Precise Target Strength Pattern Measurement in an Indoor Tank
It is very important to know the target strength (TS) pattern of fish for both an acoustic survey and a design of a quantitative echo sounder. The TS pattern is defined as a function of the tilt angle. There are two methods to measure TS pattern of fish; one is the echo trace analysis method1,2 used for in situ fish, and the other is the controlled method3,4 used for dead, stunned or anaesthetized fish. Echo trace consists of successive echoes returned from the same target. By analyzing the echo trace, the TS pattern and the speed of the target is derived.
KeywordsTilt Angle Prolate Spheroid Target Strength Envelope Signal Spheroidal Model
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