# US 2020/0404642 A1 · Method and device for selecting beam > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0404642 A1 - Document ID: US20200404642A1 - Status: Published application - Kind: A1 - Application number: 17/011,454 - Filed: 2020-09-03 - Published: 2020-12-24 - Earliest claimed: 2018-03-30 - Assignees: Beijing Xiaomi Mobile Software Co., Ltd. - Applicants: Beijing Xiaomi Mobile Software Co., Ltd. - Inventors: Yajun ZHU - Web page: https://patentgrep.com/patent/US20200404642A1 ## CPC - H04W 72/046: {the resource being in the space domain, e.g. beams} - H04L 5/0023: {Time-frequency-space} - H04W 24/02: Arrangements for optimising operational condition - H04W 56/001: {Synchronization between nodes} - H04W 72/542: using measured or perceived quality - H04W 74/0833: Random access procedures, e.g. with 4-step access - H04W 84/042: {Public Land Mobile systems, e.g. cellular systems} - 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 selecting a beam includes: receiving positions for monitoring data to be transmitted within a set transmission period are determined. Data to be transmitted sent by a data sending terminal using different beams are monitored at the receiving positions. The data to be transmitted can indicate a transmission beam corresponding to the data. An optimal transmission beam can be determined based on monitoring results. ## Claims ### Claim 1 A method for selecting a beam, applied to a data receiving terminal, and comprising: determining receiving positions for monitoring data to be transmitted within a set transmission period; monitoring, at the receiving positions, data to be transmitted sent by a data sending terminal using different beams, wherein the data to be transmitted is able to indicate a transmission beam corresponding to the data; and determining an optimal transmission beam based on monitoring results. ### Claim 2 (depends on 1) The method of claim 1, wherein the determining the receiving positions for monitoring the data to be transmitted within the set transmission period comprises: receiving a position parameter sent by a base station through radio resource control (RRC) signaling, a media access control (MAC) control element (CE) or physical layer signaling; and determining receiving positions based on the position parameter, or determining a receiving window containing a plurality of receiving positions based on the position parameter. ### Claim 3 (depends on 1) The method of claim 1, wherein the determining the receiving positions for monitoring the data to be transmitted within the set transmission period comprises: determining a position parameter for monitoring the data to be transmitted within the set transmission period based on system agreement; and determining receiving positions based on the position parameter, or determining a receiving window containing a plurality of receiving positions based on the position parameter. ### Claim 4 (depends on 1) The method of claim 1, wherein in response to that the data receiving terminal is a user equipment, the data to be transmitted is a synchronous block signal; or, the data to be transmitted is a synchronous block signal, beam indication signaling or a beam indication signal. ### Claim 5 (depends on 4) The method of claim 4, wherein the beam indication signal is a pre-defined pilot sequence, and the beam indication signaling or the beam indication signal carries beam information of a data transmission beam. ### Claim 6 (depends on 1) The method of claim 1, wherein in response to that the data receiving terminal is a base station, the data to be transmitted is a random access preamble. ### Claim 7 (depends on 1) The method of claim 1, wherein the determining the optimal transmission beam based on the monitoring results comprising. determining a data transmission beam corresponding to data to be transmitted with a highest receiving quality as the optimal transmission beam. ### Claim 8 A method for selecting a beam, applied to a data sending terminal, and comprising: determining a target sending position for each beam based on a channel state of a channel to be detected and a set position parameter within a set transmission period; and sending, by a corresponding transmission beam, data to be transmitted at the target sending position for each beam, wherein a data receiving terminal determines an optimal beam based on monitoring results of monitoring the data to be transmitted. ### Claim 9 (depends on 8) The method of claim 8, wherein the determining the target sending position for each beam based on the channel state of the channel to be detected and the set position parameter within the set transmission period comprises: determining, based on the set position parameter, sending positions or a sending window which is able to be used to send the data to be transmitted for each beam; determining, among the sending positions which are able to be used to send the data to be transmitted for each beam, a first sending position or all of the sending positions at which a channel is in an unoccupied state as the target sending position for each beam; or