Tri-band rectangle-loaded monopole antenna with inverted-l slot for WLAN/WiMAX applications

A novel coplanar waveguide-fed tri-band monopole antenna with a compact radiator (10 × 23 mm²) for WLAN/WiMAX applications is presented. By etching properly an inverted-L slot on the straight strip loaded with a rectangular tuning patch and further adjusting the dimensions and positions of these structures, three distinct wide bands can be achieved. The measured and simulated results show that the proposed antenna has 10 dB impedance bandwidth of 470 MHz (2.38-2.85 GHz), 360 MHz (3.36-3.72 GHz) and 890 MHz (4.98-5.87 GHz) to cover all the 2.4/5.2/5.8 GHz WLAN bands and 2.5/3.5/5.5 GHz WiMAX bands. Also, the proposed antenna produces good dipole-like radiation pattern over the covering bands.