Pulse doppler radar system - has variable sampling frequency evaluator circuit to resolve ambiguities

摘要

In order to eliminate ambiguities in distance and speed measurement a pulse doppler radar incorporates a variable frequency sampling generator (TG). Pulse signals of sampling frequency fT from a transmitter (S) are sent out by a transmitting aerial. Echo signals picked up by a receiving aerial (EA) are passed by a receiver (E) to an evaluating circuit (A). Resolution of ambiguities is achieved by evaluation of the relationship n = K f2T. RZ/fT where n is the order of ambiguity, K is a constant of proportionality, fT is the sampling frequency and RZ and fT are the time differentials of the distance of the object from the radar apparatus and the sampling frequency.