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. 30, 2002
Filed:
May. 11, 2001
Leo G. Maloratsky, Indialantic, FL (US);
Rockwell Collins, Inc., Cedar Rapids, IA (US);
Abstract
A single antenna FM radio altimeter operates in continuous wave (CW) and interrupted continuous wave (ICW) modes to provide an altitude indication. An altimeter transmitter generates a constant FM period CW signal below a critical altitude and a variable FM period ICW signal above the critical altitude. The single antenna, connected to the transmitter and receiver, radiates and receives the CW and the ICW signals. The receiver provides a beat frequency signal. A processor compares the beat frequency signal and the variable FM period signal to critical altitude reference signals and switches the altimeter between the modes accordingly. The processing function provides the transmitter a constant period modulation signal below the critical altitude and a variable FM period signal above the critical altitude. The processing function provides the altitude indication from the beat frequency signal below the critical altitude and from the variable FM period signal above the critical altitude.