Network modeling of an aperture coupling between microstrip line and patch antenna for active array applications

An analytical method based on the aperture coupling theory and the derivation of the S-parameter matrix has been developed for modeling a microstrip line coupled to a microstrip patch antenna using a circular coupling aperture. Closed-form solutions were derived for scattering parameters of the coupling circuit. Input impedance and matching condition can be calculated from the equivalent six-port network. The theoretical results agree well with the measurements. The analysis should have many applications in active array and spatial power combining systems.<
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