US Patent No. 10,348,423

CALCULATING A VIRTUAL BORESIGHT VECTOR OF AN ANTENNA ARRAY


Patent No. 10,348,423
Issue Date July 09, 2019
Title Calculating A Virtual Boresight Vector Of An Antenna Array
Inventorship Radivoje Zarubica, Salt Lake City, UT (US)
Samuel C. Kingston, Salt Lake City, UT (US)
Merle L. Keller, Salt Lake City, UT (US)
Assignee L3 TECHNOLOGIES, INC., New York, NY (US)

Claim of US Patent No. 10,348,423

17. An angle of arrival system comprising:an angle of arrival node having an antenna array and a modem coupled to the antenna array; and
a calibration node that is configured to emit a signal;
wherein the modem is configured to perform the following:
generate a first measured covariance matrix for the signal when the calibration node is positioned at an arbitrary location;
generate a second measured covariance matrix for the signal when the calibration node is positioned at a permanent location different from the arbitrary location;
generate a measured difference covariance matrix from the first and second measured covariance matrices;
determine an angle difference between an angle of the arbitrary location relative to the antenna array and an angle of the permanent location relative to the antenna array;
for each of a number of assumed angles of the permanent location relative to the antenna array:
calculate a first estimated covariance matrix for the assumed angle;
calculate a second estimated covariance matrix for a corresponding angle that is offset from the assumed angle; and
generate an estimated difference covariance matrix from the first and second estimated covariance matrices;
compare the measured difference covariance matrix to each estimated difference covariance matrix to identify one of the estimated difference covariance matrices that most closely matches the measured difference covariance matrix; and
calculate, from the assumed angle that corresponds with the identified estimated difference covariance matrix, an angle between the antenna array and the calibration node.