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.