Research on Passive Method of Doppler Coefficient of Underwater High Speed Moving Target

Doppler estimation is an important issue for passive positioning of flank arrays. In practical applications, Doppler compensation is an effective method to correct positioning errors caused by Doppler. To obtain the Doppler coefficient difference, this paper proposes two estimation methods: a method based on frequency domain cross-correlation (Hereinafter referred to as FDC method) and a method based on feature extraction (Hereinafter referred to as FE method). FDC method obtains the cross-correlation peak position of each subband Fourier series module of the receiving signal. FE method matches the pole position of the frequency domain waveform between different array elements and calculates the frequency shift to obtain the curve of the relationship between frequency and frequency shift. This paper comparatively analyzes the estimation error and computation amount of ambiguity function method (Hereinafter referred to as AF method), FDC method and FE method. Compared with AF method, the FDC and FE methods can achieve Doppler estimation and effectively reduce the estimation computation cost.