Analysis and equivalent circuit of aperture-coupled cavity-fed microstrip patch antenna

A simple but accurate equivalent circuit of an aperture-coupled cavity-fed microstrip patch antenna is developed. It consists of ideal transformers, admittance elements, and transmission lines, and the related circuit-element values are computed by applying the reciprocity theorem and complex power concept with the spectral-domain immitance approach. The antenna input impedance calculated from network theory is compared with the measured data, and their good agreement validates the simplicity and accuracy of the proposed equivalent-circuit model. Based on the proposed theory, the effect of structural parameters on the antenna characteristics is also examined. (c) 2006 Wiley Periodicals, Inc.