Compact Bandpass Filter With Good Selectivity And Wide Stopband Using Embedded SIRs

Abstract

compact bandpass filter (BPF) with four transmission zeros (TZs) is developed using folded half-wavelength stepped impedance resonators (SIR). A feed structure is designed and analyzed firstly. Then, by embedding three half-wavelength SIRs, a BPF with good selectivity and four TZs in stopband is realized. Moreover, the filter becomes more compact by folding the SIRs. Therefore, the filter has compact size, good selectivity and stopband performance. The simulation result verifies the feasibility of the design.