為了因應未來第五代(5G)行動通訊的時代，各國陸續公布優先使用的5G頻帶規劃，在6 GHz以下頻帶，主要是位於3300~5000 MHz的區間，因此，能設計寬頻MIMO天線以完整涵蓋5G頻帶是必要的，並且如何在手機的狹小空間放入多個5G MIMO天線也是一項重要的技術課題。第一個設計為寬頻5G MIMO四天線設計，單天線由環圈天線及倒F形天線組成，為混合式的天線架構，藉由饋入部及輻射部間的電容耦合間隙，可以激發四分之一波長的環圈天線模態及倒F形天線模態於3300 MHz與4800 MHz，頻帶共可以涵蓋3300~5000 MHz，並且，饋入部有一分布式電感，可以調整倒F形天線模態的頻率位置，對於環圈天線模態則不受太大影響，使得單天線尺寸可進一步縮小，結構僅佔邊框面積5 × 12 mm2，由此單天線複製排列成四天線，共佔邊框面積5 × 75 mm2，配置於手機一側邊。若是將寬頻5G MIMO天線拓展頻寬以涵蓋WLAN頻帶，即可在不增加天線數量的情況下，同時應用於行動與區域網路，因此，第二個設計為5G/WLAN MIMO雙天線設計，以第一個天線設計為基礎，透過增加一環圈天線來增加操作頻帶，共涵蓋2400~2500/3300~5000/5100~5900 MHz，單天線結構僅佔邊框面積5 × 25 mm2，配置於手機另一側邊，藉由將貢獻相同模態的輻射部錯開放置，可降低天線間的耦合影響使雙天線僅需間隔5 mm，即可達成良好的隔離度及封包相關係數。最後，結合上述的兩個設計形成MIMO六天線結構，可以達成6 × 6的5G MIMO及2 × 2的WLAN MIMO系統操作，並針對實作量測的結果及通道容量數據來驗證此天線設計的實用性。

The frequency band of 3300~5000 MHz considered in the study has recently been identified by many countries to be potentially available in the fifth-generation (5G) mobile communication below 6000 MHz. It is therefore necessary for the 5G MIMO antennas to cover the wide band of 3300~5000 MHz. There are two wide band 5G MIMO antennas presented in this thesis. The first design is a hybrid inverted-F/loop antenna, which can generate a 0.25λ inverted-F antenna resonant mode and a 0.25λ loop antenna resonant mode. The two modes are combined into a wide band to cover 3300~5000 MHz. In addition, with a wide band obtained, the antenna requires a small planar size of 5 × 12 mm2. For such four 5G antennas, its total length along the side-edge frame of the smartphone is 75 mm only. Furthermore, in order to operate in heterogeneous networks, such as the mobile network and the wireless local area network (WLAN), 5G/WLAN MIMO antennas for the second design are presented. The 5G/WLAN MIMO antennas are based on the first design. By adding an additional loop antenna resonant path to the first design, it can cover 2400~2500, 3300~5000, and 5100~5900 MHz. The 5G/WLAN MIMO antenna has a small planar size of 5 × 25 mm2 and is also disposed along the side-edge frame of the smartphone. Good envelope correlation coefficients and isolation of the two 5G/WLAN MIMO antennas is obtained by placing the antennas’ radiators which contribute different resonant modes to face each other. In this case, two 5G/WLAN MIMO antennas can be spaced by 5 mm only to achieve acceptable decoupling. Finally, the six-antenna structure composed of the above two designs is presented to provide six 5G bands and two WLAN bands. From the obtained experimental results, the proposed six-antenna structure is promising for the 6 × 6 5G MIMO and 2 × 2 WLAN MIMO operations.

論文審定書 i
致謝 ii
中文摘要 iii
英文摘要 iv
目錄 v
圖次 vii
第一章 序論 (Introduction)
1.1 研究動機 1
1.2 文獻導覽 3
1.3 論文提要 3
第二章 涵蓋3300~5000 MHz之寬頻5G MIMO四天線設計 (Wideband 5G MIMO Antennas covering 3300~5000 MHz)
2.1 天線結構及技術原理說明 6
2.2 模擬結果分析 12
2.3 心得與討論 17
第三章 涵蓋2400~2500/3300~5000/5100~5900 MHz之5G/WLAN MIMO雙天線設計 (5G/WLAN MIMO Antennas covering 2400~2500/3300~5000/5100~5900 MHz)
3.1 天線結構及技術原理說明 19
3.2 模擬結果分析 23
3.3 心得與討論 28
第四章 5G MIMO及5G/WLAN MIMO六天線實作研究 (Experimental Study of 5G MIMO and 5G/WLAN MIMO Antennas)
4.1 六天線結構 29
4.2 實作結果分析 33
4.3 心得與討論 38
第五章 結論 (Conclusions) 39
參考文獻 (References) 41
著作表 (Publication List) 43

