ELECTROMAGNETIC BAND GAP STRUCTURES IN- CORPORATE WITH DUAL BAND MICROSTRIP AN-

A Dual band Microstrip Antenna Arrays (DbMSAA) incorporated with Mushroom Electromagnetic band Gap (MEBG) and modifled Minkowski Electromagnetic Band Gap structures to further improve its radiation characteristics is reported in this work. The two difierent types of EBG structures work like a Band Rejecter (BR), separating the branch of feed line feeding two difierent groups of patch antenna arrays operating at 2.4GHz and 5.8GHz, thus making them operate individually at their particular frequencies, simultaneously. Initially, the possibilities of having a uniform and controlled radiation patterns are quite complicated to achieve due to the single port feeding technique used and developments of grating lobes at the higher band frequency, but, through the incorporation of the EBG structures, the problems could be solved immediately. The antenna's performance is improved where the grating lobes at 5.8GHz are diminished, and the radiation patterns of the dual band antenna at both frequencies become more symmetrical with increased gain.