Effects of Frequency Selective Surface (FSS) on Enhancing the Radiation Efficiency of Metal-Surface Mounted Dipole Antenna

Dipole antennas have very low radiation efficiency when they are horizontally placed above flat metal surfaces. Frequency selective surfaces (FSS) possess special electromagnetic band gap (EBG) properties, which could be utilized to improve radiation efficiency of metal-surface mounted dipole antenna. However, complex interactions between a FSS and antenna make a successful design difficult. Previous design approaches are based on the reflection phase property of FSS, which are not accurate since the reflection phase doesn´t account for the complex near field interaction. In this paper, a novel design approach based on transmission characteristics of transverse magnetic (TM) and transverse electric (TE) surface wave across the FSS is presented. The new design methods are experimentally verified with a two-port network analyzer.