volume | PIER Journals

Abstract

To meet the multi-band coverage requirements of 5G smartphones, this paper presents a dual-band antenna pair with high isolation. Based on the principle of mode orthogonality, a T-shaped dual-arm antenna and a bent-loop antenna are integrated within the smartphone frame, enabling excitation of multiple in-phase and anti-phase modes across the two target frequency bands. Under closely spaced arrangement and without requiring additional decoupling structures, the antenna pair achieves superior isolation exceeding 20 dB. A multiple-input-multiple-output (MIMO) antenna array, formed by symmetrically arranging four such antenna pairs, covers the 3.4-3.6 GHz and 5.1-5.76 GHz bands. The isolation across both bands remains better than 15 dB, with efficiencies exceeding 70% and 72%, respectively. The array supports 5G n77/n78 and Wi-Fi frequency bands, and the envelope correlation coefficient (ECC) between ports is below 0.04, demonstrating favorable spatial diversity performance. The proposed MIMO antenna array features a compact form factor and excellent isolation isolation, enabling multi-antenna integration, dual-band operation, and self-decoupling within a limited volume. This design provides a technical reference for future multi-band, multi-antenna system development in 5G mobile terminals.

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Dr. Bowen Song

Professor Han Lin

Professor Zhonggen Wang

Professor Wenyan Nie