A slotted multiband antenna with wide-bandwidth operation at lower band for WLAN/WiMAX applications

A compact planar slotted multiband antenna for WLAN and WiMAX applications is presented in this research. The antenna consists of a trapezoidal shaped slot as the radiating patch, and rectangular and U-shaped slots as the ground plane. These slots changes the surface current distributions of the antenna, resulting in the increase in current path length, thereby making the antenna operate at multiband. The antenna has an electrical dimension of 0.21 λ
₀
× 0.23 λ
₀
×0.01λ
₀
at a lower frequency of 2.4 GHz, and is analyzed on FR4 substrate using HFSS v.13.0 simulator. The antenna has a wide-bandwidth operation at the lower resonance with S11<;-10 dB bandwidth of about 50% (2.1-3.5 GHz). At higher resonance, antenna has narrow-bandwidth operation with S
₁₁
<;-10 dB bandwidth of about 3.3% (5.8-6 GHz). Good impedance matching and stable radiation characteristics are observed across the operational bandwidth of the proposed antenna configuration.