A compact bandstop resonator using broadside coupled meander line on the patterned ground structure is proposed. The broadside coupled line resonator is implemented on the patterned ground plane and is connected to the microstrip signal line using via hole. The new structure can reduce the radiation loss in the stopband by the strong coupling between microstrip signal line and broadside coupled line.

bandstop filter, patterned ground structure, higher mode suppression, notch filter, broadside coupled.