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Development of broadband high frequency sub-bottom profiler

A high frequency 1 sub-bottom profiler with a central frequency of 110KHz and a bandwidth of 30KHz was developed. The instrument has a better resolution than 5cm for the shallow layer of the seafloor and is used to detect acoustic characteristics of seafloor sediments. The instrument can eventually operate at 6000m depth. The test results show that the transmitter and receiver of the instrument work stably, the pulse compression waveform of wideband frequency modulated signal is effective, the resolution is high, and the indicators basically meet the expectation. The sediment detection depth in the fine grain area is more than 1 meter, which satisfies the requirement of geotechnical mechanics to the detection depth of sedimentary structure.