Experiment Study of Millimeter Wave Propagation Characteristics in Evaporation Duct: OTFS is Suitable for Marine Applications

The rapid expansion of marine-related industries has intensified the need for robust maritime data transmission technologies. Traditionally, high-speed millimeter wave (mmWave) systems have been deemed unsuitable for marine environments due to significant propagation path losses (PLs). This study investigates the potential of marine evaporation ducts, a natural phenomena at the air-sea interface, to enhance mmWave frequency propagation by reducing signal attenuation. To examine the large-scale propagation characteristics of mmWave frequencies in environments featuring evaporation ducts, this research employed numerical simulations using ray tracing and parabolic equation methods. Additionally, a detailed field experiment was conducted to measure the PLs for a 22 GHz frequency over a 20 km shore-to-shore, over-the-horizon link with horizontal to horizontal polarization. The findings from both the numerical simulations and field tests reveal substantial multi-path effects caused by the evaporation duct phenomenon. These results indicate the necessity for orthogonal time frequency space technology to support high-speed, low-latency marine communications at mmWave frequencies.