Abstract This study presents the design and analysis of a small, high-gain, high-isolation 4-port multiple-input multiple-output (MIMO) array antenna engineered for 5G millimeter-wave (mmWave) applications at 28 GHz. The suggested antenna array, with dimensions of 30 × 30 × 0.8 mm 3 , is optimized on a Rogers RT/Duroid 5880 substrate to provide an efficient and broadband response. Each element in the array is designed to resonate precisely at 28 GHz, achieving a remarkable return loss of −30 dB, indicating exceptional impedance matching and minimum reflection losses. The antenna has a broad impedance bandwidth of 2.2 GHz (about 7.85%), guaranteeing dependable performance throughout the designated 5G mmWave spectrum. The simulated and observed outcomes show a maximum gain of 13.50 dBi, guaranteeing robust link quality for high-data-rate transmission conditions. The antenna exhibits an isolation greater than 27 dB over the working band, underscoring its appropriateness for MIMO applications by efficiently mitigating mutual coupling effects. The key performance parameters, including the envelope correlation coefficient (ECC < 0.005) and diversity gain (nearing 10 dB), validate the antenna’s efficacy for multi-antenna systems. This work introduces a novel MIMO antenna solution characterized by small dimensions, high gain, low mutual coupling, and extensive operating bandwidth, successfully fulfilling the rigorous requirements of next-generation 5G mmWave communication systems.
J et al. (Fri,) studied this question.