)— reference signal (RS) (CSI-RS), or a sounding reference signal (SRS). ### Claim 3 (depends on 1) The apparatus of claim 1, wherein the node is an intelligent reflective surface (IRS). ### Claim 4 (depends on 1) The apparatus of claim 1, wherein the indication to adjust the surface phase of the node is a control signal. ### Claim 5 (depends on 1) The apparatus of claim 1, the processor being further configured to: receive, from the at least one UE via the node, the RACH message, wherein the selected at least one beam corresponding to the RACH message corresponds to a starting candidate beam. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein the at least one beam is selected from the plurality of beams from the node based on an iterative process, and in each iteration of the iterative process, the at least one processor is further configured to: select one refined beam from a plurality of candidate refined beams based on RSRP measurements associated with the plurality of candidate refined beams, wherein the selected one refined beam is associated with a highest RSRP measurement, each of the plurality of candidate refined beams is associated with a smaller angular spread than a starting candidate beam of the plurality of beams from the node or a selected refined beam from a previous iteration, and each of the plurality of candidate refined beams is associated with a coverage area that is inside a coverage area of the starting candidate beam or the selected refined beam from the previous iteration. ### Claim 7 (depends on 6) The apparatus of claim 6, wherein the at least one beam is selected based further on a focusing at infinity operation associated with a selected refined beam from a last iteration. ### Claim 8 (depends on 1) The apparatus of claim 1, the at least one processor being further configured to: configure the node to perform the defocusing operation based on the indication to adjust the surface phase of the node. ### Claim 9 (depends on 8) The apparatus of claim 8, wherein to configure the node to perform the defocusing operation, the at least one processor is further configured to: set a width of the at least one beam of the plurality of beams based on at least one of a radial distance of the virtual focal point from the node or the width of the enabled surface area of the node. ### Claim 10 (depends on 8) The apparatus of claim 8, wherein to configure the node to perform the defocusing operation, the at least one processor is further configured to: set an azimuth or an elevation of the at least one beam of the plurality of beams based on an azimuth or an elevation of the virtual focal point. ### Claim 11 (depends on 8) The apparatus of claim 8, wherein to configure the node to perform the defocusing operation, the at least one processor is further configured to: configure the node to defocus the at least one beam of the plurality of beams in both azimuth and elevation. ### Claim 12 (depends on 8) The apparatus of claim 8, wherein to configure the node to perform the defocusing operation, the at least one processor is further configured to: configure the node to defocus the at least one beam of the plurality of beams in one of azimuth or elevation; and configure the node to focus the at least one beam of the plurality of beams in the other of azimuth or elevation. ### Claim 13 (depends on 1) The apparatus of claim 1, the at least one processor being further configured to: identify, via the selected at least one beam of the plurality of beams from the node, a radial distance of the at least one UE from the node based on a channel estimation procedure; and configure the node to adjust the selected at least one beam based on the identified radial distance of the at least one UE from the node. ### Claim 14 (depends on 1) The apparatus of claim 1, further comprising a transceiver coupled to the at least one processor. ### Claim 15 A method of wireless communication at a base station, comprising: identifying one or more beams toward a node for communication with at least one user equipment (UE), the one or more beams corresponding to a plurality of beams from the node; transmitting, to the node, an indication to adjust a surface phase of the node corresponding to the one or more beams or one of the plurality of beams from the node; selecting at least one beam of the plurality of beams from the node for communication with the at least one UE, the at least one beam being selected based on a defocusing operation in connection with a virtual focal point and at least one of: an azimuth or an elevation of the at least one beam, a random access channel (RACH) message from the at least one UE, a reference signal received power (RSRP) measurement of the at least one beam, or a width or a height of an enabled surface area of the node; and transmitting, to the at least one UE via the node, or receiving, from the at least one UE via the node, communication via the at least one beam. ### Claim 16 An apparatus for wireless communication at a node, comprising: a memory; and at least one processor coupled to the memory and configured to: receive, from a base station, an indication to adjust a surface phase of the node corresponding to one or more beams toward the node or at least one of a plurality of beams from the node for communication with at least one user equipment (UE), the