Application of Pocklington´s equation to analysis of dipole frequency-selective surfaces of finite size

Pocklington´s equation is applied to arrays of linear dipoles. An integral equation for the currents induced in each dipole is derived for plane-wave illumination. The equation is solved by the method of moments. The current mode amplitudes for a 5 ¿¿ 5 array and a 20 ¿¿ 5 array are compared with those given by the standard modal analysis of an infinite periodic array using the same set of basis functions. In the latter case predicted transmission responses in the frequency range 18¿¿40 GHz link the calculations to experiment. The effect of the edge region on the induced current phasors and on the scattered fields is discussed. Near the resonance frequency for TE incidence there is a pronounced amplitude variation across the 20 ¿¿ 5 array. The analysis described in the paper is not restricted to periodic lattices.