Shape Perturbed Tunable Planar RF Resonator for the Dielectric Measurement in wide frequency range

A novel attractive methodology to realize tunable complementary split ring resonator (CSRR) based planar RF resonant structure is proposed in this work. The tunability is achieved using the shape perturbation of CSRR which actually facilitates the dynamically controlled resonant frequency over relatively wider frequency range as compared to the conventional complex biasing network based tunable designs. For facilitating the tuning, the electrical size of the multi arm CSRR (MACSRR) structure, etched in the ground plane is varied by applying a thin metallic tape over the required arms. The proposed shape perturbed CSRR based resonator yields higher operating bandwidth (67%) as compared to the earlier reported sensitivity (33%) of the electrically tuned resonator. This resonator has the sensing potential for the determination of dielectric properties over a wide frequency range.