A compact EBG structure loaded with capacitors and inductors in series

Based on the analysis of the equivalent circuit model for mushroom-like electromagnetic band-gap structure, a compact EBG structure is proposed. Capacitors and inductors are loaded in series between the neighboring metal patch units in this paper The research demonstrates that when the size of the unit cell remains constant, the band-gap frequency can be decreased by this loading way. Therefore, it can effectively reduce the size of the mushroom-like EBG structure. With 5.5nH inductors and 1pF capacitors loaded, the reduction of size is around 67% compared to mushroom-like EBG structure. The periods of the two EBG lattices are no more than 0.05λ at the band-gap frequency. Besides, by adjusting loading inductance, the band-gap frequency can be flexibly changed. The simulation and experimental results have proved the compactness and tunability of this structure.