# US 2021/0345340 A1 · Method to mitigate timing resolution limitation due to ssb with smaller scs > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0345340 A1 - Document ID: US20210345340A1 - Status: Published application - Kind: A1 - Application number: 17/230,713 - Filed: 2021-04-14 - Published: 2021-11-04 - Earliest claimed: 2020-05-01 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Jun MA; Xiaoxia ZHANG; Qiang WU; Iyab Issam SAKHNINI; Jing SUN; Mehmet Izzet GURELLI; Ahmed Abdelaziz Ibrahim Abdelaziz ZEWAIL - Web page: https://patentgrep.com/patent/US20210345340A1 ## CPC - H04L 5/0091: {Signalling for the administration of the divided path, e.g. signalling of configuration information} - H04W 72/53: based on regulatory allocation policies - H04L 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals} - H04L 27/26025: {Numerology, i.e. varying one or more of symbol duration, subcarrier spacing, Fourier transform size, sampling rate or down-clocking (allocating sub-channels of the transmission path H04L5/003)} - H04L 27/2607: {Cyclic extensions} - H04L 27/2662: {Symbol synchronisation} - H04L 27/2675: {Pilot or known symbols} - H04W 56/001: {Synchronization between nodes} - H04W 72/0446: Resources in time domain, e.g. slots or frames - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - 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 relate to wireless communications, and more particularly, to techniques for mitigating timing resolution limitations due to synchronization signal blocks (SSBs) with low subcarrier spacing (SCS). An example method by a user equipment (UE) generally includes detecting a SSB; determining a start time of a control resource set (CORESET) associated with the detected SSB, wherein the start time of the CORESET is aligned with a boundary of a symbol having a larger cyclic prefix (CP) than one or more other symbols in a same half-subframe; and monitoring the CORESET for a physical downlink control channel (PDCCH) transmission. ## Claims ### Claim 1 A method for wireless communication by a user-equipment (UE), comprising: detecting a synchronization signal block (SSB); determining a start time of a control resource set (CORESET) associated with the detected SSB, wherein the start time of the CORESET is aligned with a boundary of a symbol having a larger cyclic prefix (CP) than one or more other symbols in a same half-subframe; and monitoring the CORESET for a physical downlink control channel (PDCCH) transmission. ### Claim 2 (depends on 1) The method of claim 1, further comprising refining a symbol timing estimate based on a demodulation reference signal (DMRS) transmitted with the PDCCH. ### Claim 3 (depends on 1) The method of claim 1, wherein: the SSB has a first subcarrier spacing (SCS); and the CORESET has a second SCS. ### Claim 4 (depends on 3) The method of claim 3, wherein a size of the larger CP is determined based, at least in part, on the SCS of the CORESET. ### Claim 5 (depends on 1) The method of claim 1, wherein the start time of the CORESET is aligned with a beginning of a half-subframe boundary. ### Claim 6 (depends on 1) The method of claim 1, wherein symbols having larger CPs are distributed among a time window that spans a number of symbols and occurs with a periodicity. ### Claim 7 (depends on 6) The method of claim 6, wherein the periodicity of the CORESET associated with the detected SSB relates to the periodicity of the time window and number of beams used to transmit SSBs. ### Claim 8 (depends on 6) The method of claim 6, wherein a start time of the CORESET is aligned with a symbol other than a symbol at a beginning of a half-subframe boundary. ### Claim 9 A method for wireless communication by a network entity, comprising: transmitting one or more synchronization signal blocks (SSBs); determining one or more start times for one or more control resource sets (CORESETs) associated with the one or more SSBs, wherein the one or more start times of the one or more CORESETs are aligned with boundaries of orthogonal frequency division multiplexed (OFDM) symbols having larger cyclic prefixes (CPs) than one or more other OFDM symbols in a same half-subframe; and transmitting a physical downlink control channel (PDCCH) in one or more of the one or more CORESETs. ### Claim 10 (depends on 9) The method of claim 9, wherein: the one or more SSBs have a first subcarrier spacing (SCS); and the one or more CORESETs have a second SCS. ### Claim 11 (depends on 10) The