# US 10,122,426 B2 · Method for beam steering in multiple-input multiple-output system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,122,426 B2 - Document ID: US10122426B2 - Status: Granted - Kind: B2 - Application number: 15/204,477 - Filed: 2016-07-07 - Published: 2017-01-26 - Granted: 2018-11-06 - Earliest claimed: 2015-07-20 - Assignees: Centre of Excellence in Wireless Technology; Indian Institute of Technology Madras - Applicants: Centre of Excellence in Wireless Technology; Indian Institute of Technology Madras - Inventors: Jeniston Deviraj Klutto Milleth; Chandrasekaran Mohandoss; Sendilramkumar Devar; Thulasiram Jonna; Abhijeet Masal; Bhaskar Ramamurthi - Web page: https://patentgrep.com/patent/US10122426B2 ## CPC - H04B 7/0456: Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting - H04B 7/0408: using two or more beams, i.e. beam diversity - H04B 7/0469: {taking special antenna structures, e.g. cross polarized antennas into account} - H04B 7/0617: {for beam forming} - H04B 7/0626: {Channel coefficients, e.g. channel state information [CSI]} - H04B 7/0632: {Channel quality parameters, e.g. channel quality indicator [CQI]} - H04B 7/0634: {Antenna weights or vector/matrix coefficients} - H04B 7/06952: {Selecting one or more beams from a plurality of beams, e.g. beam training, management or sweeping} - H04B 7/086: {using weights depending on external parameters, e.g. direction of arrival [DOA], predetermined weights or beamforming} - H04W 16/28: using beam steering - H04B: TRANSMISSION - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract Embodiments herein provide a method for beam steering in a Multiple Input Multiple Output (MIMO) system. The method includes steering a transmit beam using a precoder matrix determined based on a plurality of parameters, wherein the transmit beam is formed using at least one of a weight of each antenna element, a number of antenna elements, and an inter-antenna element spacing. ## Claims ### Claim 1 A method for beam steering in a Multiple Input Multiple Output (MIMO) system, the method comprising: forming and transmitting, by a transmitter, a plurality of transmit beams to at least one receiver; obtaining, by the transmitter, at least one optimal transmit beam selected from the plurality of transmit beams by the at least one receiver and at least one of at least one Channel Quality Indicator (CQI) of at least one transmit beam from the plurality of transmit beams, at least one Channel State Information (CSI) of the at least one transmit beam from the plurality of transmit beams, and a location of the at least one receiver; and steering, by the transmitter, the at least one optimal transmit beam towards the at least one receiver based on the at least one optimal transmit beam selected from the plurality of transmit beams by the at least one receiver and the at least one of the at least one CQI of the at least one transmit beam from the plurality of transmit beams, the at least one CSI of the at least one transmit beam from the plurality of transmit beams, and the location of the at least one receiver. ### Claim 2 (depends on 1) The method of claim 1, further comprising: forming and transmitting, by the transmitter, a plurality of sub-transmit beams within the at least one optimal transmit beam to the at least one receiver, wherein the at least one sub-transmit beam is formed based on at least one of the at least one CQI of the at least one transmit beam from the plurality of transmit beams, the at least one CSI of the at least one transmit beam from the plurality of transmit beams, the optimal transmit beam selected from the plurality of transmit beams by the at least one receiver, and the location of the at least one receiver; obtaining, by the transmitter, at least one optimal sub-transmit beam selected from the plurality of sub-transmit beams by the at least one receiver and at least one of at least one CQI of the at least one sub-transmit beam from the plurality of sub-transmit beams, at least one CSI of the at least one sub-transmit beam from the plurality of sub-transmit beams, and the location of the at least one receiver; and steering, by the transmitter, at least one optimal sub-transmit beam towards the at least one receiver based on the at least one optimal sub-transmit beam selected from the plurality of sub-transmit beams by the at least one receiver and the at least one of the at least one CQI of the at least one sub-transmit beam from the plurality of sub-transmit beams, the at least one CSI of the at least one sub-transmit beam from the plurality of sub-transmit beams, and the location of the at least one receiver. ### Claim 3 (depends on 1) The method of claim 1, wherein steering the at least one transmit beam comprising combining at least two optimal transmit beams from the plurality of transmit beams using at least one precoder matrix when the at least two optimal transmit beams are reported by the at least one receiver. ### Claim 4 (depends on 1) The method of claim 1, further comprising: forming, by the transmitter, a plurality of sub-transmit beams within the at least one transmit beam based on the at least one optimal transmit beam selected from the plurality of transmit beams by the at least one receiver and at least one of the at least one CQI of the at least one transmit beam from the plurality of transmit beams, and the at least one CSI of the at least one transmit beam from the plurality of transmit beams; and steering, by the transmitter, at least one sub-transmit beam from the plurality of sub-transmit beams by dynamically cycling at least one precoder matrix over an allocated resource, wherein dynamic cycling is performed over at least one of a time resource and a frequency resource. ### Claim 5 (depends on 1) The method of claim 1, wherein