# US 2019/0319833 A1 · Beam failure recovery in connection with switching bwp > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2019/0319833 A1 - Document ID: US20190319833A1 - Status: Published application - Kind: A1 - Application number: 16/297,546 - Filed: 2019-03-08 - Published: 2019-10-17 - Earliest claimed: 2018-04-14 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Sumeeth NAGARAJA; Yan ZHOU; Tao LUO; Alexandros MANOLAKOS; Juan MONTOJO - Web page: https://patentgrep.com/patent/US20190319833A1 ## CPC - H04L 41/0668: by dynamic selection of recovery network elements, e.g. replacement by the most appropriate element after failure - H04W 36/0079: {in case of hand-off failure or rejection} - H04B 7/06964: {Re-selection of one or more beams after beam failure} - H04L 5/001: {the frequencies being arranged in component carriers} - H04L 5/0051: {of dedicated pilots, i.e. pilots destined for a single user or terminal} - H04L 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals} - H04L 41/0677: Localisation of faults - H04L 43/0823: Errors, e.g. transmission errors - H04W 24/10: Scheduling measurement reports {; Arrangements for measurement reports} - H04W 28/20: Negotiating bandwidth - H04W 36/0085: {Hand-off measurements} - H04W 72/046: {the resource being in the space domain, e.g. beams} - H04W 72/542: using measured or perceived quality - H04L 43/16: Threshold monitoring - H04W 74/0833: Random access procedures, e.g. with 4-step access - H04W 74/0838: using contention-free random access [CFRA] - 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) - H04B: TRANSMISSION ## Abstract A method, a computer-readable medium, and an apparatus are provided for wireless communication at a UE. The apparatus switches from a first, active BWP to a second, active BWP. Then, the apparatus measures a first radio link quality of a configured CORESET TCI or a beam failure detection RS upon switching to the second, active BWP. For example, the apparatus may switch the active BWP based on detecting an expiration of a BWP inactivity timer. The apparatus may then determine based on a threshold radio link quality whether to perform a measurement of a second radio link quality of a beam failure recovery candidate resource set or to continue to monitor the configured CORESET TCI in the second, active BWP. ## Claims ### Claim 1 A method of wireless communication at a User Equipment (UE), the method comprising: switching from a first, active Bandwidth Part (BWP) to a second, active BWP; measuring a first radio link quality of a configured Control-resource set (CORESET) Transmission Configuration Indicator (TCI) or a beam failure detection Reference Signal (RS) upon switching to the second, active BWP; and determining based on a threshold radio link quality whether to perform a measurement of a second radio link quality of a beam failure recovery candidate resource set or to continue to monitor the configured CORESET TCI in the second, active BWP. ### Claim 2 (depends on 1) The method of claim 1, further comprising: detecting an expiration of a BWP inactivity timer, wherein the UE switches from the first, active BWP to the second, active BWP in response to the detecting the expiration of the BWP inactivity timer. ### Claim 3 (depends on 1) The method of claim 1, wherein the UE continues to monitor the configured CORESET TCI in the second, active BWP when the first radio link quality of the configured CORESET TCI or the beam failure detection RS meets the threshold radio link quality. ### Claim 4 (depends on 1) The method of claim 1, wherein the UE performs the measurement of the second radio link quality of the beam failure recovery candidate resource set when the first radio link quality of the configured CORESET TCI or the beam failure detection RS does not meet the threshold radio link quality. ### Claim 5 (depends on 4) The method of claim 4, wherein the UE determines whether to perform a contention free random access procedure on a candidate beam or a contention based random access procedure on the candidate beam based on whether the measurement of the second radio link quality of the beam failure recovery candidate resource set meets a second threshold. ### Claim 6 (depends on 5) The method of claim 5, wherein the second threshold is configured by a network. ### Claim 7 (depends on 5) The method of claim 5, wherein the UE performs the contention free random access procedure on the candidate beam when the second radio link quality meets the second threshold. ### Claim 8 (depends on 5) The method of claim 5, wherein the UE performs the contention based random access procedure on the candidate beam when the second radio link quality does not meet the second threshold. ### Claim 9 (depends on 1) The method of claim 1, further comprising: receiving a configuration of at least one value for transmission of a beam failure recovery signal or for transmission of another signal indicating a change of a preferred link to a base station. ### Claim 10 (depends on 1) The method of claim 1, further comprising: changing at least one of a timer or a number of requests in a beam failure detection based on the switching to the second, active BWP. ### Claim 11 (depends on 10) The method of claim 10, wherein the changing the at least one of the timer or the number of requests comprises reducing or disabling metrics relating to the at least one of the timer or the number of requests. ### Claim 12 An apparatus for wireless communication at a User Equipment (UE), comprising: means for switching from a first, active Bandwidth Part (BWP) to a second, active BWP; means for measuring a first radio link quality of a configured Control-resource set (CORESET) Transmission Configuration Indicator (TCI) or a beam failure detection Reference Signal (RS) upon switching to the second, active BWP; and means for determining based on a threshold radio link quality whether to perform a measurement of a second radio link quality of a beam failure recovery candidate resource set or to continue to monitor the configured CORESET TCI in the second, active BWP. ### Claim 13 (depends on 12) The apparatus of claim 12, further comprising: means for detecting an expiration of a BWP inactivity timer, wherein the UE switches from the first, active BWP to the second, active BWP in response to the detecting the expiration of the BWP inactivity timer. ### Claim 14 (depends on 12) The apparatus of claim 12, wherein the means for measuring further perform the measurement of the second radio link quality of the beam failure