US Patent 7737886 Doppler radar systems

A frequency scanning radar system includes a frequency scanning radar controller for use in controlling a frequency generator, the frequency generator being arranged to generate a plurality of sets of signals, each set of signals having a different carrier frequency and comprising a sequence of modulation patterns, transmitted at a selected rate, wherein the radar controller is arranged to select the rate in dependence on the carrier frequency. The system also includes a signal processor arranged to derive tone data from received signals, wherein the signal processor is arranged to process the received signals at a rate dependent on the rate of transmission of the sequence of modulation patterns. Additionally, the system includes an audio system arranged to output audio data derived from signals received by the frequency scanning radar system by playback of the derived tone data at a constant rate.