determining, in the sending window which is able to be used to send the data to be transmitted, a first position or all of the positions at which a channel is in an unoccupied state as the target sending position for each beam. ### Claim 10 (depends on 8) The method of claim 8, wherein the set position parameter is obtained by system agreement or the set position parameter is set by a base station. ### Claim 11 (depends on 8) The method of claim 8, wherein in response to that the data sending terminal is a base station, the sending by the corresponding transmission beam the data to be transmitted at the target sending position for each beam comprises: sending, by a corresponding transmission beam, the synchronous block signal at the first position for sending a synchronous block signal in the target sending positions; in response to that the synchronous block signal is not successfully sent, sending, by corresponding transmission beams, beam indication signaling or a beam indication signal, or a synchronous block signal at the other target sending positions; and in response to that the synchronous block signal is successfully sent, continuing sending beam indication signaling, a beam indication signal or a synchronous block signal at other subsequent target sending positions, or prohibiting from sending beam indication signaling, a beam indication signal or a synchronous block signal at other subsequent target sending positions. ### Claim 12 (depends on 11) The method of claim 11, wherein the beam indication signal is a pre-defined pilot sequence, and the beam indication signaling or the beam indication signal carries beam information of a data transmission beam. ### Claim 13 (depends on 8) The method of claim 8, wherein in response to that the data sending terminal is user equipment, the method further comprises: receiving the set position parameter sent by a base station through radio resource control (RRC) signaling, a media access control (MAC) control element (CE) or physical layer signaling. ### Claim 14 (depends on 13) The method of claim 13, wherein the sending by the corresponding transmission beam the data to be transmitted at the target sending position for each beam comprises: sending a random access preamble by a corresponding transmission beam at the target sending position for each beam. ### Claim 15 A device for selecting a beam, applied to a data receiving terminal, and comprising: a processor; memory for storing processor-executable instructions; wherein the processor is configured to: determine receiving positions for monitoring data to be transmitted within a set transmission period; monitor, at the receiving positions, the data to be transmitted sent by a data sending terminal using different beams, wherein the data to be transmitted is able to indicate a transmission beam corresponding to the data; and determine an optimal transmission beam based on monitoring results. ### Claim 16 (depends on 15) The device of claim 15, wherein the processor is further configured to: receive a position parameter sent by a base station through radio resource control (RRC) signaling, a media access control (MAC) control element (CE) or physical layer signaling; and determine receiving positions based on the position parameter, or determine a receiving window containing a plurality of receiving positions based on the position parameter. ### Claim 17 (depends on 15) The device of claim 15, wherein the processor is further configured to: determine a position parameter for monitoring the data to be transmitted within the set transmission period based on system agreement; and determine receiving positions based on the position parameter, or determine a receiving window containing a plurality of receiving positions based on the position parameter. ### Claim 18 (depends on 15) The device of claim 15, wherein, in response to that the data receiving terminal is a user equipment, the data to be transmitted is a synchronous block signal; or, the data to be transmitted is a synchronous block signal, beam indication signaling or a beam indication signal. ### Claim 19 (depends on 18) The device of claim 18, wherein the beam indication signal is a pre-defined pilot sequence, and the beam indication signaling or the beam indication signal carries beam information of a data transmission beam. ### Claim 20 (depends on 1) A communication system implementing the method of claim 1, comprising the data receiving terminal and the data sending terminal, which include a base station and user equipment (UE), wherein the data receiving terminal is configured to: monitor the synchronous block signal or other signaling or signal that indicate a transmission beam in at least two receiving positions within a synchronous block signal transmission period; and determine an optimal transmission beam based on monitoring results; thereby enabling the data receiving terminal to monitor the data to be transmitted in more than two receiving positions during an initial access process of the UE when communication channels are busy, and to determine the optimal transmission beam for communication.