INVESTIGATION OF THE POSSIBILITY OF POSITIONING AUTONOMOUS UNDERWATER VEHICLES WHEN PERFORMING DEEPWATER MISSIONS
On the basis of experiments conducted in September 2017 in the Sea of Japan, the possibility of positioning of autonomous underwater vehicles (AUV) when performing missions at depths significantly exceeding the depth of the axis of the underwater sound channel is justified. The results of experimental studies of the effect of focusing acoustic energy in the bottom layer on the shelf and the transition to the deep sea for the conditions of summer-autumn hydrology are compared with the calculated data. Experiments on the reception of broadband pulse signals were carried out at various distances from the source of navigation signals installed off the coast near Cape of Schultz. To receive signal information, a system with hydrophones distributed along the depth was used, which provides long-term recording of signals at fixed depths or during immersion. As a result of the experiments, pulse characteristics were obtained and effective sound velocities were calculated when receiving navigation signals at depths of up to 500 meters and at distances of up to 200 km, the applicability of the results to the problems of AUV positioning was shown.