High-isolation WLAN MIMO laptop computer antenna array

An isolation technique for two small-size WLAN MIMO laptop computer antennas covering the 2.4/5.2/5.8 GHz bands is presented. The WLAN MIMO antennas show measured isolation of better than 21 dB in the 2.4 GHz band and 32 dB in the 5.2/5.8 GHz bands. In addition to enhanced isolation, good antenna efficiencies of better than about 70% and 90% respectively in the 2.4 GHz and 5.2/5.8 GHz bands are obtained for the two antennas. The two antennas are of a simple structure comprising a driven strip and a shorted strip, which provides two wide operating bands to cover the 2.4 and 5.2/5.8 GHz bands. Between the two antennas, there is an isolation element formed by a protruded ground plane and a spiral open slot embedded therein. The isolation element leads to enhanced isolation and good antenna efficiencies for the antennas.