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Parameter Estimation Method of Underwater Acoustic Chirp Spread Spectrum Signal

In non-cooperative underwater acoustic communication, there is a problem of insufficient accuracy in parameter estimation of Chirp spread spectrum signal. In this paper, a method combining short-time fractional Fourier transform and high-order cumulant is proposed to obtain the time-frequency distribution image of the signal, and then the Hough transform is used to process the image to get the parameter information of the signal. Simulation and measurement results show that the proposed method is more accurate and reliable than other methods.