A Multi-Band Microstrip Antenna Design for WLAN/WiMAX Applications

In order to meet the growing performance demands of modern wireless devices, a tri-band microstrip antenna was developed for WLAN and WiMAX applications. The antenna is implemented on an FR4 epoxy substrate ($\varepsilon_{r}$ $=4.4$) and features two F -shaped slots and one V -shaped slot etched into its radiating element. A defected ground structure (DGS) was introduced in the ground plane to establish three distinct resonant modes, and a coaxial -probe feed was employed for effective impedance matching. The antenna’s dimensions were optimized using 3D electromagnetic simulation software. Simulated results indicate resonances at $2.44 \mathrm{GHz}, 3.52 \mathrm{GHz}$, and 5.66 GHz, which respectively cover the WLAN band ($2.40-2.49 \mathrm{GHz}$) and the WiMAX bands ($3.46-3.58 \mathrm{GHz}$ and $5.32-5.84 \mathrm{GHz}$). Prototype measurements closely agree with simulations. Thanks to its lightweight, low -cost construction and novel structural design, this antenna is well suited for terminal equipment in WLAN/WiMAX systems.