Minimized Triple-Band Eight-Element Antenna Array for 5G Metal-frame Smartphone Applications

• Published in: Micromachines (Basel) Vol. 13; no. 1; p. 136
• Main Authors: Huang, Jianlin, Chen, Zhuoni, Cai, Qibo, Loh, Tian Hong, Liu, Gui
• Format: Journal Article
• Language: English
• Published: Switzerland MDPI AG 15.01.2022; MDPI
• Subjects: 5G new radio (5G NR); Antenna arrays; Antennas; Bandwidths; metal-frame smartphone; MIMO; Radiation; Smartphones; Strip; sub-6 GHz; triple-band antenna; metal-frame smartphone; triple-band antenna; MIMO; 5G new radio (5G NR); sub-6 GHz
• ISSN: 2072-666X; 2072-666X
• DOI: 10.3390/mi13010136

A multiple-input-multiple-output (MIMO) antenna array for triple-band 5G metal-frame smartphone applications is proposed in this paper. Each single antenna element consists of an S-shaped feeding strip and an L-shaped radiation strip on the metal frame. The dimension of the antenna element is only 6.5 mm × 7 mm (0.076 λ × 0.082 λ , λ is the free-space wavelength at the frequency of 3.5 GHz). The -6 dB impedance bandwidth of the proposed eight-antenna array can cover 3.3-3.8 GHz, 4.8-5 GHz, and 5.15-5.925 GHz. The evolution design and the analysis of the optimal parameters for a single antenna element are derived to investigate the principle of the antenna. The measured total efficiency is larger than 70%. The measured isolation is better than 13 dB. The measurements of the prototype agree well with the simulation results.