E-Plane dual band bandstop waveguide filter for possible X-band applications

Abstract

ABSTRACTThis paper presents, a novel second order E-plane planar insert based dual band bandstop waveguide filter. The circular shape with two T-shape resonators are printed on Roger RO4350 dielectric substrate to form planar insert. The insert are placed in such a way that positioned in E-plane of the standard WR-90 rectangular waveguide. The independent resonant frequency and bandwidth of the stopband can be adjusted by tuning the resonators. To achieve second order dual band bandstop filter response four asymmetrical circular shape with two T-shape resonators are designed on dielectric substrate to form different stopbands and separated by some specific distance to eliminate the unwanted coupling between them. The numerical analysis of the proposed filter is carried out using CST microwave studio. To validate the numerical analysis of the proposed filter, resonator, WR-90 rectangular waveguide is fabricated and measured. The measured results shows stopband characteristics having centre frequencies f01g = 8.56 GHz and f02 = 11.21 GHz and exhibits the bandwidth of 0.4146 GHz and 0.3824 GHz. The simulated and measured result are in good agreement.