A Broadband Dual-Antenna System Operating at the WLAN/WiMax Bands for Laptop Computers

In this letter, a broadband dual-antenna system working at the WLAN/WiMax bands for laptop computers is proposed. The proposed dual-antenna, printed on a uniplanar printed circuits board, is composed of two symmetric antenna elements and a decoupling structure. The antenna element consists of a feeding pad and an F-shape shorted strip. And the decoupling structure consists of a protruded ground plane and two symmetric branches. The working mechanism of the dual-antenna is analyzed based on the S-parameters and surface currents distributions. The radiation patterns, gains and efficiencies are also measured. A prototype shows that the measured -10 dB impedance bandwidth is 1.30 GHz (2.40-3.70 GHz) for the lower band and 1.41 GHz (4.48-5.89 GHz) for the higher band, with the measured mutual coupling lower than -15 dB at the both bands.