A triple band MIMO slot antenna with enhanced resonance for WiMAX, Wi-Fi and WLAN applications

A triple-band multiple input multiple output (MIMO) slot antenna with ? /4 wavelength slots of varying lengths that cover the operating frequency ranges of 1.6-1.8 GHz, 3-3.3 GHz and 4.5-4.8 GHz is presented in this paper. To achieve isolation of greater than -50 dB between the ports, a simple decoupler network is built for a large slot and a series of tapered slots. The antenna coupling is reduced by varying the ground plane. The designed antenna is fabricated using FR4 dielectric substrate with appropriate dimensions to achieve radiation across the frequency band from 1.6-4.8 GHz with more fractional bandwidth. Return loss of less than -25 dB and VSWR of 1.1 are obtained in this antenna.