Amplitude and phase calibration at a transmitter chip in an antenna array

Patent metadata

Field	Value
Publication number	US-2019109627-A1
Application number	US-201816206196-A
Country	US
Kind code	A1
Filing date	Nov 30, 2018
Priority date	May 4, 2017
Publication date	Apr 11, 2019
Grant date	—

Abstract

Select, from transmit paths within the transmitter chip, a first transmit path for a first transmit signal and a second transmit path for a second transmit signal. The transmit paths are associated with a plurality of antenna elements of an antenna array. Determine of an added signal and/or a subtracted signal associated with the first transmit signal and the second transmit signal. Determine at least one of a first signal strength value of the added signal or a second signal strength value of the subtracted signal. Adjust a first signal parameter of the second transmit signal relative to a corresponding first signal parameter of the first transmit signal until the first signal strength value is a first value or the second signal strength value is a second value. Calibrate an offset of the corresponding first signal parameter based on the adjusted first signal parameter in the second transmit path.

First claim

What is claimed is:

1 . A calibration system, comprising:
one or more circuits in a transmitter chip, wherein the one or more circuits are configured to:
select, from a plurality of transmit paths within the transmitter chip, a first transmit path for a first transmit signal and a second transmit path for a second transmit signal,
wherein the plurality of transmit paths are associated with a plurality of antenna elements of an antenna array;
determine at least one of an added signal or a subtracted signal associated with the first transmit signal and the second transmit signal;
determine at least one of a first signal strength value of the added signal or a second signal strength value of the subtracted signal;
adjust a first signal parameter of the second transmit signal in the second transmit path relative to a corresponding first signal parameter of the first transmit signal in the first transmit path until the first signal strength value of the added signal is a first value or the second signal strength value of the subtracted signal is a second value; and
calibrate an offset of the corresponding first signal parameter based on the adjusted first signal parameter in the second transmit path.

2 . The calibration system according to claim 1 , wherein the one or more circuits in the transmitter chip are further configured to transmit an output signal, via an antenna element of the plurality of antenna elements, with the calibrated offset of the corresponding first signal parameter.

3 . The calibration system according to claim 1 , wherein the one or more circuits are further configured to:
calibrate a value of a second signal parameter of the second transmit signal based on a matching of the second signal parameter in the second transmit path relative to a corresponding second signal parameter in the first transmit path; and transmit an output signal, via an antenna element of the plurality of antenna elements, with the calibrated offset of the corresponding first signal parameter and the calibrated value of the second signal parameter.

4 . The calibration system according to claim 1 , wherein the selected first transmit path and the selected second transmit path are adjacent.

5 . The calibration system according to claim 1 , wherein the selection of the first transmit path and the second transmit path is based on round-robin method.

6 . The calibration system according to claim 3 , wherein the adjustment of the first signal parameter of the second transmit signal is independent of an adjustment of the second signal parameter of the second transmit signal.

7 . The calibration system according to claim 1 , wherein the one or more circuits in the transmitter chip are further configured to determine the added signal based on addition of the first transmit signal and the second transmit signal.

8 . The calibration system according to claim 1 , wherein the one or more circuits in the transmitter chip are further configured to determine the subtracted signal based on subtraction of the first transmit signal and the second transmit signal.

9 . The calibration system according to claim 1 , wherein the plurality of antenna elements of the antenna array are integrated in a plurality of antenna modules.

10 . The calibration system according to claim 1 , wherein the one or more circuits are integrated with a plurality of antenna modules.

11 . The calibration system according to claim 1 , wherein the one or more circuits in the transmitter chip are further configured to correct deviation of at least one signal parameter of each of the plurality of transmit paths associated with the plurality of antenna elements, and wherein the deviation is corrected based on the calibration.

12 . The calibration system according to claim 1 , wherein the one or more circuits in the transmitter chip are further configured to:
determine a feedback signal based on at least one of the added signal and the subtracted signal, wherein the feedback signal is obtained on a feedback path corresponding to the second transmit path of the second transmit signal, and wherein the calibration of the offset of the corresponding first signal parameter is based on the feedback signal.

13 . A calibration system, comprising:
one or more circuits in a first transmitter chip of a plurality of transmitter chips, wherein the one or more circuits are configured to:
receive, at an antenna element, at least one output signal from at least one second transmitter chip of the plurality of transmitter chips, wherein each of the at least one output signal comprise a calibrated offset of a signal parameter determined at a corresponding second transmitter chip;
add or subtract, at the antenna element, the received at least one output signal to determine at least one of an added signal or a subtracted signal;
determine at least one of a first signal strength value of the added signal or a second signal strength value of the subtracted signal; and
calibrate an offset of a first signal parameter of a second output signal based on an adjusted first signal parameter of the second output signal relative to a corresponding first signal parameter of a first output signal,
wherein the first signal parameter of the second output signal is adjusted until the first signal strength value of the added signal is a first value or the second signal strength value of the subtracted signal is a second value.

14 . The calibration system according to claim 13 , wherein the one or more circuits in the transmitter chip are further configured to:
calibrate a value of a second signal parameter of the second transmit signal based on a matching of the second signal parameter in the second transmit path relative to a corresponding second signal parameter in the first transmit path.

15 . The calibration system according to claim 13 , wherein the one or more circuits in the transmitter chip are further configured to adjust the first signal parameter of the second output signal relative to the corresponding first signal parameter of the first output signal to minimize the second signal strength value of a subtracted signal.

16 . A calibration system in an antenna array, comprising:
a transmitter chip configured to:
select, from a plurality of transmit paths within the transmitter chip, a first transmit path for a first transmit signal and a second transmit path for a second transmit signal, wherein the plurality of transmit paths are associated with a plurality of antenna elements of the antenna array;
adjust a first signal parameter of the second transmit signal relative to a corresponding first signal parameter of the first transmit path; and
calibrate an offset of the corresponding first signal parameter based on the adjusted first signal parameter in the second transmit path; and
a receiver chip configured to:
receive a plurality of output signals, transmitted by the transmitter chip, at a plurality of input interfaces of a plurality of receive paths;
select a first receive path and a second receive path from the plurality of receive paths in the receiver chip;
calibrate at least one signal parameter in the first receive path relative to the second receive path, based on maximized first signal strength value of addition of a first output signal and a second output signal of the plurality of output signals or minimized second signal strength value of subtraction of the first output signal and the second output signal; and
generate a signal based on the calibration.

17 . The calibration system accordin

Assignees

• Movandi Corp

Inventors

• Sridharan Kartik
• Rofougaran Ahmadreza
• Boers Michael
• Yoon Seunghwan
• Gharavi Sam
• Shin Donghyup
• Shirinfar Farid
• Wu Stephen
• Rofougaran Maryam

Classifications

• H04B17/12

  of transmit antennas, e.g. of the amplitude or phase · CPC title

• H04B17/11

  for calibration · CPC title

• H04B7/0656 Primary

  at the transmitter, e.g. error detection at base station · CPC title

• H04B17/14

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

• H04B7/0617 Primary

  for beam forming · CPC title