FM CONTINUOUS WAVE RADAR AND ITS APPLICATION TO AN ALTIMETER

摘要

Apparatus for reducing the composite coupling signal in a frequency modulated, continuous wave radar having a single antenna and a duplexer includes a modulation signal generator coupled to a continuous wave oscillator to provide input to the duplexer. A directional coupler at the duplexer input provides input to an adjustable phase-shifter which provides a phase-shifted signal to an RF mixer. The RF mixer receives a second input from the output of the duplexer and provides a mixed signal. A level modulator having an adjustable control input receives a portion of the modulated signal from the modulation signal generator. The level modulator then provides an output to the audio amplifier which also receives the mixed signal from the RF mixer. The audio amplifier provides an output signal having reduced composite coupling signal components.