Abstract:Under water acoustic communication is a main form of the communications in oceans, but urgent solutions are needed to overcome one intractable problem of that:how to establish remote underwater acoustic communication and ensure its reliability and stability in such unfavorable underwater acoustic channels that are random temporal, spatially variable and of multipath. This paper proposes to build up a remote underwater communication system with the utilization of underwater plasma pulse signal and fixed width temporal order coding modulation. A micro underwater acoustic pulse source based on underwater plasma is designed and tested, based on which a transmitter for pulse communication is established. Several functions for pulse communication of the device is achieved:automatic start in water, clocked dormancy system, adjustable emission frequency and the encoding and decoding of code elements. With the results of underwater experiments, the transmitter behaves well in the emission of pulse signals that are set previously, and the source level can reach 217 dB with the volume of Φ60×600 mm.