Dual-band antenna modification by using dual bad EBG structure for WLAN/WiMAX applications

Abstract

In this paper, a U-slot antenna as represent of dual-band antenna is studied. This antenna covers the WLAN/WiMAX application with a moderate gain of 4.5 dBi. The antenna excites two modes of TM10 and TM20 and consequently with excitation of high order modes surface currents of antenna substrate increase. To overcome this drawback a dual-band electromagnetic bandgap (EBG) is offered and results of EBG unit cell is matched with the U-slot antenna operation bandwidth at two bands. Finally, arrange of unite cell array and antenna for two goals is investigated. As results prove, the combining antenna with EBG cells can solve the mutual coupling effect more than 20 dB and improve gain and bandwidth of antenna for about 3.5 dBi and 1% for each frequency band, respectively.