Passive target detection and identification system
AssigneeLockheed Martin Corporation
InventorWilliam L. Rubin
Life of this patent
Estimating the term…
Abstract
A passive target positioning system utilizes three stations positioned on a linear baseline with a central master station positioned predetermined distances from two slave stations. Angle to the target is determined from the time differences of arrival at the master station and each of the slave stations. Range to the target, in one embodiment, is determined from the difference of the two time difference of arrival measurements and the angle-to-target, while in a second embodiment from the time differences of arrival. A scannable antenna with frequency selection capability provides a spatial sector and frequency band selectivity.
Claims11
A passive target location system operative on signals received from target mounted radiation sources comprising:
- first means for receiving emissions from sources located on at least one target;
- second and third means positioned on a line through said first receiving means at preselected distances on either side thereof for receiving emissions from said sources located on said at least one target;
- means for determining time of arrival of an emission received from at least one of said sources at said second and third receiving means relative to time of arrival of said emission received at said first receiving means;
- means for unambiguously determining angles of arrival of said emission at said second and third receiving means from times of arrivals at said second and third receiving means relative to said first receiving means, said angles of arrival being unambiguously determined with accuracies that are dependent on said preselected distances, said accuracies improving with increases in said distances and being independent of wavelengths of said emissions;
- and
- means for unambiguously determining range and angle-to-target from said angles of arrival and said preselected separation distances.
A passive target location system operative on signals received from target mounted radiation sources comprising:
- first means for receiving emissions from sources located on at least one target;
- second and third means positioned on a line through said first receiving means on either side thereof at preselected distances therefrom for receiving emissions from said sources located on said at least one target;
- means for determining time of arrival of an emission from at least one of said sources at said second and third receiving means relative to time of arrival of said emission at said first receiving means;
- means for determining, from said time of arrival at said second and third receiving means relative to said first receiving means, unambiguous angles of arrival of said emissions at said second and third receiving means, said angles of arrival being unambiguously determined with accuracies that are dependent on said preselected distances, said accuracies improving with increases in said distances and being independent of wavelengths of said emissions;
- means for determining a difference between said relative time of arrival at said second and third receiving means;
- means for determining angle-to-target from said angles of arrival and said preselected separation distances;
- and
- means for determining range-to-target from said difference of said relative times of arrival and said angle-to-target.
Dependencies are inferred from the claim text.