$2\times 2$ MIMO Wideband Circularly Polarized Patch Antenna Array for 5G Millimeter-Wave Systems

This research displays a new design of wideband Circular Polarized (CP) modified cut patch antenna with high execution for the fifth generation (5G) communication systems. This antenna be made up of a thin substrate with half circle truncated (HCT) square patch. The patch is truncated in two opposite corners with half circle, in addition to etched diagonal rectangular slot. Furthermore, the patch is feed by K-connector in a well-selected position, which is an important parameter to progress the antenna performance. The results from the simulator depicted that the suggested HCT patch antenna offers an ultra-wide bandwidth of impedance from 25.8 - 35.8 GHz with a 7.3 dBi gain and a 3-dB Axial Ratio (AR) of 27.6 - 30 GHz. Moreover, a 2X2 Multiple Input Multiple Output antenna is structured with a methodology that the polarization diversity of the adjacent antenna is exploited, the antenna array diagonal elements isolation is more than 31 dB and less than 28 dB between the neighboring antenna array elements. Moreover, the Envelope Correlation Coefficient (ECC) less than 0.5, and Channel Capacity Loss (CCL) lower than 0.4 in the operating frequency band with high Diversity Gain (DG) that makes it suitable for fifth generation MIMO.