Frequency interrupt continuous transmit active sonar transmission and signal processing technique

Abstract From the Canadian patent

In a time continuous transmit active sonar system the frequency of the transmitted waveform is interrupted at predetermined intervals so that a frequency discontinuity in the transmitted waveform occurs at each interruption. The starting and ending frequencies at the beginning and end of the interruptions provide indications for properly resolving the range/Doppler ambiguity that is inherent in prior continuous transmit sonar systems. The transmitted signal may be frequency modulated. Further the frequency of the transmitted waveform may be rapidly changed and/or multiple frequency waveforms may be transmitted within the same time interval. An existing passive sonar detection system may be …