Parallel Coupled Wide Pass-Band Filter with Dual Square Complementary Split Ring Resonator and Defected Ground Structure

Abstract

In this work, a novel design for obtaining wider pass-band was proposed using dual-square complementary split ring resonator and squared symmetrical defected ground structure. Parallel coupling was also amalgamated which helps to achieve wider band-width. Ideally, microwave filters were designed to have high return loss, diminutive insertion loss, coordinated impedance and stable frequency selectivity to avert redundant signal interference in the spectrum. The proposed structure provides excellent selectivity of -46 dB and -28 dB at the lower and upper cut-off frequencies respectively. Defected ground structure (DGS) improved the return loss of this work and insertion loss of nearly zero dB was obtained. The prototype was designed using ANSOFT HFSS 13.0 where centre frequency was maintained at 4.97 GHz. With reference to other filter techniques, better results were obtained in terms of return loss, insertion loss, selectivity, pass-band stretch, fractional band-width and Q-factor.