The generalized sinusoidal frequency modulated waveform for high duty cycle active sonar

High Duty Cycle Active Sonar (HDCAS) continuously transmits waveforms and processes target echoes to revisit the target scene more frequently than conventional pulsed active sonar. The main challenge in HDCAS waveform design is simultaneously maintaining a large bandwidth and a high revisit rate. This research proposes a new diverse pulse train for HDCAS that is composed of Generalized Sinusoidal Frequency Modulated (GSFM) waveforms. Since each GSFM waveform in the pulse train is nearly orthogonal to the others, each pulse can be processed separately providing the high target revisit rates necessary for HDCAS while also attaining large instantaneous bandwidth.