A printed multiband multiple input multiple output (MIMO) antenna system is proposed in this paper. The MIMO antenna system is composed of two identical antenna elements which are perpendicular to each other. The defected ground plane with two microstrip lines is introduced to suppress the coupling between the antenna elements. The proposed MIMO system operates at two separated impedance bandwidths of 770 MHz (2.09-2.86 GHz) and 890 MHz (5.05-5.94 GHz) with an overall size of 50 × 50 × 1.59 mm3. The achieved isolation at the lower and higher frequency bands is higher than 20.9 dB and 17.8 dB, respectively. The proposed MIMO antenna system is feasible to be used for time-division long-term-evolution (TD-LTE, 2300-2655 MHz) and wireless local area network 802.11 a/b/g (WLAN, 2.4-2.4835 GHz, 5.15-5.875 GHz) applications.
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