Improvement of directive gain for a wire dipole with novel resonant EBG reflector

Electromagnetic band-gap (EBG) structure exhibits unique electromagnetism properties that have led to a wide-range application of electromagnetic devices. This paper presented the high-directive gain antenna consisting of a wire dipole, which is horizontally lied above the novel EBG structure. The structure of EBG would be as resonator and dipole's reflector that eliminate the surface waves at edges of reflector and the back lobe of this antenna, respectively. In addition, the near-field distribution inside gap is studied to show the different distances of gap, which influence to the resonant frequency, bandwidth, and directive gain of this antenna. Consequently, we have achieved a maximum directive gain of 9.06 dBi, which is higher than a dipole with traditional ground plane. The bandwidth for -10 dB is about 15.86% at the center frequency of 5.8 GHz. Since the proposed structure remains simple but it can provide higher directive gain and larger bandwidth covering the IEEE standard (802.11a/g), the antenna, therefore, is expected to be the low cost innovation for WLAN applications.