US 12,224,819 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. 15, 2024, as Appl. No. 18/773,255.
Application 18/773,255 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 2024/0405813 A1, Dec. 5, 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)] 22 Claims
OG exemplary drawing
 
1. A wireless transceiver station comprising:
a first plurality of more than eight antennas of a radio access network (RAN) within a coverage area,
wherein eight or more of the first plurality of antennas are configured to send a plurality of training signals between them;
wherein the training signals are processed to estimate a plurality of radio frequency (RF) calibration coefficients;
wherein the RF calibration coefficients are used to precondition a matrix of uplink (UL) channel state information (CSI) to obtain a matrix of downlink (DL) CSI;
the UL CSI is determined from a plurality of UL transmissions received by at least one antenna of the first plurality of antennas from one or more of a second plurality of antennas of one or more of a plurality of user equipment devices (UEs);
the matrix of DL CSI is used to precode a plurality of radio signals transmitted concurrently by the first plurality of antennas; and
the precoding causing the plurality of radio signals to deliberately interfere to create concurrent, non-interfering channels at one or more locations of the one or more of the second plurality of antennas of the one or more of the plurality of UEs.