A Miniaturized MIMO Antenna with Band-Notched Characteristic for UWB Applications

This work presents a miniaturized multiple-input multiple-output (MIMO) antenna for ultrawideband (UWB) applications with band-notched characteristic. The MIMO antenna prototype presents a compact size of 18 mm x 32 mm and a high isolation above 16 dB is achieved between the antenna elements over entire UWB band. F-shaped stubs are introduced in the ground plane to improve isolation between the radiating elements. Double L-shaped parasitic element is introduced between the antenna ports to improve isolation and enhance the antenna bandwidth. Furthermore, Z-shaped slits were etched on the MIMO antenna patches to generate a band notch at the WLAN band (5.15 to 5.825 GHz). Simulations were performed in Ansoft HFSS software, for numerical characterization, and the prototype was fabricated and measured, presenting a good agreement between simulated and measured results. Moreover, the envelope correlation coefficient (ECC), which is a key performance parameter in MIMO antennas, is investigated and presents good results.