Radar wave propagation in an inhomogeneous evaporation duct

The propagation of radar electromagnetic waves above the sea surface is dependent upon the atmospheric conditions. Inversions in the temperature and humidity profiles above the sea are responsible for the creation of various types of duct layers. In such duct layers the EM wave propagation can be regarded as a waveguide. Special interest is given to cases where the (modified) refractive index profile correspond to duct layers of 10-40 m height known as the evaporation duct. A solution is presented for slow variations corresponding to an inhomogeneous behaviour of the atmospheric conditions as a function of the distance.<
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