Abstract: A frequency diversity receiver system operating over a predetermined bandwidth comprising a first mixer receiving two identical information signals widely separated in frequency, a stepping oscillator with a predetermined number of steps controlling the output frequency of said mixer, two frequency channels at the output of said mixer, the first of said channels having a broad bandwidth filter and the second having a narrow bandwidth filter, a second mixer receiving simultaneously the output of said second filter and the output signal of a sweeping oscillator, said sweeping oscillator having a preselected sweep, means to synchronize said sweeping oscillator and said stepping oscillator, a multiplier simultaneously receiving the output signals from said first filter and said second mixer, a bank of parallel filters and associated detectors receiving the output signals from said multiplier, each of said filters of said bank having a predetermined bandwidth.

Abstract: A receiver for detecting a double side-band noise like signal, in which the receiver is swept over a defined RF spectrum of interest, a phase inversion of the double side band signal is provided and multiplied with the received double side-band noise-like signal to produce an IF signal, and correlation circuitry is provided to produce an output whereby the presence of the double side-band noise like signal is detected, and controls the stopping of the sweep at said detection.