ULTRA-WIDEBAND AND MINIATURIZATION OF THE MICROSTRIP MONOPOLE PATCH ANTENNA (MMPA) WITH MODIFIED GROUND PLANE FOR WIRELESS APPLICATIONS

In this paper, ultra-wideband and miniaturization, technique for the microstrip monopole patch antenna (MMPA) in wireless applications is presented. Ultra-wideband was achieved by using printed modified ground plane on a dielectric substrate with 50 Omega microstrip feed line. This technique allows the bandwidth of the MMPA to be ultra-wideband with satisfactory radiation properties and reduces the antenna size. The proposed antenna with modified ground plane provides an impedance bandwidth (S-11 < 10 dB) more than 5.5 GHz corresponding to 116% of fundamental resonant frequency with reduction in antenna size by 20% from original size. For further improvement in antenna characteristics, electromagnetic band-gap (EBG) structure is used. The surface wave was suppressed so the antenna bandwidth was increased to be 3-11 GHz corresponding to 170%, and the antenna size was reduced 43% of its original size. Two types of EBG are used. Holes are drilled around the patch, and embedded circular patches of the electromagnetic band gap structure with suitable dimension are used. Details of the proposed antenna design have been describe, and the typical experimental results are presented and discussed. Commercial software high frequency structure simulator (HFSS) version 11 was used for the antenna design.