Character of distortion for multifrequency pulse-coded pulse signal in the underwater sound channel is determined. The results for signal distortion in underwater communication system based on radiohydroacoustic buoys are obtained. Analysis conducted for the case of single-mode propagation excitement. The character of changes in the space-time structure of acoustic information signal due to dispersion at the different distances of propagation is established and illustrated. It is shown that when pulse propagation in the waveguide acoustic signals accumulate specific distortion similar to blurring the pulse in time and space. As a result, the delay of mean energy component increases compared with the spread pulse signal in the absence of dispersion. These effects are not taken into account when using beam acoustic approximations, which can significantly impair quality of development of underwater communication systems.
underwater communication, sonar, underwater sound channel, switching signal, multifrequency code, waveguide