Multi-band High Impedance Surfaces Using Progressively Magnified EBG Structures

Electromagnetic Band Gap (EBG) structures are widely used in antenna engineering, low-RCS surfaces and electronic devices. In this paper, the effect of magnifying dimensions of an EBG structure on its Bandwidth (bandgap) is explored and multi-band High Impedance Surfaces (HIS) built by the magnified EBG structures are presented. The proposed structures are applicable to UWB antennas for improving radiation performance, as well as designing low-RCS surfaces. The main idea is to achieve a multi-band HIS by combining single-band EBG structures. The advantage of this combination is achieving multi-band surfaces, while it results in multi-band surfaces with narrower bandgaps compared with the bandgaps of unit cells which construct the combined surfaces. The disadvantage is due to the parasitic effects of combining EBG structures.