In this paper, a new type of Defected Ground Structure (DGS) for microstrip line is proposed. Using two cells of the proposed DGS with different dimensions, the dual band-reject filter is designed and numerically investigated. Results show that there are two resonance frequency centered at 4.023 GHz and 5.124 GHz. The band-stop characteristics could be controlled by adjusting the structure parameters of each cell of the DGSs and also the distance between them. Compared to the conventional DGS, the new structure has a simple and compact shape and also its rejection characteristic is steeper around the two resonant frequencies. The proposed DGSs provide Q factor of more than 50, while attenuation is at least 34 dB at resonant frequencies.

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