Generalized modeling of microstrip-fed patch antennas using an equivalent delta voltage source backed by a perfect electric wall

A fullwave spectral-domain moment method using a novel excitation mechanism of an equivalent delta voltage source backed by a perfect electric wall is proposed for the numerically efficient analysis of generalized microstrip-fed patch antennas. One of the peculiar characteristics for the proposed approach is that their input impedances can be analytically obtained from only one term of the computed complex coefficient of an half piecewise-sinusoidal basis function located at the excited position of the feed line. After simulated input impedances with different strip widths of the feed line and simulated electric current distribution on the patch surface for a simple microstrip-fed rectangular patch antenna are graphically shown, microstrip-fed patch antennas with a rectangular slot located at the central position of the rectangular patch are studied. A good agreement between the simulated and measured results is achieved at the frequency shift smaller than 1.0%.