The multilayer modal method for electromagnetic scattering from surfaces with several arbitrarily shaped grooves

Abstract

The problem of electtomagnetic scattering from a perfectly conducting corrugated surface having a finite number of arbitrarily shaped grooves is solved by means of the multilayer modal method. The R-matrix propagation algorithm is used to improve numerical stability for deep surfaces. Comparisons with the results obtained by the integral method are shown, among other numerical examples.

Modal method for scattering by arbitrarily shaped multivalued surfaces

“…In what follows we shall drop the superscript l to simplify the notation, as the same procedure is repeated for every groove. The propagation process is essentially the same as that used for the treatment of singlevalued surfaces [17]. The main di erence which arises from the bivalued characteristic of the pro®le is that the cavity should be divided into two single-valued parts (regions 1 and 2 (see ®gure 3)) to apply the process properly.…”

Rigorous formulation for electromagnetic plane-wave scattering from a general-shaped groove in a perfectly conducting plane: comment

“…The multilayer modal method was first proposed to deal with infinite periodic gratings [3], and since then there has been a large amount of work devoted to extend this formalism to deal with other, more complex, structures. The cases of a single groove and of a finite number of grooves on a ground plane were considered first [2,4]. In these two papers the authors already used the multilayer modal method-the same formalism proposed in [1].…”

“…The authors of [1] even state that "The developed method for the general-shaped groove is extendable to multiple general-shaped grooves (finite gratings)" [1], p. 1648. In fact, many extensions dealing with general shapes have already been done several years ago [2][3][4][5][6][7][8].…”