Improved Coupled Markov Chain for Three-Dimensional Spatial Modelling of Inhomogeneous Evaporation Duct

As the atmospheric environment in different oceanic regions is inhomogeneous, this inhomogeneous property has an important impact on radar detection systems and mobile communication systems. However, for inhomogeneous evaporation duct data within the range of low altitude regions at sea are limited, the traditional Markov process is difficult to achieve accurate modelling of inhomogeneous evaporation duct in full space, and the traditional radar sea clutter inversion of inhomogeneous profiles is not able to achieve the inversion of inhomogeneous evaporation duct profiles in full space. Therefore, this paper firstly proposes an improved coupled Markov chain to achieve full-space modelling of inhomogeneous evaporation ducts. Tropospheric evaporation duct have different classes and corresponding spatial structural features. In this paper, we will provide a comprehensive introduction to evaporation duct in terms of their characteristics and classification, formation mechanism, etc., followed by an introduction to the parabolic equation model commonly used in the study of radio wave propagation problems. The experimental results show that our proposed improved coupled Markov chain takes into account the effect of the spatial transformation of the evaporation duct on the spatial modelling, can able to model the whole space based on the limited observations of the evaporation duct, and reduces the evaporation duct altitude errors by 1.5 m and 3.3 m compared to those of the two-dimensional Markov chain and linear interpolation methods.