Improved Microstrip Circulator Design by Modified Resonance computations

Microstrip circular disc resonators with pure dielectric or gyrotropic substrates are of some practical interest in the field of MIC's. To evaluate the resonance frequencies especially of those, realized on ferrimagnetic materials, a new approach was made, giving better accuracy than the commonly used magnetic-wall-model. In this paper we present a brief summary of the theory, some numerical features and several computed resonance frequencies, which agree very well with experimental data.