Printed Broadband Asymmetric Dual-Loop Antenna for WLAN/WiMAX Applications

In this letter, a printed broadband asymmetric dual-loop antenna is presented for wireless communication applications in Wireless Local Area Network (WLAN) and Worldwide Interoperability for Microwave Access (WiMAX) to operate at the 2.4-GHz (2.3-2.7 GHz) band, 3-GHz (3.3-3.8 GHz) band, and 5-GHz (4.9-5.85 GHz) band. This antenna consists of two asymmetric radiated loops (there are ground-traces in each loop) and asymmetric feeding structure, making it easy to combine omnidirectional, multiband, and broad bandwidth. A prototype of the proposed antenna with 31 mm in length and 11 mm in width has been fabricated and experimentally investigated. The experimental results indicate that the S₁₁ ≤ -10 dB bandwidths achieved were 72% and 20% at 2.5 and 5 GHz, respectively. Experimental results verify the validity of theoretical work shown.