Multiple Antenna System for Mobile Handset Applications

A multiple antenna system for mobile handset application is proposed. The proposed multiple antenna system consists of planar inverted-F antenna (PIFA) for mobile operation and a shorted monopole MIMO antenna with a decoupling network for WLAN operation. By adding a lambda/4 open stub to PIFA, an additional resonance at 2 GHz band was generated and consequently the impedance matching characteristic was improved. In order to improve the isolation characteristic between the PIFA and MIMO antenna elements, each element is placed at the corner of each edge of the system ground. In addition, decoupling network was added at the feeding line of a shorted monopole antenna element. The proposed WLAN MIMO antenna has the isolations of about 15 dB at 2 GHz and 5.8 GHz bands while that at 5.2 GHz band is over 18 dB. It is observed that the antenna can cover GSM/DCS/PCS/UMTS and 2.4/5.2/5.8 GHz WLAN service, simultaneously.)