A hydrophone array calibration method for Multibeam Echo Sounder

The side-lobe level is an important factor that determines the performance of the Multibeam Echo Sounders. In order to keep the side-lobes down, the magnitude and phase discrepancies must be compensated prior to the beamforming operation. In this paper, a calibration method of MBES's received array is proposed. This method can be implemented in room other than an open water area., and it doesn't require standard hydrophones or the high precise measurement-equipment. In the paper, a received array of MBES, whose frequency is 200 kHz, is calibrated, and the results have shown that the decreased of the side-lobe level could be as low as 9-12 dB.