Simplified analysis of aperture coupled microstrip antenna fed by dielectric image line

The paper presents a simplified analysis of aperture coupled microstrip antenna fed by a dielectric image line. The cavity model is used to represent the fields in the microstrip antenna. The dielectric image line is assumed to be propagating only the fundamental mode. The magnetic current source due to the electric field in the aperture is assumed to be a half-sine wave. The image line is terminated by a matched load. The total impedance of the antenna and the matched load seen at the reference plane in the image line is calculated and validated with experimental results.