A novel design of half-mode substrate integrated waveguide(HMSIW) filter with SCMRC

A novel spiraled compact microstrip resonant cell (SCMRC) is proposed and applied to the design of half-mode substrate integrated waveguide (HMSIW) bandpass filter. SCMRC can lower the cutoff frequency of HMSIW while keeping the size and good transmission characteristics. The HMSIW filter with SCMRC has a passband between 3.46GHz and 3.71GHz, besides, it has both smaller size and better return loss compared with other EBG structure SIW or HMSIW filter. In this paper, such a filter is designed, manufactured and measured. Good agreement between measurement and simulation results demonstrates that the design is effective.