ELECTROMAGNETIC BAND GAP STRUCTURES INCORPORATE WITH DUAL BAND MICROSTRIP ANTENNA ARRAY

A Dual band Microstrip Antenna Arrays (DbMSAA) incorporated with Mushroom Electromagnetic band Gap (MEBG) and modified Minkowski Electromagnetic Band Gap structures to further improve its radiation characteristics is reported in this work. The two different types of EBG structures work like a Band Rejecter (BR), separating the branch of feed line feeding two different groups of patch antenna arrays operating at 2.4 GHz and 5.8 GHz, 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 5.8 GHz are diminished, and the radiation patterns of the dual band antenna at both frequencies become more symmetrical with increased gain.