# US 12,603,688 B2 · Spatial filter correspondence and random access procedures for reconfigurable intelligent surfaces > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,603,688 B2 - Document ID: US12603688B2 - Status: Granted - Kind: B2 - Application number: 18/025,816 - Filed: 2020-11-06 - Published: 2023-11-09 - Granted: 2026-04-14 - Earliest claimed: 2020-11-06 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Hung Dinh Ly; Yu Zhang; Krishna Kiran Mukkavilli - Web page: https://patentgrep.com/patent/US12603688B2 ## CPC - H04B 7/06952: {Selecting one or more beams from a plurality of beams, e.g. beam training, management or sweeping} - H04B 7/04013: {Intelligent reflective surfaces} - H04W 56/001: {Synchronization between nodes} - H04W 74/0833: Random access procedures, e.g. with 4-step access - 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 Example implementations include a method, apparatus and computer-readable medium of wireless communication to be performed by a user equipment (UE), comprising receiving, from a base station, a synchronization signal block (SSB) via a reconfigurable intelligent surface (RIS), the SSB corresponding to a first SSB type configured for RIS-assisted procedures. The implementations further include performing, with the base station according to the SSB, a random access channel (RACH) procedure. Additionally, the implementations further include transmitting, to the base station according to the SSB, an indication that the SSB corresponds to the first SSB type as part of the RACH procedure. ## Claims ### Claim 1 A method of wireless communication to be performed by a user equipment (UE), comprising: receiving, from a base station, a synchronization signal block (SSB) via a reconfigurable intelligent surface (RIS), the SSB corresponding to a first SSB type configured for RIS-assisted procedures or corresponding to a second SSB type configured for non-RIS-assisted procedures; determining, based on the SSB, whether the RIS-assisted procedures are needed; and transmitting, to the base station according to the SSB, an indication whether the SSB corresponds to the first SSB type as part of a random access channel (RACH) procedure, wherein the first SSB type indicates that the RIS-assisted procedures are needed. ### Claim 2 (depends on 1) The method of claim 1, wherein: receiving the SSB corresponding to the first SSB type configured for the RIS-assisted procedures comprises receiving the SSB reflected by the RIS on a receive spatial filter of the UE, the SSB having been transmitted at multiple SSB resources using a same transmit spatial filter of the base station; and wherein the method further comprises transmitting, to the base station, a physical random access channel (PRACH) on a transmit spatial filter of the UE, wherein the transmit spatial filter of the UE corresponds to the receive spatial filter of the UE that received the SSB. ### Claim 3 (depends on 1) The method of claim 1, further comprising: obtaining a mapping between RACH occasions (ROs) and SSB types; selecting a RO according to the SSB and the mapping, the RO indicating that the SSB corresponds to the first SSB type; and transmitting, to the base station, a physical random access channel (PRACH) using the RO. ### Claim 4 (depends on 1) The method of claim 1, further comprising: obtaining a set of physical random access channel (PRACH) preambles; selecting a PRACH preamble from the set of PRACH preambles, the selected PRACH preamble indicating that the SSB corresponds to the first SSB type; and transmitting, to the base station, a PRACH comprising the selected PRACH preamble. ### Claim 5 (depends on 1) The method of claim 1, further comprising: transmitting, to the base station, a physical uplink shared channel (PUSCH) carrying the indication that the SSB corresponds to the first SSB type, wherein: a demodulation reference signal of the PUSCH indicates that the SSB corresponds to the first SSB type; or a scrambling code of the PUSCH indicates that the SSB corresponds to the first SSB type; or a payload of the PUSCH comprises the indication that the SSB corresponds to the first SSB type. ### Claim 6 (depends on 1) The method of claim 1, further comprising: selecting a physical uplink shared channel (PUSCH) occasion indicating that the SSB corresponds to the first SSB type; and transmitting, to the base station, a PUSCH on the PUSCH occasion. ### Claim 7 (depends on 1) The method of claim 1, further comprising: