US 12,237,888 B2
Systems and methods for radio frequency calibration exploiting channel reciprocity in distributed input distributed output wireless communications
Antonio Forenza, San Francisco, CA (US); Fadi Saibi, Sunnyvale, CA (US); Timothy A. Pitman, San Francisco, CA (US); and Stephen G. Perlman, Palo Alto, CA (US)
Assigned to Rearden, LLC, Palo Alto, CA (US)
Filed by Rearden, LLC, Palo Alto, CA (US)
Filed on Jul. 22, 2024, as Appl. No. 18/779,453.
Application 18/779,453 is a continuation of application No. 18/109,207, filed on Feb. 13, 2023.
Application 18/109,207 is a continuation of application No. 17/498,666, filed on Oct. 11, 2021, granted, now 11,581,924, issued on Feb. 14, 2023.
Application 17/498,666 is a continuation of application No. 16/719,169, filed on Dec. 18, 2019, granted, now 11,146,313, issued on Oct. 12, 2021.
Application 16/719,169 is a continuation of application No. 13/844,355, filed on Mar. 15, 2013, granted, now 10,547,358, issued on Jan. 28, 2020.
Prior Publication US 2024/0380447 A1, Nov. 14, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. H04B 7/0456 (2017.01); H04B 7/024 (2017.01); H04B 7/0452 (2017.01); H04B 7/06 (2006.01); H04B 17/12 (2015.01); H04L 25/02 (2006.01)
CPC H04B 7/0452 (2013.01) [H04B 7/024 (2013.01); H04B 7/0456 (2013.01); H04B 7/0626 (2013.01); H04B 17/12 (2015.01); H04L 25/0224 (2013.01)] 30 Claims
OG exemplary drawing
 
1. A wireless transceiver station comprising:
(a) a first set of N antennas of the wireless transceiver station in a radio access network (RAN) within a coverage area, where N is an integer greater than 8; and
(b) hard-wired logic connected to each antenna in the first set of N antennas, which when executed causes the wireless transceiver station to perform a method comprising steps of:
(1) sending a plurality of training signals from at least a first antenna of the first set of N antennas to at least a second antenna of the first set of N antennas;
(2) processing the plurality of training signals to estimate a plurality of radio frequency calibration coefficients;
(3) determining uplink (UL) channel state information (CSI) in response to receiving a plurality of UL transmissions by one or more of the first set of N antennas from one or more of a second set of M antennas of a plurality of user equipment devices (UEs);
(4) preconditioning a matrix of UL CSI using the plurality of radio frequency calibration coefficients to obtain a matrix of downlink (DL) CSI; and
(5) based on the matrix of DL CSI, precoding a plurality of radio signals transmitted concurrently by the first set of N antennas, to cause the plurality of radio signals to deliberately interfere to create concurrent, non-interfering channels at a respective location of each antenna in the second set of M antennas.