An unambiguous pulse radar procedure with high pulse-duration ratio

A new correlation concept for radar system is described which is completely unambiguous in spite of a pulse-duration ratio somewhat larger than 1:3. This method involves sending out a series of short pulses within a given period and correlating the reflected echoes with reference pulses of similar structure and identical periods. All spaces between the pulses of the reference pulse sequences and those of the transmitted sequences are derived from a periodic quasi-stochastic ternary number sequence. An application of the concept to a collision warning system for motor vehicles is demonstrated.