A Modified Ground Plane Dual Band Compact Planar Antenna for Wimax Applications

This paper presents the design of a small planar antenna with triangular patch for WiMax application. A conventional ground plane has been modified to reduce the size and increasing the bandwidth as well as to cover the WiMax band. The triangular‐shaped patch is placed on top of the substrate and parasitic patch is placed at other side. By inserting a triangular patch in the coplanar ground plane, antenna is able to radiate at two resonance frequencies simultaneously. This antenna structure has been designed for covering (3.2–3.7GHz) and (5.2 to 5.8 GHz) WiMax bands. A low dielectric constant substrate with dielectric constant of 3.38 is selected to attain a compact radiating structure that also meets the challenging bandwidth requirement. The proposed antenna is fed by a 50 ohm coplanar wave guide feed. The antenna geometry has small size of 22mm x 21mm x .578mm and able to resonate on the 3.57 GHz and 5.23 GHz frequency with wide impedance bandwidth. This antenna provides the good return loss characteristics and the far field radiation pattern.These results indicates that this antenna have significant potential for WiMax applications. The simulation of designed antenna has been carried out by electromagnetic simulation software EMPIRE XCcel which is based on the powerful Finite Difference Time Domain method (FDTD).