Scattering from a periodic array of apertures or plates where the conductors have arbitrary shape, thickness, and resistivity
Abstract
The scattering properties of a periodic array of conductors having any shape composed of steps along the coordinate axes and illuminated by a plane wave are obtained through a rooftop current approximation. The solution, which involves a finite dimension matrix equation, is described along with an algorithm that efficiently generates the matrix elements. Results presented for arrays of rectangular apertures and thin, rectangular plates are shown to agree closely with those obtained through standard modal approaches. Convergence with respect to the number of current elements is also explored. Because the normal component of the edge current is nonzero and continuous when thickness is present, convergence is significantly better than for zerothickness structures. At glancing incidence, however, accuracy requires a finer subsection grid to properly represent the circulating current on the sidewalls, for plates, and the Ushaped current flowing near the corner of the sidewalls, for apertures.
 Publication:

IEEE Transactions on Antennas and Propagation
 Pub Date:
 November 1986
 DOI:
 10.1109/TAP.1986.1143765
 Bibcode:
 1986ITAP...34.1356R
 Keywords:

 Antenna Arrays;
 Apertures;
 Current Distribution;
 Electric Conductors;
 Electrical Resistivity;
 Electromagnetic Scattering;
 Computer Programs;
 Floquet Theorem;
 Roofs;
 Communications and Radar