New compact microstrip multi-resonator with G-shaped defected ground structure

In this paper, a compact multi-resonator with a new G-shaped defected ground structure (DGS) is proposed. The equivalent circuit model for the proposed resonator is presented and the equivalent circuit parameters are extracted. The influence of the geometrical dimensions on the resonant and cut-off frequencies is investigated. The new G-shaped has a good quality factor, lower cut-off frequency (7.5 GHz) and lower attenuation pole (−30 dB) if it is compared to other DGS structures with the same size. The proposed multi-resonator is realized using single resonator. Then, an implicit G-shaped is etched inside the main G-shaped to generate another resonant and so on without any additional size. Achieving compactness and more resonant frequencies are produced by multi-implicit G-shaped structures. The proposed multi-resonator could apply for high-performance band stop filter design. The design and analysis of the proposed multi-resonator is based on numerical experimentation techniques using a commercial EM simulator. The results are in excellent agreement.