Spatially uncorrelated two port MIMO DRA using phase gradient PRS for dual directional pattern diversity

Abstract

This study presents a system utilizing a cylindrical shape ceramic along with a suspended frequency selective surface (FSS), designed for multiple input multiple output (MIMO) applications with dual ports. The proposed antenna system showcases dual pattern diversity properties introducing spatially uncorrelated pattern. Key features of the structured radiator include the arrangement of cylindrical ceramic and the incorporation of an FSS. The alumina ceramic is purposefully placed on the upper part of the dielectric with a joint ground plane. These ceramics are stimulated using circular aperture. To reduce the far-field correlation, FSS with similar phase gradients are placed at the top of DRA at a certain distance. This arrangement yields two distinct radiation patterns from the two ports, ensuring a diverse radiation pattern for the antenna. The proposed technique yields significant improvements, surpassing 10 dB in isolation and achieving a 70% improvement in correlation values. The measured results validate the applicability of this antenna structure for WLAN access point applications within the 5.15-5.35 GHz frequency range.