# US 10,873,380 B2 · Adaptive beam selection 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 10,873,380 B2 - Document ID: US10873380B2 - Status: Granted - Kind: B2 - Application number: 16/075,713 - Filed: 2017-02-15 - Published: 2019-02-14 - Granted: 2020-12-22 - Earliest claimed: 2016-02-15 - Assignees: Telefonaktiebolaget LM Ericsson (publ) - Applicants: Telefonaktiebolaget LM Ericsson (publ) - Inventors: Ali Nader; Béla Rathonyi - Web page: https://patentgrep.com/patent/US10873380B2 ## CPC - H04W 72/046: {the resource being in the space domain, e.g. beams} - H04B 7/0617: {for beam forming} - H04B 7/063: {Parameters other than those covered in groups H04B7/0623 - H04B7/0634, e.g. channel matrix rank or transmit mode selection} - H04W 4/80: Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication - H04W 16/28: using beam steering - H04B 7/0413: MIMO systems - 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 radio network node (10) for downlink signal transmission to a user equipment (12) over an adaptively selected beam is presented. The radio network node (10) is configured to transmit, over different beams, different beam selection signals (15) that are respectively configured to prompt a response (16) from the user equipment (12) on different uplink radio resources (17). The radio network node (10) is configured to receive, from the user equipment (12), a response (16) over a responsive radio resource of the uplink radio resources (17). The radio network node (10) is further configured to select, from the different beams, a beam over which was transmitted a beam selection signal configured to prompt a response (16) on the responsive uplink radio resource, and transmit a downlink signal to the user equipment (12) over the selected beam. ## Claims ### Claim 1 A method, implemented by a radio network node, for downlink signal transmission to a user equipment over an adaptively selected beam, the method comprising: transmitting, over different beams, different beam selection signals that are respectively configured to prompt a response from the user equipment on different uplink radio resources, wherein the different beam selection signals comprise uplink grants that assign the user equipment the different uplink radio resources for uplink transmission, the beam selection signal serving a dual purpose of uplink grant and adaptive beam selection, wherein transmitting the different beam selection signals comprises transmitting the different beam selection signals over the different beams in a randomly ordered sequence; receiving, from the user equipment, a response over a responsive radio resource of the uplink radio resources; selecting, from the different beams, a beam over which a beam selection signal configured to prompt a response on the responsive uplink radio resource is transmitted; and transmitting a downlink signal to the user equipment over the selected beam. ### Claim 2 (depends on 1) The method of claim 1, wherein the different beam selection signals comprise paging signals transmitted to the user equipment in different paging occasions. ### Claim 3 (depends on 1) The method of claim 1, wherein the different uplink radio resources comprise different time resources on a random access channel. ### Claim 4 (depends on 1) The method of claim 1, wherein the different uplink radio resources comprise different dedicated radio resources on an uplink data channel that is shared by multiple user equipments. ### Claim 5 (depends on 1) The method of claim 1, further comprising determining one or more transmission parameters for transmission of the downlink signal based on the selecting, and transmitting the downlink signal using the one or more transmission parameters. ### Claim 6 (depends on 5) The method of claim 5, wherein the determining comprises determining the one or more transmission parameters based on a beamforming gain realizable with the selected beam. ### Claim 7 (depends on 1) The method of claim 1, wherein the downlink signal conveys a data block, and wherein the one or more transmission parameters include a number of repetitions of the data block to transmit. ### Claim 8 (depends on 1) The method of claim 1, wherein the one or more transmission parameters include a modulation and coding scheme. ### Claim 9 (depends on 1) The method of claim 1, further comprising, prior to transmitting the beam selection signals, selecting, from multiple candidate sets of beams, the candidate set that includes the different beams by: transmitting, over the different candidate sets of beams, different set selection signals that are respectively configured to prompt a response from the user equipment on different uplink radio resources, wherein the same set selection signal is transmitted over each beam in any given candidate set of beams; receiving, from the user equipment, a response over a responsive radio resource of the uplink radio resources; and selecting, from the different candidate sets of beams, a candidate set over which was transmitted a set selection signal configured to prompt a response on the responsive uplink radio resource. ### Claim 10 (depends on 9) The method of claim 9, wherein the different candidate sets of beams each comprise non-overlapping beams, wherein the different beams comprise non-overlapping beams within the same candidate set. ### Claim 11 (depends on 1) The method of claim 1, further comprising, prior to transmitting the beam selection signals: transmitting, over different coarse beams, different coarse-beam selection signals that are respectively configured to prompt a response from the user equipment on different uplink radio resources; receiving, from the user equipment, a response over a responsive radio resource of the uplink radio resources; selecting, from the different coarse beams, a coarse beam over which was transmitted a coarse-beam selection signal configured to prompt a response on the responsive uplink radio resource; and selecting the different beams as different fine beams within a beam footprint of the selected coarse beam. ### Claim 12 (depends on 1) The method of claim 1, further comprising, prior to transmitting the beam selection signals: transmitting, over different non-overlapping beams, different non-overlapping beam selection signals that are respectively configured to prompt a response from the user equipment on different uplink radio resources; receiving, from the user equipment, a response over a responsive radio resource of the uplink radio resources; selecting, from the different non-overlapping beams, a non-overlapping beam over which was transmitted a non-overlapping-beam selection signal configured to prompt a response on the responsive uplink radio resource; selecting the different beams as different overlapping beams that each overlap with at least one other of the different beams and with a beam footprint of the selected non-overlapping beam; and wherein selecting from the different beams is further based on uplink measurements by the user equipment. ### Claim 13 (depends on 1) The method of claim 1, further comprising estimating a location of the user equipment based on the selected beam. ### Claim 14 (depends on 1) The method of claim 1, wherein the downlink signal comprises a narrowband Internet of Things (NB-IoT) signal. ### Claim 15 A radio network node for downlink signal transmission to a user equipment over an adaptively selected beam, the radio network node comprising: processing circuitry; memory containing instructions executable by the processing circuitry whereby the radio network node is operative to: transmit, over different beams, different beam selection signals that are respectively configured to prompt a response from the user equipment on different uplink radio resources, wherein the different beam selection signals comprise uplink grants that assign the user equipment the different uplink radio resources for uplink transmission, the beam selection signal serving a dual purpose of uplink grant and adaptive beam selection wherein transmitting the different beam selection signals comprises transmitting the different beam selection signals over the different beams in a randomly ordered sequence; receive, from the user equipment, a response over a responsive radio resource of the uplink radio resources; select, from the different beams, a beam over which a beam selection signal configured to prompt a response on the responsive uplink radio resource is transmitted; and transmit a downlink signal to the user equipment over the selected beam. ### Claim 16 A non-transitory computer readable recording medium storing a computer program product for controlling a radio network node for downlink signal transmission to a user equipment over an adaptively selected beam, the computer program product comprising software instructions which, when run on processing circuitry of the radio network node, causes the radio network node to: transmit, over different beams, different beam selection signals that are respectively configured to prompt a response from the user equipment on different uplink radio resources, wherein the different beam selection signals comprise uplink grants that assign the user equipment the different uplink radio resources for uplink transmission, the beam selection signal serving a dual purpose of uplink grant and adaptive beam selection, wherein transmitting the different beam selection signals comprises transmitting the different beam selection signals over the different beams in a randomly ordered sequence; receive, from the user equipment, a response over a responsive radio resource of the uplink radio resources; select, from the different beams, a beam over which a beam selection signal configured to prompt a response on the responsive uplink radio resource is transmitted; and transmit a downlink signal to the user equipment over the selected beam.