method of claim 10, wherein a size of the larger CP is determined based, at least in part, on the SCS of the one or more CORESETs. ### Claim 12 (depends on 9) The method of claim 9, wherein a start time of the one or more CORESETs is aligned with a beginning of a half-subframe boundary. ### Claim 13 (depends on 9) The method of claim 9, wherein symbols having larger CPs are distributed among a time window that spans a number of symbols and occurs with a periodicity. ### Claim 14 (depends on 13) The method of claim 13, wherein the periodicity of the one or more CORESETs associated with the one or more SSBs relates to the periodicity of the time window and number of beams used to transmit one or more SSBs. ### Claim 15 (depends on 13) The method of claim 13, wherein a start time of the one or more CORESETs is aligned with a symbol other than a symbol at a beginning of a half-subframe boundary. ### Claim 16 An apparatus for wireless communication by a user-equipment (UE), comprising: at least one processor and a memory configured to detect a synchronization signal block (SSB); determine a start time of a control resource set (CORESET) associated with the detected SSB, wherein the start time of the CORESET is aligned with a boundary of a symbol having a larger cyclic prefix (CP) than one or more other symbols in a same half-subframe; and monitor the CORESET for a physical downlink control channel (PDCCH) transmission. ### Claim 17 (depends on 16) The apparatus of claim 16, wherein the at least one processor and the memory are further configured to refine a symbol timing estimate based on a demodulation reference signal (DMRS) transmitted with the PDCCH. ### Claim 18 (depends on 16) The apparatus of claim 16, wherein: the SSB has a first subcarrier spacing (SCS); and the CORESET has a second SCS. ### Claim 19 (depends on 18) The apparatus of claim 18, wherein a size of the larger CP is determined based, at least in part, on the SCS of the CORESET. ### Claim 20 (depends on 16) The apparatus of claim 16, wherein the start time of the CORESET is aligned with a beginning of a half-subframe boundary. ### Claim 21 (depends on 16) The apparatus of claim 16, wherein symbols having larger CPs are distributed among a time window that spans a number of symbols and occurs with a periodicity. ### Claim 22 (depends on 21) The apparatus of claim 21, wherein the periodicity of the CORESET associated with the detected SSB relates to the periodicity of the time window and number of beams used to transmit SSBs. ### Claim 23 (depends on 21) The apparatus of claim 21, wherein a start time of the CORESET is aligned with a symbol other than a symbol at a beginning of a half-subframe boundary. ### Claim 24 An apparatus for wireless communication by a network entity, comprising: at least one processor and a memory configured to transmit one or more synchronization signal blocks (SSBs); determine start times for one or more control resource sets (CORESETs) associated with the one or more SSBs, wherein the one or more start times of the one or more CORESETs are aligned with boundaries of orthogonal frequency division multiplexed (OFDM) symbols having larger cyclic prefixes (CPs) than one or more other OFDM symbols in a same half-subframe; and transmit a physical downlink control channel (PDCCH) in one or more of the one or more CORESETs. ### Claim 25 (depends on 24) The apparatus of claim 24, wherein: the one or more SSBs have a first subcarrier spacing (SCS); and the one or more CORESETs have a second SCS. ### Claim 26 (depends on 25) The apparatus of claim 25, wherein a size of the larger CP is determined based, at least in part, on the SCS of the one or more CORESETs. ### Claim 27 (depends on 24) The apparatus of claim 24, wherein a start time of the one or more CORESETs is aligned with a beginning of a half-subframe boundary. ### Claim 28 (depends on 24) The apparatus of claim 24, wherein symbols having larger CPs are distributed among a time window that spans a number of symbols and occurs with a periodicity. ### Claim 29 (depends on 28) The apparatus of claim 28, wherein the periodicity of the one or more CORESETs associated with the one or more SSBs relates to the periodicity of the time window and number of beams used to transmit one or more SSBs. ### Claim 30 (depends on 28) The apparatus of claim 28, wherein a start time of the one or more CORESETs is aligned with a symbol other than a symbol at a beginning of a half-subframe boundary.