LAUSR

Abstract Focusing on the potential value of narrow directivity of parametric sonar in underwater acoustic communication, a broadband recursive filtering modulation method is proposed in this paper to generate parametric array excitation signal. The idea is to design the transient waveform by reversing the relationship between the envelope of original wave and difference frequency wave with the recursive filter. The method could process broadband and unknown arbitrary waveform signal (such as voice, image and video signal) in real time to get almost undistorted packets with low computation complexity. The feasibility and efficiency of the proposed method are verified by pool and trial experiments. The single carrier underwater acoustic communication system based on parametric array is applied to test the method in a distributed network. Performance of the system is improved effectively since the approximately distortion-free and narrow directivity compared with the conventional broadcast underwater acoustic communication system in Dalian sea trial.