A Propagation Model for Rough Sea Surface Conditions using the Parabolic Equation with the Shadowing Effect
Keywords:
Electromagnetic propagation, parabolic equation, rough sea surface reflection, shadowing effect, tropospheric ductAbstract
In this article, an accurate and fast approach is proposed to calculate the electromagnetic wave propagation characteristics over the sea surface under tropospheric ducting conditions. The method is based on the parabolic equation and an asymptotic model of a rough sea surface and is used to calculate the electromagnetic characteristics and to model the sea surface reflection. In the proposed model, termed the extremum approximation of the shadowing effect (EA of SE) model, the shadowing effect is considered and simplified to improve the accuracy and shorten the computation time. The probability density functions and the propagation factors of different models are compared, the influence of the rough sea surface and the shadowing effect on the electromagnetic wave propagation is analyzed and the model accuracy and efficiency are evaluated. Some comparisons are made with experimental data. The results show that the average error is about 1 dB less after the shadowing effect is considered; and the proposed approach shortens the computation time about 600 times while maintaining a high accuracy.
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