Leveraging Bellhop Model and Multi-Criteria Decision Making for Reliable Underwater Acoustic Link in Marine Buoy System

Due to its long-range capability, the underwater acoustic channel is commonly used as communication link media between the bottom and surface unit in a marine buoy system. However, changes in the sea environment heavily affect the underwater acoustic channels, making them less reliable than radio waves. This problem brings up challenge in determining the optimal distance between the bottom unit and the surface buoy. To address this problem, this paper leverages the Bellhop model to investigate acoustic channel loss characteristics for both uplink and downlink at this particular channel due to varying underwater sound speeds. Once the channel loss characteristics have been obtained, we define a mathematical formulation by using the multi-criteria decision making (MCDM) method to determine the optimal distance between the bottom and surface unit that would offer more reliable acoustic link. The results show that the proposed technique is capable of determining optimal distance for different buoy mooring configurations. We believe that the proposed method will benefit for buoy construction and deployment guideline