Abstract:The Reliable Acoustic Path (RAP) is one of the important channels for deep-sea sound propagation. It is less affected by the interface, has lower propagation loss, and can spread to longer distances, and below the critical depth, the environmental noise is lower; secondly, the reliable acoustic path effectively avoids the phenomenon of multi-path expansion, and the sound ray is dominated by direct sound with stable structure. On the basis of summarizing the physical mechanism and sound propagation advantages of the reliable sound path, the sound propagation characteristics of RAP under several different ocean parameters are compared and analyzed, and then the ray model is used to simulate and analyze the structure of the received sound ray in the RAP sound channel. The single-carrier communication performance of the RAP channel was analyzed. The simulation results show that in the RAP acoustic channel, the direct sound energy is high, the propagation loss is low, the sound ray structure is stable, the multi-path expansion is small, and it is not sensitive to environmental changes, and high signal-to-noise ratio at medium to long-range distances of around 35km; the same simulation conditions The bit error rate of the RAP area is much lower than that of the shallow reception at the same distance, and the signal-to-noise ratio of the received signal in the RAP area is about 10dB higher than that of other areas. The results of this study are of great significance for realizing cross-domain transmission of deep-sea information in the vertical direction.
