Abstract: A frequency correction for frequency difference of arrival geolocation of transmitted target signals may be provided. A frequency of a target signal may be determined at a first collector based upon a first reference timebase source. A frequency of the target signal may be determined at a second collector based upon a second reference timebase source. An observed frequency of a reference carrier signal based upon the first reference timebase source may be determined at the second collector based upon the second reference timebase source. A relative timebase error between the first collector and the second collector may be calculated based upon a difference between the intended frequency of the reference carrier signal and the observed frequency of the reference carrier signal. A corrected frequency difference for the target signal may be calculated based upon the relative timebase error and a proportional scaling factor.
Type:
Grant
Filed:
October 15, 2013
Date of Patent:
October 24, 2017
Assignee:
Zeta Associates, Inc.
Inventors:
John M. Holford, James M. Williams, Michael E. Glidewell
Abstract: A frequency correction for frequency difference of arrival geolocation of transmitted target signals may be provided. A frequency of a target signal may be determined at a first collector based upon a first reference timebase source. A frequency of the target signal may be determined at a second collector based upon a second reference timebase source. An observed frequency of a reference carrier signal based upon the first reference timebase source may be determined at the second collector based upon the second reference timebase source. A relative timebase error between the first collector and the second collector may be calculated based upon a difference between the intended frequency of the reference carrier signal and the observed frequency of the reference carrier signal. A corrected frequency difference for the target signal may be calculated based upon the relative timebase error and a proportional scaling factor.
Type:
Application
Filed:
October 15, 2013
Publication date:
April 17, 2014
Applicant:
Zeta Associates, Inc.
Inventors:
John M. Holford, James M. Williams, Michael E. Glidewell