The Application Of Defected Ground Structure In Quasi-Elliptic Microwave Filters

In recent years, Defected Ground Structure(_DGS) is widely used in microwave circuit and millimeter circuit . DGS can change the effective permittivity of material and distributed capacitor and distributed inductance by etching the defected pattern on the ground of microwave circuit. Quasi-elliptic response filters are widely used in mobile and satellite communication systems for small size, light weight and compact structures.But coupling space is too small in many wideband quasi-elliptic filters. Defected Ground Structure(DGS) can increase the coupling coefficient between the resonators . DGS has been employed on the ground plane in the quasi-elliptic response filters. The coupling space has been widened to implement broadband filters. A wideband micrstrip quasi-elliptic filter with DGS has been designed using 3D EM simulate on software HFSS.