A novel dumb-bell-shaped defected ground structure (DB-DGS) with embedded capacitor is presented in this paper. Compared with conventional DB-DB-DGS structure, the proposed DB-DGS exhibits many attractive characteristics including double resonance, high Q value and compact size. The equivalent lumped circuit model for the novel DGS is developed, and its parameters are extracted. Based on this new DB-DGS, a low-pass filter (LPF) using the novel DB-DGS has been constructed, which provides a more steep rejection property, a wider stopband and compact size. The proposed structure is experimentally verified through the demonstration of a low-pass filter design.
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