recovery candidate resource set when the first radio link quality of the configured CORESET TCI or the beam failure detection RS does not meet the threshold radio link quality, the apparatus further comprising: means for determining whether to perform a contention free random access procedure on a candidate beam or a contention based random access procedure on the candidate beam based on whether the measurement of the second radio link quality of the beam failure recovery candidate resource set meets a second threshold; means for performing the contention free random access procedure on the candidate beam when the second radio link quality meets the second threshold; and means for performing the contention based random access procedure on the candidate beam when the second radio link quality does not meet the second threshold. ### Claim 15 (depends on 12) The apparatus of claim 12, further comprising: means for receiving a configuration of at least one value for transmission of a beam failure recovery signal. ### Claim 16 (depends on 12) The apparatus of claim 12, further comprising: means for reducing at least one of a timer or a number of requests in a beam failure detection based on the switching to the second, active BWP. ### Claim 17 An apparatus for wireless communication at a User Equipment (UE), comprising: a memory; and at least one processor coupled to the memory and configured to: switch from a first, active Bandwidth Part (BWP) to a second, active BWP; measure a first radio link quality of a configured Control-resource set (CORESET) Transmission Configuration Indicator (TCI) or a beam failure detection Reference Signal (RS) upon switching to the second, active BWP; and determine based on a threshold radio link quality whether to perform a measurement of a second radio link quality of a beam failure recovery candidate resource set or to continue to monitor the configured CORESET TCI in the second, active BWP. ### Claim 18 (depends on 17) The apparatus of claim 17, wherein the at least one processor is further configured to: detect an expiration of a BWP inactivity timer, wherein the UE switches from the first, active BWP to the second, active BWP in response to the detecting the expiration of the BWP inactivity timer. ### Claim 19 (depends on 17) The apparatus of claim 17, wherein the UE continues to monitor the configured CORESET TCI in the second, active BWP when the first radio link quality of the configured CORESET TCI or the beam failure detection RS meets the threshold radio link quality. ### Claim 20 (depends on 17) The apparatus of claim 17, wherein the UE performs the measurement of the second radio link quality of the beam failure recovery candidate resource set when the first radio link quality of the configured CORESET TCI or the beam failure detection RS does not meet the threshold radio link quality. ### Claim 21 (depends on 20) The apparatus of claim 20, wherein the UE determines whether to perform a contention free random access procedure on a candidate beam or a contention based random access procedure on the candidate beam based on whether the measurement of the second radio link quality of the beam failure recovery candidate resource set meets a second threshold. ### Claim 22 (depends on 21) The apparatus of claim 21, wherein the at least one processor is further configured to: perform the contention free random access procedure on the candidate beam when the second radio link quality meets the second threshold. ### Claim 23 (depends on 21) The apparatus of claim 21, wherein the at least one processor is further configured to: perform the contention based random access procedure on the candidate beam when the second radio link quality does not meet the second threshold. ### Claim 24 (depends on 17) The apparatus of claim 17, wherein the at least one processor is further configured to: receive a configuration of at least one value for transmission of a beam failure recovery signal or for transmission of another signal indicating a change of a preferred link to a base station. ### Claim 25 (depends on 17) The apparatus of claim 17, wherein the at least one processor is further configured to: change at least one of a timer or a number of requests in a beam failure detection based on the switching to the second, active BWP. ### Claim 26 (depends on 25) The apparatus of claim 25, wherein the changing the at least one of the timer or the number of requests comprises reducing or disabling metrics relating to the at least one of the timer or the number of requests. ### Claim 27 A computer-readable medium storing computer executable code for wireless communication at a User Equipment (UE), comprising code to: switch from a first, active Bandwidth Part (BWP) to a second, active BWP; measure a first radio link quality of a configured Control-resource set (CORESET) Transmission Configuration Indicator (TCI) or a beam failure detection Reference Signal (RS) upon switching to the second, active BWP; and determine based on a threshold radio link quality whether to perform a measurement of a second radio link quality of a beam failure recovery candidate resource set or to continue to monitor the configured CORESET TCI in the second, active BWP. ### Claim 28 (depends on 27) The computer-readable medium of claim 27, further comprising code to: detect an expiration of a BWP inactivity timer, wherein the UE switches from the first, active BWP to the second, active BWP in response to the detecting the expiration of the BWP inactivity timer. ### Claim 29 (depends on 27) The computer-readable medium of claim 27, further comprising code to: perform the measurement of the second radio link quality of the beam failure recovery candidate resource set when the first radio link quality of the configured CORESET TCI or the beam failure detection RS does not meet the threshold radio link quality; and perform a contention free random access procedure on a candidate beam or a contention based random access procedure on the candidate beam based on whether the measurement of the second radio link quality of the beam failure recovery candidate resource set meets a second threshold. ### Claim 30 (depends on 29) The computer-readable medium of claim 29, further comprising code to: perform the contention free random access procedure on the candidate beam when the second radio link quality meets the second threshold; and perform the contention based random access procedure on the candidate beam when the second radio link quality does not meet the second threshold.