Abstrakt

The possibility of using a hydroacoustic channel for digital data transmission is very limited. This is due to the effect of multipath propagation of the emitted acoustic wave and the damping of the mechanical wave in this medium, which increase with frequency. The first of these phenomena results in inter-symbol interference disturbances in data transmission systems, including even hundreds of symbols. Due to the number of reflections and, at the same time, the long memory time of the hydroacoustic channel, it is particularly difficult to ensure communication in water of harbour areas, channels and straits with a rocky bottom etc. Therefore, our goal is to develop a method of echoes reduction in the hydroacoustic channel, which could be used in broadband underwater communication systems. The article presents researches carried out on method of echo reduction in digital data transmission in the hydroacoustic channel. The effectiveness of the method will be evaluated based on a comparison of the impulse responses of the hydroacoustic channel determined before and after the elimination of the echo. Moreover the variance of in-phase component as well as coefficient of variation will be determined for transmitted digital data and compared before and after using proposed method of echoes elimination. The researches will be carried out for different carrier frequencies of the test signals. In the research, we will use simulation methods and experimental research conducted in the laboratory conditions.

Autorzy (4)