Design of co-axial fed broadband single layer rectangular microstrip patch antenna for wireless applications

Abstract

In present work, a novel co-axial fed single layer E-shaped rectangular micro strip patch antenna with broadband behavior for wireless local area network (WLAN) and world-wide interoperability for microwave access (Wi-MAX) applications is proposed. The micro strip antenna has a planar geometry that consists of a ground, a substrate, a patch, and a feed. The basic theory about the proposed structural design, impedance matching, and the radiation characteristics are studied and analyzed using method of finite difference time domain technique. Simulation was conducted using computer simulation technology microwave studio software for optimization of antenna's properties. The proposed antenna has a frequency bandwidth of about 712 MHz (5.16-5.88 GHz) at −10 dB return loss which is sufficient to make the antenna useful for 5.2/5.8 GHz WLAN and 5.5 GHz Wi-MAX application. The WLAN standard requires the antenna to cover 5.15-5.35 GHz and 5.725-5.825 GHz frequency bands and Wi-MAX requires the antenna to cover 5.25-5.85 GHz frequency band. Maximum achievable gain over the entire frequency band is 5.5 dBi. To meet the demanding bandwidth specification, a substrate of low dielectric constant is selected to obtain a compact radiating structure. Furthermore, reflection coefficient is below −10 dB over the entire frequency band at the input of the optimized E-shaped micro strip patch antenna with 50-Ω system impedance.