volume | PIER Journals

Abstract

This paper proposes a compact 8-port multiple-input multiple-output (MIMO) wideband self-decoupled antenna for 5G mobile terminal applications. Based on an orthogonal mode decoupling scheme, a combination of a loop antenna and an N-shaped antenna is utilized to achieve wideband coverage and high isolation in the N79 (4.35-5.1 GHz) band. Building on this decoupling mechanism, a 5-mm clearance is created between the ground plane and the side frame to mitigate mutual coupling between ports while optimizing impedance matching to broaden the bandwidth. Four antenna modules are symmetrically distributed on the FR4 dielectric side frames, forming a compact 8-port MIMO antenna array. The measured results show that the proposed system achieves consistent isolation better than 30 dB across the target frequency band, an envelope correlation coefficient (ECC) lower than 0.005, and a total radiation efficiency over 73% (averaging 80%). Thanks to its excellent isolation and bandwidth performance in a limited space, this scheme is a highly competitive candidate design for 5G smart terminal applications.

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Dr. Linchong Sun

Professor Han Lin

Professor Zhonggen Wang

Professor Wenyan Nie

Dr. Shunqi Liu