A wideband planar inverted-F MIMO antenna with high isolation is proposed in this letter. The proposed MIMO antenna consists of two back-to-back planar inverted-F antennas and a fork-shaped de-coupling stub. The two planar inverted-F antennas are merged together with a shorting strip connected to the ground plane. In order to enhance the isolation, a fork-shaped decoupling stub connected to the ground plane through shorting pins is introduced, and the impedance matching is significantly improved simulta-neously. The proposed antenna prototype is fabricated and measured, and a compact size of 28×26 mm2 makes the proposed antenna be easily integrated in a MIMO system. Measured results show that the measured bandwidth for |S11| less than -10 dB covers from 5.05 GHz to 6.23 GHz, and the measured isolation is higher than 20 dB in the whole working frequency band.
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