Millimeter-Wave MIMO Array with Low Interactions Between its Antenna Elements for Fifth Generation Wireless Communication Networks
Mohammad Alibakhshikenari, Esraa Mousa Ali, Iftikhar Ud Din, Bal S. Virdee, Sadiq Ullah, Salahuddin Khan, Chan Hwang See, Takfarinas Saber, Ernesto Limiti
Abstract
Abstract This paper presents a novel, compact eight-port circular MIMO antenna system designed for millimeter-wave (mmWave) 5G communication, offering a wide impedance bandwidth and high isolation. The proposed antenna array operates over a broad measured frequency range of 25–35 GHz, achieving a 10 GHz bandwidth through a unique integration of circular and rectangular slots in the ground plane. Fabricated on a low-loss Rogers RT5880 substrate (ε r = 2.2, thickness = 0.8 mm, tanδ = 0.0009), the design demonstrates excellent performance without requiring additional decoupling structures. The antenna achieves high isolation greater than 28 dB and a peak gain of 9.65 dB at 26 GHz and 28 GHz, enabling effective operation in high-attenuation mmWave environments. Compared to prior art, the presented system supports more antenna elements within a compact footprint while maintaining low Envelope Correlation Coefficient (ECC < 0.05) and high diversity gain, making it ideal for enhanced MIMO performance. Comprehensive analysis of S-parameters, radiation patterns, surface currents, and efficiency validates its suitability for next-generation 5G mmWave applications. The combination of compact geometry, high port count, wideband coverage, and exceptional isolation constitutes the core novelty of this work.