A compact multiband MIMO antenna for wireless internet access application

A compact multiple-input-multiple-output (MIMO) antenna of two dual-branch monopoles is proposed. It is loaded with defective ground plane structure (DGS) to improve the isolation between two antenna elements by adding the three dumbel arms between them. Proposed antenna provides three bands which covers 2.4/5.8-GHz WLAN, 2.5/3.5/5.5-GHz WiMAX and the lower UWB band (3.1-4.8 GHz) operation with S11<; -10 dB and S21<; -18 dB. The results show that the MIMO antenna can serve as a phone antenna and it is suitable for integration within portable devices and handheld terminals with total maximum gain of 2.6 dB.