Circularly Polarized MIMO Antenna Based on Microstrip Patch and Metasurface Structures

This paper shows a two-element multiple-input–multiple-output (MIMO) circularly polarized antenna. The proposed design achieves polarization diversity by using two conventional truncated corner square patches. Since the operating bandwidth of is extremely narrow, metasurface utilized for enhancement. In open literature, several MS-based MIMO antennas have been reported. However, these designs can achieve high isolation with wide spacing between elements. For design, configuration MS modified so that be obtained smaller element spacing. concept verified measurements on fabricated prototype. measured (BW), which an overlap −10 dB impedance and 3-dB axial ration BWs, from 5.0 to 5.6 GHz (11.3%). Across this band, always higher than 20 realized gain 4.4 dBi.