The implementation of PC-based instrumentation for underwater acoustic communication system

This paper presents the recent progress of implementing an underwater acoustic communication system at NCKU, Taiwan. This system is realized by integrating the PC-based instrumentation, which includes a system controller, an arbitrary waveform generator, a power amplifier, and an acoustic projector (hydrophone). We have developed a command software interface using less than 5kHz bandwidth and acting as a modulator. The real time communication data in symbols can be transmitted through the water channel with the software modulator. Signal acquisition is performed at the receiver end by a hydrophone, a signal amp, the AD/DA converter, and a embedded PC. The communication signal is synchronized and demodulated using FFT analysis. The entire system is compact in size and robust in hardware, and can also be easily transformed into a digital underwater acoustic data acquisition unit for various application purposes, such as academic demonstration and fundamental research.