The FD-TD analysis of a printed square loop antenna on a finite substrate

A square loop antenna has been analyzed under the condition that the dielectric substrate, on which the loop is printed, is of infinite extent. In this analysis an electric field integral equation has been solved using the method of moments. Based on the obtained current, the radiation characteristics have been evaluated. Needless to say, the dielectric substrate is not of infinite extent for practical applications. Therefore, the radiation characteristics for a finite substrate must be revealed. For this, we analyze the loop on the finite substrate using the FD-TD method. The effects of the finite substrate on the input impedance and radiation patterns are discussed.