Tri‐bandpass filter based on two stepped impedance resonators

A novel approach for dual‐ and tri‐band bandpass filters (BPF) design with independently controlled center frequencies and bandwidths was presented. On the one hand, a stepped impedance resonator (SIR) is designed to operate at the center frequencies of two bands simultaneously (dual‐band), on the other hand, two SIR s are designed to operate at the center frequencies of three bands simultaneously (tri‐band). To verify the proposed approach, a tri‐BPF has been designed and fabricated with printed circuit board technology. The measured results are in good agreement with the simulation results.