Miniatured LPF Design on a Double-Layered Defected Ground Structure

A defected ground structure (DGS) lowpass filter is designed on a double-layered substrate. By increasing the effective dielectric constant on a DGS plane, the DGS pattern can be minimized. An equivalent circuit model is presented and circuit elements are extract to design the lowpass filter. The simulated, modeled, and experimental results have been well matched to the new design method.