the at least one transmit beam from the plurality of transmit beams which is associated with the at least one receiver is transmitted with a periodicity more than a periodicity of the at least one transmit beam from the plurality of transmit beams which is not associated with the at least one receiver. ### Claim 6 (depends on 1) The method of claim 1, wherein the at least one optimal transmit beam is a wider transmit beam used to transmit at least one of broadcast signal and control signal to the at least one receiver. ### Claim 7 (depends on 2) The method of claim 2, wherein steering the at least one sub-transmit beam comprising combining at least two sub-transmit beams from the plurality of sub-transmit beams using at least one precoder matrix when the at least two optimal sub-transmit beams are reported by the at least one receiver. ### Claim 8 (depends on 2) The method of claim 2, wherein the at least one optimal sub-transmit beam is a narrow transmit beam used to transmit data signals to the at least one receiver. ### Claim 9 A transmitter for beam steering in a Multiple Input Multiple Output (MIMO) system, the transmitter comprising: a memory; and a processor, coupled to the memory, configured to: form and transmit a plurality of transmit beams to at least one receiver; obtain at least one optimal transmit beam selected from the plurality of transmit beams by the at least one receiver and at least one Channel Quality Indicator (CQI) of at least one transmit beam from the plurality of transmit beams, at least one Channel State Information (CSI) of the at least one transmit beam from the plurality of transmit beams, and a location of the at least one receiver; and steer the at least one optimal transmit beam towards the at least one receiver based on the at least one optimal transmit beam selected from the plurality of transmit beams by the at least one receiver and the at least one of the at least one CQI of the at least one transmit beam from the plurality of transmit beams, the at least one CSI of the at least one transmit beam from the plurality of transmit beams, and the location of the at least one receiver. ### Claim 10 (depends on 9) The transmitter of claim 9, wherein the processor is further configured to: form and transmit a plurality of sub-transmit beams within the at least one optimal transmit beam to the at least one receiver, wherein the at least one sub-transmit beam is formed based on at least one of the at least one CQI of the at least one transmit beam from the plurality of transmit beams, the at least one CSI of the at least one transmit beam from the plurality of transmit beams, and the at least one optimal transmit beam selected from the plurality of transmit beams by the at least one receiver, and the location of the at least one receiver, obtain at least one optimal sub-transmit beam selected from the plurality of sub-transmit beams by the at least one receiver and at least one of at least one CQI of the at least one sub-transmit beam from the plurality of sub-transmit beams, at least one CSI of the at least one sub-transmit beam from the plurality of sub-transmit beams, and the location of the at least one receiver, and steer at least one optimal sub-transmit beam towards the at least one receiver based on the at least one optimal sub-transmit beam selected by the at least one receiver and the at least one of the at least one CQI of the at least one sub-transmit beam from the plurality of sub-transmit beams, the at least one CSI of the at least one sub-transmit beam from the plurality of sub-transmit beams, and the location of the at least one receiver. ### Claim 11 (depends on 9) The transmitter of claim 9, wherein steering the at least one transmit beam comprising combining at least two optimal transmit beams from the plurality of transmit beams using at least one precoder matrix when the at least two optimal transmit beams are reported by the at least one receiver. ### Claim 12 (depends on 9) The transmitter of claim 9, wherein the processor is further configured to: form a plurality of sub-transmit beams within the at least one transmit beam based on at least one of the optimal transmit beam selected by the at least one receiver and at least one of at least one CQI of the at least one transmit beam from the plurality of transmit beams and the at least one CSI of the at least one transmit beam from the plurality of transmit beams; and steer at least one sub-transmit beam from the plurality of sub-transmit beams by dynamically cycling at least one precoder matrix over an allocated resource, wherein dynamic cycling is performed over at least one of a time resource and a frequency resource. ### Claim 13 (depends on 9) The transmitter of claim 9, wherein the at least one transmit beam from the plurality of transmit beams which is associated with the at least one receiver is transmitted with a periodicity more than a periodicity of the at least one transmit beam from the plurality of transmit beams which is not associated with the at least one receiver. ### Claim 14 (depends on 10) The transmitter of claim 10, wherein steering the at least one sub-transmit beam comprising combining at least two sub-transmit beams from the plurality of sub-transmit beams using at least one precoder matrix when the at least two optimal sub-transmit beams are reported by the at least one receiver. ### Claim 15 (depends on 9) The transmitter of claim 9, wherein the at least one optimal transmit beam is a wider transmit beam used to transmit at least one of broadcast signal and control signal to the at least one receiver. ### Claim 16 (depends on 10) The transmitter of claim 10, wherein the at least one optimal sub-transmit beam is a narrow transmit beam used to transmit data signal to the at least one receiver.