Dual-mode dual-band bandpass filter using defected ground waveguide

A novel dual-mode dual-band bandpass filter (BPF) design using a defected ground waveguide (DGW) with independently controlled centre frequencies is presented. This BPF consists of simple microstrip feedlines and embedded DGW resonators for single substrate configuration. Defected corner cut perturbation is applied to improve out-of-band performance and operating band selectivity. This filter has been designed, fabricated and measured. Good agreement between simulation and measurement verifies the validity of this design methodology.