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Optimal design of emission waveform for acoustic scattering test under multipath interference

In order to reduce the impact of multi-path interference in the underwater target sound scattering test, the design of different forms of waveform such as CW-LFM+,CW- LFM-,CW-HFM+ and CW-HFM- are mainly studied in this paper, the bellhop model is used to simulate the shallow sea multi-path propagation environment, and the one-way attenuation and two-way impulse response of the shallow sea multi-path channel are calculated. Based on this, the scattered signal of the point target after the combined signal passes through the shallow sea two-way channel is calculated, and according to the time-domain waveform and time-frequency diagram of the scattered signal of the simulated point target, the validity of model selection and parameter setting is verified. The ambiguity graph and contour line of the analog signal and the measured signal are calculated, so the transmission waveform with better time-frequency resolution can be selected, which provides support for the detection of the sound scattering signal of complex targets under multipath interference.