NUMERICAL-ANALYSIS OF FINITE FREQUENCY SELECTIVE SURFACES WITH RECTANGULAR PATCHES OF VARIOUS ASPECT RATIOS

The results are presented of an analysis of finite frequency selective surfaces (FSS's) with patches of various aspect ratios, using two types of basis functions. The FSS studied consists of a two-dimensional array, finite in one dimension and infinite in the other, of perfectly electrically conducting plates in free space. The analysis uses a Green's function formulation in the spectral domain and the resulting equation is solved using the method of moments (MM). To solve this equation, acceleration techniques were used to speed the evaluation of the inner products and the computer code was optimized for speed. Results are presented for a 0.1 aspect ratio patch arranged in a square lattice using both types of basis functions. These results include the currents on the patches, the scattered power density pattern, and the average power density of the scattered power as a function of frequency. Results showing 3 dB bandwidth, resonance peak versus frequency, and scattered power versus frequency are plotted for patches with aspect ratios varying from 0.1 to 1.