Rectangular circular and radial cavity resonator substrate integrated waveguide bandstop filters

A bandstop filter utilizing Substrate Integrated Waveguide cavity resonators coupled to the SIW line is presented in this paper. Prior to this research, rectangular cavity resonator was utilized to provide a bandstop response. In this paper, circular and radial cavity resonators are proposed to provide a bandstop response. The filters are designed to operate at X-band and implemented on RT/Duriod 4350 substrate with a thickness of 0.508 mm. The simulated results of the circular and radial bandstop filters have shown good bandstop responses and thus useful in microwave bandstop filter design.