Bandwidth Extension of Ultra-wideband Microstrip Antenna Using Metamaterial Double-side Planar Periodic Geometry

A compact extended bandwidth UWB microstrip antenna is designed utilizing metamaterial (MTM) doubleside planar periodic structures. The proposed antenna comprises two MTM unit cells made by etching X-shaped slots on the main radiating patch, and four slots at the vertices of a square periodically repeated in two-dimensions on the ground plane. The proposed antenna fabricated on 1.6 mm low-cost FR4 substrate is compact, measuring 27.6 32 mm 2 , with relative permittivity of 4.5 and loss tangent of 0.02. It has a broad bandwidth covering 3.2 to 23.9 GHz, with a peak gain of 6.2 dB at 8.7 GHz. The antenna has good radiation characteristics for UWB applications. The measured return loss (S 11 ) of the test antenna fabricated for this study was in good agreement with the simulated results.