Optimizing Two Targets for Calibrating a Broadband Multibeam Sonar

The new Simrad MS70 multibeam sonar has a nominal total bandwidth of 70-120 kHz. Scientific applications of this, as in fisheries and other ecological research, require calibration. The standard-target method is suitable. Design criteria for the standard target are that this be robust and dense, with a mass of order several kilograms and with target strength in the nominal range from -35 to -30 dB. Candidate targets necessarily contain...