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In this paper, we study the influence of nonlinear waves (breaking waves) on the EM signature (in X-Band) of a sea surface (considered in this paper as a perfect conductor) observed in bistatic configuration (forward propagation). Indeed, we will start the temporal numerical analysis of the scattering coefficient σHH of breaking waves in low-grazing-angles. Then we will explain the different scattering mechanism of breaking waves. To complement the theoretical study and the different simulations, we conducted a phase of evaluation and validation of radar measurements performed in the anechoic chamber of ENSTA Bretagne.
RÉSUMÉ
Dans cet article, nous présentons une étude sur l’effet hydrodynamique (non linéaire) produit par les vagues déferlantes côtières, sur le coefficient de diffusion EM d’une surface maritime (considérée ici comme un conducteur parfait). Nous avons calculé en configuration bistatique (propagation avant) les coefficients de diffusion σHH et σVV d’une série de profils de surface océanique (différentes phases de construction d’une vague déferlante), puis avons effectué une étude sur les différents types de mécanismes de diffusions qui produisent les pics de mer (effet hydrodynamique) en propagation avant et dans la bande X. Afin de compléter l’étude théorique et les simulations réalisées, nous avons effectué une phase d’évaluation et de validation par des mesures radar réalisées dans la chambre anéchoïque de l’ENSTA Bretagne.
sea surface, hydrodynamic effect, breaking waves, exact method, EM scattering coefficients, bi-static configuration (forward propagation), X-band
MOTS-CLÉS
surface maritime, effet hydrodynamique, vague déferlante, méthode exacte, coefficients de diffusion électromagnétique, configuration bistatique (propagation avant), bande X
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