Multiple-frequency doppler radar - uses transmission of unique pulse between blocks of transmission pulses to eliminate multiple return echoes

摘要

A Doppler radar emits a unique pulse in the interval separating two blocks of transmission pulses at different frequencies. The signals from three generators (1, 2, 3) pass via a switching circuit (4) to a processing circuit (5) where they are modulated prior to amplification (6) and transmission. A circulator (7) route received signals to a particular analysis channel comprising a mixer (11) and detection and integration circuit (D, C). This demodulates the signals for a processing circuit (20) where they are encoded into digital signals for correlation and pulse compression. The fixed echos are removed and Doppler analysis effected.