The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 04, 2006
Filed:
Mar. 26, 2004
David R. Iny, Baltimore, MD (US);
Mark D. Stenoien, Columbia, MD (US);
Henry E. Lee, Ellicott City, MD (US);
David R. Iny, Baltimore, MD (US);
Mark D. Stenoien, Columbia, MD (US);
Henry E. Lee, Ellicott City, MD (US);
Northrop Grumman Corporation, Los Angeles, CA (US);
Abstract
An airborne radar interrogates tags on friendly ground vehicles, which when interrogated by a downlink signal from the radar, sends back a very low level uplink message signal that appears noise-like so as to avoid enemy detection and exploitation. This is achieved by retransmitting a time delayed and phase shifted version of the transmitted pulse from the radar. The digital RF tag captures every other pulse from the radar and transmits a digitally coded spread spectrum pulse back to the radar during every other intervening pulse which includes a pseudo random delay (range hop) and a pseudo random phase (direction).