Design of MIMO antenna system operating in wideband of 3300 to 6400 MHz for future 5G mobile terminal applications

Abstract

In this paper, a wideband eight‐element antenna array operating in the 5G (Fifth‐generation) NR (New Radio) frequency bands N77/N78/N79 (3300‐5000 MHz), LTE (Long Term Evolution) band 46 (5150‐5925 MHz), and EU (European Union) 5G band of 5900 to 6400 MHz for 8 × 8 MIMO (Multi‐Input Multi‐Output) operation in the future 5G mobile terminal is presented. The proposed eight antenna elements are all co‐coupled‐fed IFA (Inverted‐F antenna)/loop structure, and are divided into two same sub‐arrays which printed on the inner surface of two long frames of the mobile terminal, respectively. All the simulated and measured results present consecutive 6‐dB impedance bandwidth of 3200 to 6500 MHz, acceptable isolations (better than 12 dB), and good total efficiencies (more than 50%). Besides, the proposed wideband 8‐antenna MIMO system has also shown good MIMO performances with ECCs (envelope correlation coefficient) are all lower than 0.08, and ergodic channel capacities are all higher than 37.8 bps/Hz within the entire desired operation bands. In addition, the hand phantom effects are also investigated. The prototype of the proposed wideband eight‐element antenna array is fabricated and measured, and a quite good agreement between simulation and measurement is obtained.