one or more beams corresponding to the plurality of beams; and send, via the at least one beam of the plurality of beams, communication from the base station to the at least one UE or communication from the at least one UE to the base station, the at least one beam being based on a defocusing operation in connection with a virtual focal point and at least one of: an azimuth or an elevation of the at least one beam, a random access channel (RACH) message from the UE, a reference signal received power (RSRP) measurement of the at least one beam, or a width or a height of an enabled surface area of the node. ### Claim 17 (depends on 16) The apparatus of claim 16, wherein the one or more beams correspond to at least one of a synchronization signal block (SSB) beam, a channel state information (CSI)—reference signal (RS) (CSI-RS), or a sounding reference signal (SRS). ### Claim 18 (depends on 16) The apparatus of claim 16, wherein the node is an intelligent reflective surface (IRS). ### Claim 19 (depends on 16) The apparatus of claim 16, the at least one processor being further configured to: send, from the at least one UE to the base station, the RACH message, wherein the at least one beam corresponding to the RACH message corresponds to a starting candidate beam. ### Claim 20 (depends on 16) The apparatus of claim 16, wherein to send the communication from the base station to the at least one UE or the communication from the at least one UE to the base station, the at least one processor is further configured to: reflect or forward the communication from the base station to the at least one UE or the communication from the at least one UE to the base station. ### Claim 21 (depends on 16) The apparatus of claim 16, wherein the at least one beam is selected from the plurality of beams from the node based on an iterative process, and in each iteration of the iterative process, one refined beam is selected from a plurality of candidate refined beams based on RSRP measurements associated with the plurality of candidate refined beams, wherein the selected one refined beam is associated with a highest RSRP measurement, each of the plurality of candidate refined beams is associated with a smaller angular spread than a starting candidate beam of the plurality of beams from the node or a selected refined beam from a previous iteration, and each of the plurality of candidate refined beams is associated with a coverage area that is inside a coverage area of the starting candidate beam or the selected refined beam from the previous iteration. ### Claim 22 (depends on 21) The apparatus of claim 21, wherein the at least one beam is based further on a focusing at infinity operation associated with a selected refined beam from a last iteration. ### Claim 23 (depends on 21) The apparatus of claim 21, wherein the starting candidate beam and the plurality of candidate refined beams in each iteration are each based on the defocusing operation in connection with the virtual focal point, and the defocusing operation is based on the indication to adjust the surface phase of the node. ### Claim 24 (depends on 16) The apparatus of claim 16, wherein in the defocusing operation, the at least one processor is configured to: set a width of the at least one beam based on at least one of a radial distance of the virtual focal point from the node or the width of the enabled surface area of the node. ### Claim 25 (depends on 16) The apparatus of claim 16, wherein in the defocusing operation, the at least one processor is configured to: set an azimuth or an elevation of the at least one beam based on an azimuth or an elevation of the virtual focal point. ### Claim 26 (depends on 16) The apparatus of claim 16, wherein in the defocusing operation, the at least one processor is configured to: defocus the at least one beam in both azimuth and elevation. ### Claim 27 (depends on 16) The apparatus of claim 16, wherein in the defocusing operation, the at least one processor is configured to: defocus the at least one beam in one of azimuth or elevation; and focus the at least one beam in the other of azimuth or elevation. ### Claim 28 (depends on 16) The apparatus of claim 16, wherein the at least one beam is based further on a radial distance of the at least one UE from the node. ### Claim 29 (depends on 16) The apparatus of claim 16, further comprising a transceiver coupled to the at least one processor. ### Claim 30 A method of wireless communication at a node, comprising: receiving, from a base station, an indication to adjust a surface phase of the node corresponding to one or more beams toward the node or at least one of a plurality of beams from the node for communication with at least one user equipment (UE), the one or more beams corresponding to the plurality of beams; and sending, via the at least one beam of the plurality of beams, communication from the base station to the at least one UE or communication from the at least one UE to the base station, the at least one beam being based on a defocusing operation in connection with a virtual focal point and at least one of: an azimuth or an elevation of the at least one beam, a random access channel (RACH) message from the UE, a reference signal received power (RSRP) measurement of the at least one beam, or a width or a height of an enabled surface area of the node.