US 11,942,694 B2
Self-calibration of antenna array system
Raihan Rafique, Lund (SE); and Jacob Mannerstråle, Malmö (SE)
Assigned to Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
Filed by Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
Filed on Sep. 29, 2021, as Appl. No. 17/489,289.
Application 17/489,289 is a continuation of application No. 16/486,416, granted, now 11,158,940, previously published as PCT/EP2017/055818, filed on Mar. 13, 2017.
Prior Publication US 2022/0094052 A1, Mar. 24, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. H01Q 3/26 (2006.01); H04B 17/13 (2015.01); H04B 17/14 (2015.01); H04B 17/19 (2015.01); H04B 17/21 (2015.01)
CPC H01Q 3/267 (2013.01) [H04B 17/13 (2015.01); H04B 17/14 (2015.01); H04B 17/19 (2015.01); H04B 17/21 (2015.01)] 30 Claims
OG exemplary drawing
 
1. A method of operation of a transceiver to perform self-calibration for a plurality of transmit, Tx, antenna elements and a plurality of receive, Rx, antenna elements in an antenna array, comprising:
performing gain measurements, GMTxiRxj, and phase measurements, ϕMTxiRxj, for a first selected pair of Tx antenna elements and two or more pairs of Rx antenna elements each pair of Rx antenna elements having symmetrical coupling properties with the first selected pair of Tx antenna elements, where the gain measurement GMTxiRxj and the phase measurement GMTxiRxj and the phase measurement ϕMTxiRxj are measured gain and phase at an output of a receiver compared to an input of a transmitter, when the receiver is coupled to a j-th Rx antenna element during reception of a signal transmitted by a transmitter coupled to an i-th Tx antenna element;
computing at least one relative gain value and at least one relative phase value for the first selected pair of Tx antenna elements;
repeating the performing and computing steps for a second selected pair of Tx antenna elements and two or more pairs of Rx antenna elements, each pair of Rx antenna elements also having symmetrical coupling properties with the second selected pair of Tx antenna elements;
normalizing the at least one relative gain value and the at least one relative phase value relative to a defined reference Tx antenna element to thereby provide gain and phase calibration values for the plurality of Tx antenna elements; and
applying the gain and phase calibration values at the transceiver.