US 12,355,519 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 Oct. 21, 2024, as Appl. No. 18/921,834.
Application 18/921,834 is a continuation of application No. 18/109,207, filed on Feb. 13, 2023, granted, now 12,166,546.
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 2025/0047333 A1, Feb. 6, 2025
This patent is subject to a terminal disclaimer.
Int. Cl. H04L 5/12 (2006.01); H04B 7/024 (2017.01); H04B 7/0452 (2017.01); H04B 7/0456 (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) a first plurality of antennas of the wireless transceiver station, where the first plurality of antennas includes more than 8 antennas; and
(b) hard-wired logic connected to each antenna in the first plurality of antennas, which when executed causes the wireless transceiver station to perform a method comprising steps of:
(1) receiving a plurality of uplink (UL) transmissions in frequency selective channels by a second plurality of antennas that is a subset or all of the first plurality of antennas from a third plurality of antennas of a plurality of user equipment devices (UEs);
(2) determining a plurality of UL channel state information (CSI) in response to each UL transmission sent by one antenna of the third plurality of antennas and received by one antenna of the second plurality of antennas;
(3) deriving a plurality of downlink (DL) CSI from the plurality of UL CSI based on UL/DL channel reciprocity;
(4) precoding a plurality of orthogonal frequency-division multiplexing (OFDM) radio signals using the plurality of DL CSI and a plurality of radio frequency (RF) calibrations for the second plurality of antennas; and
(5) transmitting the plurality of OFDM radio signals from the second plurality of antennas to create a plurality of concurrent, non-interfering channels each at a respective location of each antenna of the third plurality of antennas.