[1] GSA. (Jun. 2017) The Future of IMT in the 3300-4200 MHz Spectrum Range. [Online]. Available: https://gsacom.com/paper/future-imt-3300-4200-mhz-frequency-range/
[2] Press Release. (Nov. 2017) 工業和信息化部發布 5G 系統在 3000-5000 MHz 頻段內的頻率使用規劃. [Online]. Available: http://www.miit.gov.cn/n1146290/n4388791/ c5906943/content.html
[3] Intelsat. (Feb. 2018) Intelsat and SES Propose Joint Use of C-band by Satellite and Terrestrial Mobile Operators in the U.S. [Online]. Available: http://www.intelsat.com/ news/press-release/intelsat-and-ses-propose-joint-use-of-c-band
[4] S. Zhang, K. Zhao, Z. Ying, and S. He, “Adaptive quad-element multi-wideband antenna array for user-effective LTE MIMO mobile terminals,” IEEE Trans. Antennas Propag., vol. 61, pp. 4275-4283, Apr. 2013.
[5] Y. L. Ban, Z. X. Chen, Z. Chen, K. Kang, and J. L.W. Li, “Decoupled closely spaced heptaband antenna array for WWAN/LTE smartphone applications,” IEEE Antennas Wireless Propag. Lett., vol. 13, pp. 31-34, 2014.
[6] K. L. Wong, Y. C. Chen, and W. Y. Li, “Four LTE low-band smartphone antennas and their 4 × 4 MIMO performance with user’s hand presence,” Microwave Opt. Technol. Lett., vol. 58, pp. 2046-2052, Sep. 2016.
[7] I. R. R. Barani and K. L. Wong, “Dual-feed U-slot antenna having low envelope correlation coefficients for the LTE MIMO operation in the metal-framed smartphone,” Microwave Opt. Technol. Lett., vol. 60, pp. 295-302, Feb. 2018.
[8] K. L. Wong and J. Y. Lu, “3.6-GHz 10-antenna array for MIMO operation in the smartphone,” Microwave Opt. Technol. Lett., vol. 5, pp. 1699-1704, Jul. 2015.
[9] Y. L. Ban, S. Yang, Z. Chen, K. Kang, and J. Li, “Decoupled planar WWAN antennas with T-shaped protruded ground for smartphone applications,” IEEE Antennas Wireless Propag. Lett., vol. 13, pp. 483-486, 2014.
[10] K. L. Wong and P. W. Lin, “Compact dual-antenna with pi-shape grounded strip for enhanced bandwidth and decreased coupling for LTE tablet computer application,” Microwave Opt. Technol. Lett., vol. 57, pp. 104-111, Jan. 2015.
[11] C. Huang and P. Chiu, “Dual-band monopole antenna with shorted parasitic element,” Electron. Lett., vol. 41, no. 21, pp. 1154-1155, 2005.
[12] A. Toktas and A. Akdagli, “Wideband MIMO antenna with enhanced isolation for LTE, WiMAX and WLAN mobile handsets,” Electron. Lett., vol. 50, no. 10, pp. 723-724, 2014.
[13] S. Zhang and G. Pedersen, “Mutual coupling reduction for UWB MIMO antennas with a wideband neutralization line,” IEEE Antennas Wireless Propag. Lett., vol. 15, pp. 166-169, 2016.
[14] K. L. Wong, J. Y. Lu, L. Y. Chen, W. Y. Li, and Y. L. Ban, “8-antenna and 16-antenna arrays using the quad-antenna linear array as a building block for the 3.5-GHz LTE MIMO operation in the smartphone,” Microwave Opt. Technol. Lett., vol. 57, pp. 174-181, Jan. 2016.
[15] K. L. Wong, C. Y. Tsai, and J. Y. Lu, “Two asymmetrically mirrored gap-coupled loop antennas as a compact building block for eight-antenna MIMO array in the future smartphone,” IEEE Trans. Antennas Propag., vol. 65, pp. 1765-1778, Apr. 2017.
[16] K. L. Wong, B. W. Lin, and W. Y. Li, “Dual-band dual inverted-F/loop antennas as a compact decoupled building block for forming eight 3.5/5.8-GHz MIMO antennas in the future smartphone,” Microwave Opt. Technol. Lett., vol. 59, pp. 2715-1721, Nov. 2017.
[17] ANSYS HFSS. (2017). [Online]. Available: http://www.ansys.com/ products/electronics/ ansys-hfss
[18] M. S. Sharawi, “Printed multi-band MIMO antenna systems and their performance metrics,” IEEE Antennas Propag. Mag., vol. 55, pp. 218-232, Oct. 2013.
[19] 盧俊諭, 國立中山大學電機系2016年碩士論文, 智慧型手機之小型化 MIMO 八天 線陣列研究, pp. 19-21.