Controllable dual-mode dual-passband filter using inductive short stub SRR (ISSSRR)

A novel controllable dual-band bandpass filter (BPF) with excellent band-to-band rejection is presented in this paper. The dual band filter consists of a dual split ring resonator having splits on opposite sides with inductive short stub split ring resonator (ISSSRR). Even and odd mode analysis has been performed to calculate the resonance frequencies. Three transmission zeros(TZs) are achieved between two passbands by both electric or magnetic dominant coupling and also cancellation effect of electric and magnetic coupling, resulting in high passband selectivity and improved band-to-band isolation. The proposed dual band pass filter has the advantages of being compact with more degree of freedom to achieve desired pass bands by controlling the electric and magnetic coupling. The proposed BPF achieved insertion loss of 0.5 dB and 0.8 dB at 3.35 and 5.75 GHz, respectively.