obtaining a first mapping between first RACH occasions (ROs) and first SSBs, the first SSBs corresponding to the first SSB type; and obtaining a second mapping between second ROs and second SSBs, the second SSBs corresponding to the second SSB type. ### Claim 8 (depends on 1) The method of claim 1, further comprising: obtaining a mapping between RACH occasions (ROs) and SSBs, a first portion of the SSBs corresponding to the first SSB type and a second portion of the SSBs corresponding to the second SSB type. ### Claim 9 (depends on 1) The method of claim 1, further comprising: obtaining a mapping between RACH occasions (ROs) and first SSBs, the first SSBs corresponding to the first SSB type, the mapping indicating spatial filtering configurations suitable for transmissions or reflections at the RIS. ### Claim 10 (depends on 1) The method of claim 1, wherein a received second SSB type is prioritized over a received first SSB type in determining whether the RIS-assisted procedures are needed. ### Claim 11 An apparatus for wireless communication to be performed by a user equipment (UE), comprising: memory; and a processor communicatively coupled with the memory and configured to: receive, from a base station, a synchronization signal block (SSB) via a reconfigurable intelligent surface (RIS), the SSB corresponding to a first SSB type configured for RIS-assisted procedures or corresponding to a second SSB type configured for non-RIS-assisted procedures; determine, based on the SSB, whether the RIS-assisted procedures are needed; and transmit, to the base station according to the SSB, an indication whether the SSB corresponds to the first SSB type as part of a random access channel (RACH) procedure, wherein the first SSB type indicates that the RIS-assisted procedures are needed. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein: to receive the SSB corresponding to the first SSB type configured for the RIS-assisted procedures comprises to receive the SSB reflected by the RIS on a receive spatial filter of the UE, the SSB having been transmitted at multiple SSB resources using a same transmit spatial filter of the base station; and wherein the processor is further configured to transmit, to the base station, a physical random access channel (PRACH) on a transmit spatial filter of the UE, wherein the transmit spatial filter of the UE corresponds to the receive spatial filter of the UE that received the SSB. ### Claim 13 (depends on 11) The apparatus of claim 11, wherein the processor is further configured to: obtain a mapping between RACH occasions (ROs) and SSB types; select a RO according to the SSB and the mapping, the RO indicating that the SSB corresponds to the first SSB type; and transmit, to the base station, a physical random access channel (PRACH) using the RO. ### Claim 14 (depends on 11) The apparatus of claim 11, wherein the processor is further configured to: obtain a set of physical random access channel (PRACH) preambles; select a PRACH preamble from the set of PRACH preambles, the selected PRACH preamble indicating that the SSB corresponds to the first SSB type; and transmit, to the base station, a PRACH comprising the selected PRACH preamble. ### Claim 15 (depends on 11) The apparatus of claim 11, wherein the processor is further configured to: transmit, to the base station, a physical uplink shared channel (PUSCH) carrying the indication that the SSB corresponds to the first SSB type, wherein: a demodulation reference signal of the PUSCH indicates that the SSB corresponds to the first SSB type; or a scrambling code of the PUSCH indicates that the SSB corresponds to the first SSB type; or a payload of the PUSCH comprises the indication that the SSB corresponds to the first SSB type. ### Claim 16 (depends on 11) The apparatus of claim 11, wherein the processor is further configured to: select a physical uplink shared channel (PUSCH) occasion indicating that the SSB corresponds to the first SSB type; and transmit, to the base station, a PUSCH on the PUSCH occasion. ### Claim 17 (depends on 11) The apparatus of claim 11, wherein the processor is further configured to: obtain a first mapping between first RACH occasions (ROs) and first SSBs, the first SSBs corresponding to the first SSB type; and obtain a second mapping between second ROs and second SSBs, the second SSBs corresponding to the second SSB type. ### Claim 18 (depends on 11) The apparatus of claim 11, wherein the processor is further configured to: