A CDMA acoustic communication system for multiple underwater robots

In this paper, a kind of underwater acoustic communication system based on CDMA (code division multiple access) for multiple underwater robots is proposed. This system enables multiple underwater robots to communicate with the console on the surface of water simultaneously successfully. The whole communication process is composed of channel encoding and decoding, spread spectrum modulation and demodulation, RF (radio frequency) modulation and demodulation. The effect of underwater channel on the quality of communication is also taken into account. The simulation results indicate that it is feasible to use this system to accomplish communication underwater reliably due to the small BER (bit error ratio).