# US 11,451,976 B2 · Method and apparatus for performing UE beamforming in a wireless communication system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,451,976 B2 - Document ID: US11451976B2 - Status: Granted - Kind: B2 - Application number: 17/074,943 - Filed: 2020-10-20 - Published: 2021-02-04 - Granted: 2022-09-20 - Earliest claimed: 2016-06-24 - Assignees: ASUSTeK COMPUTER INC. - Applicants: ASUSTek Computer Inc. - Inventors: Yu-Hsuan Guo; Meng-Hui Ou - Web page: https://patentgrep.com/patent/US11451976B2 ## CPC - H04B 7/0404: the mobile station comprising multiple antennas, e.g. to provide uplink diversity - H04W 16/28: using beam steering - H04B 7/06964: {Re-selection of one or more beams after beam failure} - H04B 7/088: {using beam selection} - H04L 5/0023: {Time-frequency-space} - H04L 5/0051: {of dedicated pilots, i.e. pilots destined for a single user or terminal} - H04W 56/001: {Synchronization between nodes} - H04W 72/046: {the resource being in the space domain, e.g. beams} - H04W 72/23: in the downlink direction of a wireless link, i.e. towards a terminal - H04W 76/18: Management of setup rejection or failure - H04W 76/19: Connection re-establishment - H04B 7/0408: using two or more beams, i.e. beam diversity - H04L 5/0048: {Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091)} - H04L 5/0053: {Allocation of signalling, i.e. of overhead other than pilot signals} - H04B: TRANSMISSION - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A method for a wireless communications system is disclosed. In one example, a user equipment (UE) (e.g. a mobile phone), receives an indication from a network about one or more UE beams that the UE can use for transmission or reception. The UE uses the one or more UE beams for transmission or reception. If and when a certain condition is fulfilled, for example, there is a beam tracking failure, the UE transmits or receives a specific signal via a specific UE beam. The specific UE beam is different from the one or more UE beams that were indicated by the network, and is selected by the UE. ## Claims ### Claim 1 A method for a user equipment (UE), comprising: receiving a first indication from a network node about at least one UE beam to be used for a transmission or a reception in a physical downlink control channel (PDCCH); receiving a periodic signaling from the network node associated with detection of a change of a serving beam for beam tracking; using the at least one UE beam for the transmission or the reception at a first time; and responsive to the UE detecting failure of the beam tracking based on the periodic signaling at a second time: selecting, by the UE, a second UE beam, wherein the second UE beam is different than the at least one UE beam; and transmitting a second indication about the change of the serving beam using the second UE beam, wherein the transmitting the second indication using the second UE beam responsive to the UE detecting failure of the beam tracking based on the periodic signaling at the second time is performed without UE beam sweeping. ### Claim 2 (depends on 1) The method of claim 1, wherein the transmitting the second indication is performed responsive to (i) the UE detecting failure of the beam tracking based on the periodic signaling at the second time is performed and (ii) determining that the at least one UE beam and the serving beam are misaligned. ### Claim 3 (depends on 1) The method of claim 1, wherein the beam tracking is used to track and change the serving beam. ### Claim 4 (depends on 1) The method of claim 1, wherein the UE maintains information about the at least one UE beam to be used for the transmission or the reception based on the beam tracking. ### Claim 5 (depends on 1) The method of claim 1, wherein the UE receives the first indication together with scheduling information for the transmission or the reception. ### Claim 6 (depends on 1) The method of claim 1, wherein timing associated with transmitting the second indication is configured by the network node. ### Claim 7 (depends on 1) The method of claim 1, wherein the first indication implicitly indicates that the at least one UE beam to be used for the transmission or the reception is the at least one UE beam receiving scheduling information for the transmission or the reception. ### Claim 8 (depends on 1) The method of claim 1, wherein the selecting the second UE beam responsive to the UE detecting failure of the beam tracking based on the periodic signaling at the second time is performed responsive to successfully receiving a common signal from the second UE beam. ### Claim 9 (depends on 8) The method of claim 8, wherein the common signal includes a synchronization signal or a reference signal. ### Claim 10 A user equipment (UE), comprising: a control circuit; a processor installed in the control circuit; and a memory installed in the control circuit and operatively coupled to the processor, wherein the processor is configured to execute a program code stored in the memory to perform operations comprising: receiving a first indication from a network node about at least one UE beam to be used for a transmission or a reception in a physical downlink control channel (PDCCH); receiving a periodic signaling from the network node associated with detection of a change of a serving beam for beam tracking; using the at least one UE beam for the transmission or the reception at a first time; and responsive to the UE detecting failure of the beam tracking based on the periodic signaling at a second time: selecting, by the UE, a second UE beam, wherein the second UE beam is different than the at least one UE beam; and transmitting a second indication about the change of the serving beam using the second UE beam, wherein the transmitting the second indication using the second UE beam responsive to the UE detecting failure of the beam tracking based on the periodic signaling at the second time is performed without UE beam sweeping. ### Claim 11 (depends on 10) The UE claim 10, wherein the transmitting the second indication is performed responsive to (i) the UE detecting failure of the beam tracking based on the periodic signaling at the second time is performed and (ii) determining that the at least one UE beam and the serving beam are misaligned. ### Claim 12 (depends on 10) The UE of claim 10, wherein the beam tracking is used to track and change the serving beam. ### Claim 13 (depends on 10) The UE of claim 10, wherein the UE maintains information about the at least one UE beam to be used for the transmission or the reception based on the beam tracking. ### Claim 14 (depends on 10) The UE of claim 10, wherein the UE receives the first indication together with scheduling information for the transmission or the reception. ### Claim 15 (depends on 10) The UE of claim 10, wherein timing associated with transmitting the second indication is configured by the network node. ### Claim 16 (depends on 10) The UE of claim 10, wherein the first indication implicitly indicates that the at least one UE beam to be used for the transmission or the reception is the at least one UE beam receiving scheduling information for the transmission or the reception. ### Claim 17 (depends on 10) The UE of claim 10, wherein the selecting the second UE beam responsive to the UE detecting failure of the beam tracking based on the periodic signaling at the second time is performed responsive to successfully receiving a common signal from the second UE beam. ### Claim 18 (depends on 17) The UE of claim 17, wherein the common signal includes a synchronization signal or a reference signal.