A Compact Dual Circularly Polarized MIMO Antenna with Controlled Slots for 5G Wireless Applications Across mm-Wave Spectrum

This work presents a two-port circularly polarized multiple inputs multiple outputs (MIMO) antenna proposed for 5G mm-wave applications. This antenna consists of four low profiles slotted compact circular microstrip patch antenna with a partial ground and parasitic element for signal exchange in 5G spectra at the mm-wave range. The antenna operates between 27.2 and 28.35 GHz. A Roger RT5880 dielectric substrate measuring a compact dimension of 45.6 × 14.7 × 0.508 mm3, is used to etch the slotted antenna. The patch's cross slots are designed to improve the targeted performance metrics including a wider bandwidth and better antenna impedance matching. At the resonance frequency of 27.7 GHz, the antenna showcases a gain of 4.43dB and an impressive return-loss of -15.6 dB. Coaxial feeding is employed for its operation. The MIMO antenna array is designed to deliver high performance with an average realized gain and radiation efficiency of 9.0 dB and 90%, respectively. It has a large bandwidth of 1.15 GHz, high gain, and directivity make it a promising candidate for 5G mm-wave GHz band applications.