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. 14, 1989
Filed:
Nov. 03, 1986
Nathan Freedman, West Newton, MA (US);
Wayne H Keene, South Natick, MA (US);
Albert V Jelalian, Bedford, MA (US);
Raytheon Company, Lexington, MA (US);
Abstract
A laser radar system wherein a beam of continuous wave (CW) electromagnetic energy is generated with frequency modulation (FM) and amplitude modulation (AM) being imposed thereon to produce an amplitude and frequency modulated, continuous wave beam of energy. The AM-FM CW beam is transmitted toward a selected target, portions of the transmitted beam being reflected by the target and received along with portions of the transmitted beam reflected by unselected targets and atmospheric clutter. A first signal is produced in response to the frequency modulation on the received beam portions reflected by the selected target, such first signal representing the approximate range of the selected target and substantially resolving the selected target from unselected targets and atmospheric clutter and having a relatively long ambiguous range interval. A second signal is produced in response to the amplitude modulation on the received beam portions reflected by the selected target, the second signal representing the accurate range of the selected target within a relatively short ambiguous range interval. The second signal provides poor resolution between the selected target and the unselected targets and atmospheric clutter. The first and second signals are combined to produce an output signal having the relatively high resolution and long ambiguous range interval of the first signal and providing the accurate selected target range measurement of the second signal.