Acoustic tag

By tying the received acoustic signature to the known type of programmed signal code, the specific tagged individual is identified.

A typical Acoustic Tag consists of a piezoceramic transducer, drive/timing electronics, and a battery power source [citation needed].

In normal operation, an alternating current (AC) electrical signal generated by the drive/timing electronics is impressed across the two metalization layers.

This voltage creates stress in the material, which in turn cause the transducer to emit an acoustic signal or “ping”, which emanates outward from the surface of the tube.

The hydrophone receiver picks up the sound signal and converts it to data that researchers use to plot the resulting tag positions in three dimensions, in real-time.

At present, acoustic tags are most commonly used to monitor fish approaching diversion and guidance structures at hydropower dams.