Research on LFM pulse signal compression based on parametric array technology

Detection of underwater buried objects requires low-frequency wave as the detecting source and high-resolution imaging. Taken these into account, this paper proposes a method to process the linear frequency modulated signal (LFM) based on parametric array theory. The distortion of the LFM demodulated by the parametric array and corresponding matched filter are studied by numerical method. The numerical simulation indicates that the frequency bandwidth for the self-demodulation signal has been doubled relative to its original bandwidth when LFM is emitted from the parametric array. In this context, a simple modified matched filter is proposed to do pulse compression. Both the simulation and experiment prove that the proposed matched filter can guarantee the accuracy of pulse compression. Furthermore, there is no sidelobe after pulse compression.