Study of the Features of Deep-Water Reception of Pulse Broadband Signal Emission from the Extended Shelf in the Sea of Japan

Abstract— The article discusses the theoretical and experimental results of studies of propagation of pulse pseudorandom signals in the Sea of Japan on an acoustic path with a length of 144.4 km with the hydrological conditions influenced by the consequences of a typhoon. The authors study the case of propagation of signals with a center frequency of 400 Hz from an extended shelf to the deep sea with reception at depths of 69, 126, 680, and 914 m. To receive signals, a drifting system was used with hydrophones distributed over a depth of up to 1000 m with possible long-term recording at fixed depths. Analysis of experimentally obtained impulse response showed that at all horizons with the same time range, a group of ray arrivals with a duration of about 0.5 s with a maximum in the center is recorded. Based on the results of the experiment, the effective propagation velocities of signals received at various depths were calculated, and conclusions were formulated on the possibility of solving problems of high-precision positioning of underwater objects for various purposes at depths of up to 1000 m and at a distance of hundreds of kilometers from control centers.