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:
Mar. 04, 1997
Filed:
Apr. 19, 1995
Barry L Stann, Silver Spring, MD (US);
William C Ruff, Baltimore, MD (US);
Zoltan G Sztankay, Rockville, MD (US);
The United States of America as represented by the Secretary of the Army, Washington, DC (US);
Abstract
In a high range resolution ladar, a chirp signal waveform is propagated as a divergent laser light waveform and the target reflected return is collected and converted to a current proportional to power. An undelayed chirp signal is added in a mixer to the return current and then low pass filtered to recover a mixed intermediate frequency (IF) signal having a frequency proportional to the target range. Periodically, the light circuit is interrupted and the chirp signal is processed through the mixer and low pass filter without a target return current and this output, the mixer self-clutter, is stored. This stored self-clutter signal is subsequently subtracted from the mixed IF signal on a chirp by chirp basis to cancel the self-clutter produced by the mixer. The subtracted signal is then frequency analyzed to determine target range.