Constant-k and m-Derived Composite Low Pass Filter Using Defected Ground Structure

This paper presents a design methodology of compact composite low pass filter using defected ground structure. Performance of the composite LPF using DGS is compared with the micro strip line LPF. DGS based composite LPF is much sharper than the micro strip line LPF, while the rejection bandwidth of the micro strip line based LPF is larger than the DGS based LPF. Size of DGS based LPF is 40% smaller than the micro strip line LPF.