Abstract: A “cross-eye” type radar countermeasure in which both of the waveforms of the illuminating signal from the enemy radar received at spaced locations on the carrying vehicle is propagated through a common dual channel to balance the effect of unintentional phase distortion. Two common channels receive the radar waveform and store the same in a delay line. During the stored interval the switches at the ends of the two common channels are transitioned to the non-stable state connecting the output end of one common channel to the input end of the other, and vice versa. Both waveforms then enter the delay line of the subsequent common channel and the switches change to the stable state whereupon each waveform is retransmitted at the other spaced location on the carrying vehicle.

Abstract: An automatic adaptive sensitivity time control for a ground mapping radar comprises the dynamic range of radar returns for presentation on a video display. A feedback loop including a differential amplifier senses the magnitude of a signal presented to a limit amplifier and compares the same with a clutter threshold reference potential. A low-pass filter in the feedback loop then smooths or averages the clutter deviation from the reference potential to adjust the clutter level out of a log IF amplifier so that the nominal clutter signal level of close-in returns does not exceed a predetermined magnitude. A second embodiment includes a dual time constant filter in the feedback loop. A comparator circuit senses the leading edge of clutter return signals and switches the feedback loop to its faster time constant mode allowing dynamic compression of smaller time constant pulses.