Patent ID: 6992614
Filing Date: 2006-01-31
Classification: G01S

Abstract:
1. A radar altimeter for determining an altitude of an aircraft, comprising: a first antenna; a second antenna; a transmitter coupled to said first antenna and operable to generate a radio signal at a modulation frequency and transmit said radio signal, via said first antenna, toward a ground surface for reflection therefrom to thereby propagate a reflected radio signal; and a receiver coupled to said second antenna and configured to receive, via said second antenna, said reflected radio signal and an antenna coupling signal generated between said first and said second antenna, the receiver operable to (i) determine said altitude of said aircraft based on said modulation frequency of said radio signal and a difference frequency derived from said radio signal and said reflected radio signal and (ii) control said transmitter so as to vary said modulation frequency of said radio signal based on said altitude of said aircraft, said receiver comprising: