Analyzing Multipath Acoustic Channel in Deep Water Based on Surface Ducts

Underwater acoustic communication stands at the forefront of technological advancements, offering a unique and challenging frontier for researchers and engineers alike. Unlike terrestrial environments, the underwater realm presents a complex and dynamic acoustic medium that significantly impacts the transmission of signals. With applications ranging from marine exploration and surveillance to offshore communication, the need to establish reliable and efficient communication links beneath the waves has become increasingly vital. The underwater environment introduces distinctive challenges, such as multipath propagation, signal attenuation, and varying ambient noise levels. These challenges stem from the characteristics of sound waves in water, where they travel at different speeds, refract, and reflect off surfaces. Hence, this work delves into the intricate realm of multipath acoustic propagation within deep water environments, leveraging insights from the characteristics of surface duct and bottom bounce. The channel characterization has been studied by evaluating transmission losses by varying underwater environmental parameters such as: temperature, salinity, pH and depth. In addition, the effect of frequency on transmission losses due to surface duct has been evaluated. It is clear from simulation results, when compared to short range at higher frequencies, transmission losses increased by 80% as the depth increases from 1000 meters to 6000 meters.