Underwater communication in sea environment is very challenging due to extended multipath propagation, dispersion and fading effects. Communication system, in which noise-like signals are used as an information carrier are investigated in this study. The process of cross correlation at the receiver is used for detection of transmitted information. This feature achieves Low Probability of Detection and Low Probability of Intercept (LPD/LPI) communications. The communication signals used are also environmentally safer because of their low levels. A method has been devised based on selected set of available noise like sequences to be used with BPSK modulation, although work on this scheme to be used without any carrier is also being carried out. The probability of error in the reception of signals by such system is given as a function of signal-to-noise ratio at the input of the receiver and the size of signal constellations. Bit error rate is also evaluated for different kinds of noise sequences under the influence of both simulated and actual measured ambient noise at different SNR.
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