Design and implementation of the transmitter and control system for underwater acoustic transponder

With the development of underwater acoustic technology, the application of underwater target detection and positioning is more and more wide spread. Used as an accurate target with parameter and location information in underwater measurement, positioning and navigation, the underwater acoustic transponder plays an indispensable role. The function of the transponder is to give out an accurate message in response by receiving a signal from mother-ship independently. To realize real-time and remote control, an acoustic transmitter and control system was designed and constructed for the underwater acoustic transponder described in this paper. A D-Class power amplifier was adopted as the main circuit for the transmitter, according to the performance requirements. The broadband and highly-efficient matching filtering was achieved by combining the attune matching and impedance characteristic of the transducer. The underwater acoustic transponder is difficult to be monitored and controlled when it works far away from the experiment platform, so a remote control system is needed. A DSP evaluation board, single-chip microcomputer and I
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C-to-USB converter were incorporated as the control circuit to monitor and feedback the working state of transmitter circuit. Either the pre-store waveform data in RAM or the calculated waveform in real-time could be selected to respond with the received signal promptly and accurately by means of remote controlling commands. Considering all these factors, an underwater acoustic transponder with small-volume, high-efficiency and low-power consumption was designed. In the lake and sea trials, the transponder worked with stability and reliability, and it meets the needs of engineering applications for the long-term. In comparison with similar products, it has advantages such as small volume, capability of parameter analysis, capability of calculating response waveform and remote control.