A Method of Velocity Estimation for an Underwater Moving Source in Wave-Number Domain Based on The Warping Transform

Abstract

Abstract When a single hydrophone is stationary and the underwater acoustic source is moving linearly at a constant velocity at the same depth, the phase of the received sound pressure signal in the frequency domain varies nonlinearly with time. Phase linearization can be achieved by warping transformation, so a method based on warping transformation is proposed to estimate the motion parameters of the source based on warping transformation. Firstly, the warping operators under different motion parameters are constructed and then used to resample the received sound pressure. Secondly, the corresponding wave-number spectrum is obtained by the Fourier transform of the resampled sound pressure. Finally, only when the search value of the motion parameter matches the real value, the energy magnitude of the wave-number spectrum concentrating in the concerned interval is maximum. Thus, the estimation of motion parameters is achieved. Simulation data verify the effectiveness of the method. Compared with the traditional Minimum Mean Square Error (MMSE) method, the proposed method has better performance in velocity estimation at low speeds and low frequencies.