A compact multiband multiple-input-multiple-output (MIMO) antenna for WLAN applications is presented in this paper. The proposed MIMO antenna consists of two symmetric monopole radiating elements designed to operate over 2.45, 5.2, and 5.8 GHz bands. The isolation is enhanced by using several techniques such as parasitic elements and defected ground structure. The measured S11 < -10 dB is obtained over 2.36-2.68 GHz and 4.81-5.95 GHz, which can cover IEEE 802.11 a/b/g/n frequency bands (2.4-2.4835 GHz, 5.15-5.35 GHz, and 5.725-5.875 GHz). The measured isolation values S21 are less than -24 dB and -27 dB over the lower and higher frequency bands, respectively. The envelope correlation coefficient (ECC) of the proposed antenna is less than 0.027 and 0.005 over the lower and higher operating bands, respectively. The overall size of the proposed antenna is 50×30×1.59 mm3. The proposed antenna is a good candidate for IEEE 802.11 a/b/g/n applications.
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