Influence of double interaction in multipath propagation at small grazing angles
In the case of low wind-induced waves the surface irregularities of troughs between sea waves ridges are located outside of the deep shadowing region with respect to the corresponding points and it is necessary to estimate their role in the field forming at the receiving point. The analysis has demonstrated that under these conditions there may occur a multiple interaction of the irradiating field with the irregularities of underlying surface. The analysis is limited by the account of double interaction due to the significant magnitude reduction for each reradiation of the secondary wave with respect to the original one. It this paper we propose to estimate its influence using the technique of comparison of the received signal characteristics, which have been obtained by taking into account the double interaction and without it.
The characteristics are obtained by the simulation of the electromagnetic field propagation in the case of low wind-induced waves in the context of Kirchhoff approximation using the secondary Huygens sources principle.
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