Radar presentation simulator

Claim 1

A fast acting range tracker supplied with a sync input signal of a first frequency, and a video input signal, comprising; range gate means, for producing a bipolar square wave at a pulse repetition frequency equal to the frequency of said sync input signal, rectifier means, coupled to said range gate means, for blocking positive portions of said bipolar square wave, thereby providing negative voltage output signals, sawtooth generator means, coupled to said rectifier means, for producing a linear sawtooth voltage waveform, controlled by the negative voltage output signals, range comparator means, coupled to said sawtooth generator means having two inputs, a first of which is coupled to the output of said sawtooth generator means, for providing a track gate voltage which is proportional in magnitude to the difference between the magnitudes of the two input voltages applied thereto; range mixer means, coupled to the second input of said range comparator means, having a plurality of inputs for providing an output voltage whose magnitude is a function of the input signals, tracking gate means coupled to the output of said range comparator means, early and late gate means, having a video input signal and a track gate voltage input for providing discrimination in range with respect to said two input signals, wherein said early and late gate means include, a late gate delay means whose input is coupled to the output of said tracking gate means, a late gate generator means, whose input is coupled to the output of said late gate delay means, a late gate mixer means, having a plurality of inputs, one of which inputs is derived from the output of said late gate generator means, early gate generating means having an input which is coupled to the output of said range comparator means, and an early gate mixer having a plurality of inputs, one of which inputs is coupled to the output of said early gate generator means.