This paper reports a new method to achieve high-resolution sub-bottom profiling, providing a scheme for the development of Parametric Array Sub-bottom Profiler (PSBP). The high-resolution sub-bottom profiling system is integrated using parametric transmitting array and vector hydrophone, series signal enhancement and high-resolution signal processing methods are proposed to obtain clear sub-bottom profiles. Based on the parametric array, a small-aperture high directivity beam with low frequency, broadband, and without sidelobes is realized, physically achieved high spatial resolution and temporal resolution. By using the vector hydrophone, a single side frequency doubling beamforming (SSFDB) method is used to significantly suppresses the impact of marine environmental noise and sea surface acoustic scattering, the detection resolution is improved due to the frequency doubling characteristics of SSFDB at the same time. Low order bidirectional differential arithmetic unit (LOBDAU) and coherent accumulator (CA) are combined to enhance the echo signal, and finally the high-resolution layering method (HRLM) based on peak detection gives a clear sub-bottom profile of the sediment. The benefits of the combined acoustic array design scheme and the researched signal processing methods had been experimentally evaluated, a clear sub-bottom profile with a semi buried sunken ship was obtained.
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