Circular polarized phased shift 90° MIMO array antenna for 5.8 GHz application

In this paper, a circular polarized multiple input multiple output (CP-MIMO) 2×2 array structure coupled with phased shift 90° feeding line and high gain performance are presented. The presented antenna is designed to operate in particular frequency of 5.8 GHz with circular polarization. The presented antenna combine three methods into a single antenna and excited by a two of 50 Ω coaxial probe feeds. It is a combination of MIMO system which have two port coaxial feed and each port are designed using 2×2 array structure. Each array consists of four circular radiating elements which each element constructs with 90° physical phased shift feeding line to achieve circular polarized capability. The CP-MIMO array antenna is etched on FR4 substrate with 4.7 and 1.6 mm of dielectric constant and thickness respectively.