Systems and methods for self-calibration of an analog beamforming transceiver

Patent metadata

Field	Value
Publication number	US-11469498-B2
Application number	US-201716645845-A
Country	US
Kind code	B2
Filing date	Sep 15, 2017
Priority date	Sep 15, 2017
Publication date	Oct 11, 2022
Grant date	Oct 11, 2022

Abstract

Systems and methods are disclosed herein for self-calibration of an analog beamforming transceiver. In some embodiments, a method of operation of a self-calibration subsystem of an analog beamforming transceiver comprises, for each of multiple receive antenna elements for each of multiple transmit beam directions: transmitting a signal in the transmit beam direction via multiple transmit antenna elements of a second polarization and obtaining a measurement value for a received signal received via the receive antenna element of a first polarization responsive to the transmitted signal. The method further comprises computing calibration values for the receive antenna elements of the first polarization and calibration values for the transmit antenna elements of the second polarization based on the obtained measurement values. The method further comprises applying the calibration values for the receive antenna elements of the first polarization and the calibration values for the transmit antenna elements of the second polarization.

First claim

What is claimed is:

1. A method of operation of a self-calibration subsystem of an analog beamforming transceiver to perform self-calibration of antenna elements comprised in the analog beamforming transceiver, comprising:
for each receive antenna element of a plurality of receive antenna elements of a first polarization, the plurality of receive antenna elements of the first polarization being all or a subset of all receive antenna elements of the first polarization:
for each transmit beam direction of a plurality of transmit beam directions for a second polarization, the plurality of transmit beam directions for the second polarization being all or a subset of all transmit beam directions for the analog beamforming transceiver for the second polarization:
transmitting a signal in the transmit beam direction via a plurality of transmit antenna elements of the second polarization, the plurality of transmit antenna elements of the second polarization being all or a subset of all transmit antenna elements of the second polarization; and
obtaining a measurement value for a received signal received via the receive antenna element of the first polarization responsive to the signal transmitted in the transmit beam direction via the plurality of transmit antenna elements of the second polarization;
computing calibration values for the plurality of receive antenna elements of the first polarization and calibration values for the plurality of transmit antenna elements of the second polarization based on the measurement values obtained for each of the plurality of receive antenna elements of the first polarization for each of the plurality of transmit beam directions for the second polarization and known coupling factors between the plurality of receive antenna elements of the first polarization and the plurality of transmit antenna elements of the second polarization; and
applying the calibration values for the plurality of receive antenna elements of the first polarization and the calibration values for the plurality of transmit antenna elements of the second polarization.

2. The method of claim 1 further comprising:
for each receive antenna element of a plurality of receive antenna elements of the second polarization, the plurality of receive antenna elements of the second polarization being all or a subset of all receive antenna elements of the second polarization:
for each transmit beam direction of a plurality of transmit beam directions for the first polarization, the plurality of transmit beam directions for the first polarization being all or a subset of all transmit beam directions for the analog beamforming transceiver for the first polarization:
transmitting a signal in the transmit beam direction via a plurality of transmit antenna elements of the first polarization, the plurality of transmit antenna elements of the first polarization being all or a subset of all transmit antenna elements of the first polarization; and
obtaining a measurement value for a received signal received via the receive antenna element of the second polarization responsive to the signal transmitted in the transmit beam direction via the plurality of transmit antenna elements of the first polarization;
computing calibration values for the plurality of receive antenna elements of the second polarization and calibration values for the plurality of transmit antenna elements of the first polarization based on the measurement values obtained for each of the plurality of receive antenna elements of the second polarization for each of the plurality of transmit beam directions for the first polarization and known coupling factors between the plurality of receive antenna elements of the second polarization and the plurality of transmit antenna elements of the first polarization; and
applying the calibration values for the plurality of receive antenna elements of the second polarization and the calibration values for the plurality of transmit antenna elements of the first polarization.

3. The method of claim 2 wherein:
the calibration values for the plurality of receive antenna elements of the first polarization are gain and phase correction values for the plurality of receive antenna elements of the first polarization that are normalized to gain and phase values for a reference receive antenna element of the first polarization;
the calibration values for the plurality of transmit antenna elements of the second polarization are gain and phase correction values for the plurality of transmit antenna elements of the second polarization that are normalized to gain and phase values for a reference transmit antenna element of the second polarization;
the calibration values for the plurality of receive antenna elements of the second polarization are gain and phase correction values for the plurality of receive antenna elements of the second polarization that are normalized to gain and phase values for a reference receive antenna element of the second polarization; and
the calibration values for the plurality of transmit antenna elements of the first polarization are gain and phase correction values for the plurality of transmit antenna elements of the first polarization that are normalized to gain and phase values for a reference transmit antenna element of the first polarization.

4. The method of claim 3 further comprising, prior to applying the calibration values for the plurality of receive antenna elements of the first polarization and the calibration values for the plurality of transmit antenna elements of the second polarization and applying the calibration values for the plurality of receive antenna elements of the second polarization and the calibration values for the plurality of transmit antenna elements of the first polarization:
determining whether any gain values for the plurality of transmit antenna elements of the first polarization exceed a maximum transmit gain of the analog beamforming transceiver; and
if any of the gain values for the plurality of transmit antenna elements of the first polarization exceed the maximum transmit gain, normalizing the gain values for the plurality of transmit antenna elements of the first polarization and an inverse of gain values for the plurality of receive antenna elements of the first polarization with the maximum transmit gain.

5. The method of claim 3 further comprising, prior to applying the calibration values for the plurality of receive antenna elements of the first polarization and the calibration values for the plurality of transmit antenna elements of the second polarization and applying the calibration values for the plurality of receive antenna elements of the second polarization and the calibration values for the plurality of transmit antenna elements of the first polarization:
determining whether any of the gain values for the plurality of receive antenna elements of the first polarization exceed a maximum receive gain of the analog beamforming transceiver; and
if any of the gain values for the plurality of receive antenna elements of the first polarization exceed the maximum receive gain, normalizing 410 the gain values for the plurality of receive antenna elements of the first polarization and an inverse of the gain values for the plurality of transmit antenna elements of the first polarization with the maximum receive gain.

6. The method of any one of claim 3 further comprising, prior to applying the calibration values for the plurality of receive antenna elements of the first polarization and the calibration values for the plurality of transmit antenna elements of the second polarization and applying the calibration values for the plurality of receive antenna elements of the second polarization and the calibration values for the plurality of transmit an

Assignees

• Ericsson Telefon Ab L M

Inventors

• Rafique Raihan

Classifications

• H04B17/14

  of the whole transmission and reception path, e.g. self-test loop-back · CPC title

• H01Q3/267 Primary

  Phased-array testing or checking devices · CPC title