Underwater acoustic communication is a rapidly growing field of research and applied engineering. It is especially necessary for submarine-ship, submarine-submarine and ship-submarine communications. Recent years have seen rapid advances in DSP (Digital signal processor) architecture technologies, which advances have made it possible for DSP's to be used for applications previously considered unsuitable such as underwater communication. Underwater acoustic communication applications had been performed in an analog environment several times before; however, in this work, it is performed digitally by using DSP. Alternative solutions for underwater communication are presented as well. The presented solution is a more reliable prototype design of underwater acoustic communication that was developed via the transmitter and receiver sides on two identical DSK (DSP Starter Kit) boards by using upper sideband - suppressed carrier (SSB - SC) and random carrier frequencies (8 kHz - 16 kHz).