Calibration Method Simulation of Linear-array Hydrophone in Underwater Acoustic Network

Abstract

Aiming at the problem that the amplitude and phase consistency of linear-array hydrophones in underwater acoustic network is difficult to calibrate accurately, this paper proposes a straightforward, high-accuracy calibration method for amplitude and phase of linear hydrophones arrays. First, the hydrophone array is submerged vertically far field of the transmitting transducer, and then the hydrophone array is lifted by a mechanical lifting device without horizontal movement during lifting. Each hydrophone receives and records the signals when it is at the same depth as the transmitting transducer. All the signals received are intercepted and proposed by Fourier transformation to obtain the amplitude-frequency and phase-frequency characteristic curves. Amplitude and phase values corresponding to a given frequency can be determined from these curves. This paper also analyzes the feasibility of the method and several factors which may cause measurement error during simulation. Finally, the calibration of the linear-array hydrophones in underwater acoustic network with ten elements is performed in the laboratory tank. Its results show that the method is effective in calibrating hydrophones for amplitude and phase and easier to operate than any other methods.