Design of a substrate integrated waveguide bandstop filter using dual-radial cavity resonators

Dual-radial cavity resonators are proposed to design SIW bandstop filter. The bandstop filter is designed by coupling two radial cavity resonators to the SIW line. The designed bandstop filter operates at a centre frequency of 9GHz and implemented on RT/Duriod 4350 substrate with a thickness of 0.508mm and relative permittivity of 3.66. Two single cavity resonator bandstop filters are designed first and had 3-dB FBWs of around 500MHz and attenuation of -19dB. After that, dual-cavity resonators bandstop filter is designed and had 3-dB FBWs of 525MHz and attenuation of -45dB.