Metasurface-Inspired Circularly Polarized MIMO Antenna for 5G mmWave Applications

The letter offers metasurface-inspired multipleinput-multiple-output (MIMO) antenna with circular polarization (CP). The antenna radiating element consists of 1 x 2 array nonbianisotropic split ring resonator with an interdigital capacitance. Furthermore, a four-port MIMO antenna is designed with a 8 x 8 metasurface array (M-Array) on the ground plane. The dimensions of the proposed CP MIMO antenna are 4.6 lambda(0) x 4.6 lambda(0) x 0.128 lambda(0 )at 28 GHz. The MIMO antenna with an M-Array offers a frequency range of 30.15% [(23.8 to 32.25) GHz], isolation above 55 dB and an overlapping 3 dB axial ratio bandwidth of 14% from 26.5 GHz to 30.5 GHz with a high gain of 18.5 dBi. The proposed MIMO antenna is simplified into an equivalent circuit model. Diversity metrics ensures good diversity performance including, envelope correlation coefficient (ECC < 0.01), diversity gain (DG approximate to 10 dB), channel capacity loss (CCL < 0.1 bits/Hz), and total active reflection coefficient (TARC < -10 dB). The proposed MIMO antenna's operational range includes the mmWave band [(25 to 29.5) GHz]. It is well suited for 5G new radio smart devices due to its better performance and compatibility with 5G communication standards.