A pulse doppler radar system for measuring the range to a target. The radar system alternately transmits a signal having a constant frequency and a signal modulated by a linearly-changing-frequency and receives an echo signal from a target. When a plurality of doppler frequencies derived from jet engine...http://www.google.fr/patents/US4920347?utm_source=gb-gplus-shareBrevet US4920347 - Pulse doppler radar system
