Diplex Doppler radar for automotive obstacle detection

The usefulness of radar as an automotive obstacle detection system is currently being investigated. Possible applications of such a system presently are automatic braking and air bag actuation and eventually the totally automatic highway. One type of radar having possible potential for these short range applications is diplex Doppler radar. The microwave and electronic circuits basic to a diplex Doppler radar obstacle detection system are described in this paper. The system provides Analog outputs proportional to range, velocity, and time to impact relative to an obstacle, as well as indicating whether the velocity is opening or closing.