Modeling of a novel microstrip ring resonator for wireless applications

In this paper, we present the modeling of the microstrip ring resonator (MRR) for wireless applications. The proposed MRR is designed to operate at 5.8 GHz using a combination of two sub-wavelength (A/4) bent MRRs together with two (A/8) arms to form a half ring of A/2 in length. The combined structure is excited by an end-coupled transmission line in such a way as to center couple the two half rings. The entire structure is modeled numerically using an equivalent circuit that was derived, and hence characterized with the aid of the 2D equivalent circuit modeler. The effects of the various gap capacitances on the reflection coefficients, insertion loss, resonant frequency and bandwidth are investigated.