obtain a mapping between RACH occasions (ROs) and SSBs, a first portion of the SSBs corresponding to the first SSB type and a second portion of the SSBs corresponding to the second SSB type. ### Claim 19 (depends on 11) The apparatus of claim 11, wherein the processor is further configured to: obtain a mapping between RACH occasions (ROs) and first SSBs, the first SSBs corresponding to the first SSB type, the mapping indicating spatial filtering configurations suitable for transmissions or reflections at the RIS. ### Claim 20 An apparatus for wireless communication to be performed by a user equipment (UE), comprising: means for receiving, from a base station, a synchronization signal block (SSB) via a reconfigurable intelligent surface (RIS), the SSB corresponding to a first SSB type configured for RIS-assisted procedures or corresponding to a second SSB type configured for non-RIS-assisted procedures; means for determining, based on the SSB, whether the RIS-assisted procedures are needed; and means for transmitting, to the base station according to the SSB, an indication whether the SSB corresponds to the first SSB type as part of a random access channel (RACH) procedure, wherein the first SSB type indicates that the RIS-assisted procedures are needed. ### Claim 21 (depends on 20) The apparatus of claim 20, wherein: the means for receiving the SSB corresponding to the first SSB type configured for the RIS-assisted procedures comprise further means for receiving the SSB reflected by the RIS on a receive spatial filter of the UE, the SSB having been transmitted at multiple SSB resources using a same transmit spatial filter of the base station; and the apparatus further comprises means for transmitting, to the base station, a physical random access channel (PRACH) on a transmit spatial filter of the UE, wherein the transmit spatial filter of the UE corresponds to the receive spatial filter of the UE that received the SSB. ### Claim 22 (depends on 20) The apparatus of claim 20, further comprising: means for obtaining a mapping between RACH occasions (ROs) and SSB types; means for selecting a RO according to the SSB and the mapping, the RO indicating that the SSB corresponds to the first SSB type; and means for transmitting, to the base station, a physical random access channel (PRACH) using the RO. ### Claim 23 (depends on 20) The apparatus of claim 20, further comprising: means for obtaining a set of physical random access channel (PRACH) preambles; means for selecting a PRACH preamble from the set of PRACH preambles, the selected PRACH preamble indicating that the SSB corresponds to the first SSB type; and means for transmitting, to the base station, a PRACH comprising the selected PRACH preamble. ### Claim 24 (depends on 20) The apparatus of claim 20, further comprising: means for transmitting, to the base station, a physical uplink shared channel (PUSCH) carrying the indication that the SSB corresponds to the first SSB type, wherein: a demodulation reference signal of the PUSCH indicates that the SSB corresponds to the first SSB type; or a scrambling code of the PUSCH indicates that the SSB corresponds to the first SSB type; or a payload of the PUSCH comprises the indication that the SSB corresponds to the first SSB type. ### Claim 25 (depends on 20) The apparatus of claim 20, further comprising: means for selecting a physical uplink shared channel (PUSCH) occasion indicating that the SSB corresponds to the first SSB type; and means for transmitting, to the base station, a PUSCH on the PUSCH occasion. ### Claim 26 (depends on 20) The apparatus of claim 20, further comprising: means for obtaining a first mapping between first RACH occasions (ROs) and first SSBs, the first SSBs corresponding to the first SSB type; and means for obtaining a second mapping between second ROs and second SSBs, the second SSBs corresponding to the second SSB type. ### Claim 27 (depends on 20) The apparatus of claim 20, further comprising: means for obtaining a mapping between RACH occasions (ROs) and SSBs, a first portion of the SSBs corresponding to the first SSB type and a second portion of the SSBs corresponding to the second SSB type. ### Claim 28 (depends on 20) The apparatus of claim 20, further comprising: means for obtaining a mapping between RACH occasions (ROs) and first SSBs, the first SSBs corresponding to the first SSB type, the mapping indicating spatial filtering configurations suitable for transmissions or reflections at the RIS.