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:
Sep. 03, 1991
Filed:
Dec. 19, 1989
Jean-Pierre Tomasi, Brive, FR;
U.S. Philips Corporation, New York, NY (US);
Abstract
A low altitude radio altimeter of the FM/CW type which transmits a sawtooth frequency wave and has a transmitting and a receiving aerial. A beat frequency signal Fb.sub.t between the transmitted and received waves is produced at the output of a mixer. The altimeter includes means for digitizing Fb.sub.t at the rate of n samples per sawtooth, a first memory (M1) to store n.times.k samples S.sub.j.sup.i (where i varies from 1 to k and j varies from 1 to n), a second memory (M2) to store n sums ##EQU1## first computing means (PR) for determining ##EQU2## representative of Fb.sub.4, for storage in a third memory (M3), and additional computing and storage means (PR, M4) producing difference signals Fb.sub.t -Fb.sub.f.