# US 2018/0026694 A1 · Method and apparatus for communication based on common feedback information in multiple antenna system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2018/0026694 A1 - Document ID: US20180026694A1 - Status: Published application - Kind: A1 - Application number: 15/550,692 - Filed: 2015-02-13 - Published: 2018-01-25 - Earliest claimed: 2015-02-13 - Applicants: LG Electronics Inc. - Inventors: Hyunsoo KO; Heejeong CHO; Hyeyoung CHOI; Ilmu BYUN; Kungmin PARK - Web page: https://patentgrep.com/patent/US20180026694A1 ## CPC - H04B 7/0617: {for beam forming} - H04B 7/0632: {Channel quality parameters, e.g. channel quality indicator [CQI]} - H04B 7/0639: {Using selective indices, e.g. of a codebook, e.g. pre-distortion matrix index [PMI] or for beam selection} - H04B 7/0658: {Feedback reduction} - H04B 7/0667: {of delayed versions of same signal (using space-time coding H04L1/0618)} - H04B 7/0689: {using different transmission schemes, at least one of them being a diversity transmission scheme} - H04L 1/0009: {by adapting the channel coding (H04L1/1812 takes precedence)} - H04L 1/0026: {Transmission of channel quality indication} - H04L 1/0618: {Space-time coding} - H04L 1/0625: {Transmitter arrangements} - H04B 7/0645: {Variable feedback} - H04B: TRANSMISSION - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract Disclosed is method and apparatus for communication using common feedback information in multiple antenna system. According to this method, a receiving side device receives rank Ni signals from a transmitting side device with a first type multiple antenna transmission scheme at a first receiving opportunity, and receives rank Nj signals from the transmitting side device with a second type multiple antenna transmission scheme at a second receiving opportunity, where Ni>Nj. The feedback information of this method is common feedback information comprising a combination of a first feedback information for the rank Ni signals and a second feedback information for the rank Nj signals. For this, the first type multiple antenna transmission scheme uses the second type multiple antenna transmission scheme for transmission of rank Nj signals among the rank Ni signals received at the first receiving opportunity. ## Claims ### Claim 1 A method for a transmitting side device to transmit signals with multiple antennas in a wireless communication system, the method comprising: transmitting rank Ni signals to a receiving side device with a first type multiple antenna transmission scheme at a first transmission opportunity; receiving feedback information from the receiving side device in response to the transmitted rank Ni signals; transmitting rank Nj signals to the receiving side device with a second type multiple antenna transmission scheme at a second transmission opportunity, wherein Ni>Nj, wherein the first type multiple antenna transmission scheme uses the second type multiple antenna transmission scheme for transmitting rank Nj signals among the transmitted rank Ni signals at the first transmission opportunity, and wherein transmitting the Nj signals at the second transmission opportunity is based on a consideration of a part of the feedback information received in response to the rank Ni signals transmitted at the first transmission opportunity. ### Claim 2 (depends on 1) The method of claim 1, wherein Ni is 2 and Nj is 1, wherein the first type multiple antenna transmission scheme is dual stream beamforming, and wherein the second type multiple antenna scheme is Alamouti transmission based on the dual stream beamforming. ### Claim 3 (depends on 1) The method of claim 1, wherein the first type multiple antenna transmission scheme uses a first precoder corresponding to a first precoding matrix, wherein the second type of multiple antenna transmission scheme uses a second precoder corresponding to a second precoding matrix, and wherein the first precoding matrix comprises all of columns of the second precoding matrix. ### Claim 4 (depends on 3) The method of claim 3, wherein the feedback information comprises: an index indicating the first precoding matrix, channel quality information for the rank Ni signals, and channel quality information for the rank Nj signals. ### Claim 5 (depends on 1) The method of claim 1, wherein the feedback information comprises a combination of a first feedback information for the rank Ni signals and a second feedback information for the rank Nj signals. ### Claim 6 (depends on 1) The method of claim 1, wherein the transmitting side device comprises Nk transmission antennas, and wherein Ni is an integer from 2 to Nk. ### Claim 7 (depends on 1) The method of claim 1, wherein the transmitting side device comprises a base station employing a massive MIMO scheme. ### Claim 8 A method for a receiving side device to transmit feedback information in a wireless communication system, the method comprising: receiving rank Ni signals from a transmitting side device with a first type multiple antenna transmission scheme at a first receiving opportunity; receiving rank Nj signals from the transmitting side device with a second type multiple antenna transmission scheme at a second receiving opportunity, wherein Ni>Nj; and transmitting feedback information to the transmitting side device, wherein the first type multiple antenna transmission scheme uses the second type multiple antenna transmission scheme for transmission of rank Nj signals among the rank Ni signals received at the first receiving opportunity, and wherein the feedback information comprises a combination of a first feedback information for the rank Ni signals and a second feedback information for the rank Nj signals. ### Claim 9 (depends on 8) The method of claim 8, wherein the first type multiple antenna transmission scheme uses a first precoder corresponding to a first precoding matrix, wherein the second type of multiple antenna transmission scheme uses a second precoder corresponding to a second precoding matrix, and wherein the first precoding matrix comprises all of columns of the second precoding matrix. ### Claim 10 An transmitting side device for transmitting signals in a wireless communication system, the device comprising: multiple antennas; a RF unit in connection with the multiple antennas; and a processor connected to the RF unit and configured to control the RF unit to transmit rank Ni signals with a first type multiple antenna transmission scheme, and to transmit rank Nj signals with a second type multiple antenna transmission scheme, and to receive feedback information from a receiving side device, wherein Ni>Nj, wherein the first type multiple antenna transmission scheme uses the second type multiple antenna transmission scheme for transmitting rank Nj signals among the rank Ni signals at a transmission of the rank Ni signals, and wherein transmitting independent Nj signals is based on a consideration of a part of the feedback information received in response to the previously transmitted rank Ni signals. ### Claim 11 (depends on 10) The device of claim 10, wherein the first type multiple antenna transmission scheme uses a first precoder corresponding to a first precoding matrix, wherein the second type of multiple antenna transmission scheme uses a second precoder corresponding to a second precoding matrix, and wherein the first precoding matrix comprises all of columns of the second precoding matrix. ### Claim 12 (depends on 10) The device of claim 10, wherein the feedback information comprises a combination of a first feedback information for the rank Ni signals and a second feedback information for the rank Nj signals. ### Claim 13 A receiving side device for transmitting feedback information in a wireless communication system, the device comprising: a RF unit receiving rank Ni signals from a transmitting side device with a first type multiple antenna transmission scheme, and receiving rank Nj signals from the transmitting side device with a second type multiple antenna transmission scheme, wherein Ni>Nj; and and transmitting feedback information to the transmitting side device, wherein the first type multiple antenna transmission scheme uses the second type multiple antenna transmission scheme for transmission of rank Nj signals among the rank Ni signals; and a processor connected to the RF unit and configured to construct the feedback information to comprise a combination of a first feedback information for the rank Ni signals and the rank Nj signals. ### Claim 14 (depends on 13) The device of claim 13, wherein the first type multiple antenna transmission scheme uses a first precoder corresponding to a first precoding matrix, wherein the second type of multiple antenna transmission scheme uses a second precoder corresponding to a second precoding matrix, and wherein the first precoding matrix comprises all of columns of the second precoding matrix.