Compact Wide Stopband Half-Mode Substrate Integrated Waveguide Bandpass Filter with Co-planar Waveguide

摘要

In this paper a quarter-wavelength co-planar (CPW) resonator based bandpass filter is proposed. The main advantage of the proposed half-mode substrate integrated waveguide (HMSIW) bandpass filter structure is its compactness and two transmission zeros for wide stopband. The design and optimization of the proposed filter is carried out using the EM simulator HFSS at the designed frequency of 3.65 GHz. In order to achieve the compactness of the proposed filter, the quasi-TEM mode of HMSIW resonator and quarter-wavelength CPW resonator both are designed on the thin substrate (0.254 mm) with $arepsilon_{r}=2.2$. Further a wide stopband characteristic is studied using higher order mode of the HMSIW to suppress its first spurious passband. Finally, the S-parameter response of the simulated and fabricated prototype is studied where the simulated and measured S-parameters are in close agreement with the corresponding simulated data.