In this paper, a communication system based on DCSK - Differential chaotic shift keying modulation, which can be used in underwater acoustic communications, is proposed. Recently, we see an increase of various communication schemes using chaotic signals, which show good results in terms of signal propagation in dense environments. In this paper, three chaotic systems have been used and compared: Logistic map, Henon map and Tent map. The influence of the seawater on the propagation of acoustic signals is analyzed in such a way that instead of white Gaussian noise, a real recording in .wav format, made in the North Sea, was used in the simulations. Simulations and modeling of the communication system were performed in MATLAB.