Recent advances in electromagnetic band gap resonator antennas

This paper presents recent advances related to electromagnetic band gap (EBG) resonator antennas (ERAs). In particular, we briefly review three new classes of ERAs (a) ERAs having extremely small footprints and superstructures with axial permittivity variation (APV), (b) ERAs with dielectric superstructures having transverse permittivity gradients (STPG), and (c) ERAs with phase-correcting structures (PCS). These classes present significant performance improvements compared to classical designs. State-of-the-art performance figures for each of these classes are presented after summarizing the key developments in this area.