隨著行動通信逐漸由第四代行動通信(4G)轉移至第五代行動通信(5G)，無線網路(WiFi)頻段由2.4 GHz提升至5 GHz，網路傳輸與雲端伺服器之間的傳輸負載將明顯增加。在這繁重的傳輸負載下，應建立一種高速率、長距離傳輸的系統來解決此問題。
在本篇研究論文中，提出一種基於偏振多工及鎖模注入技術建構448 Gb/s PAM4 自由空間光通訊傳輸系統，將經由寬帶放大器增強後的56-Gbps四階脈衝振福調變(PAM4)的資料分別載在四個相異波長的垂直共振腔面射型雷射(VCSEL)上，之後使用鎖模注入、偏振多工技術和一對雙合透鏡來提高整體系統的傳輸性能，鎖模注入技術能使雷射增強其頻率響應，偏振多工技術可以增強整體傳輸容量，而雙合透鏡則是能顯著提高自由空間傳輸距離。因此，我們成功展示出總資料量為448-Gbps (56-Gbps × 4 × 2)在傳輸距離為600 m的自由空間中實現了良好的誤碼率性能和清晰的PAM4眼圖。

As mobile telecommunication moves from 4G to 5G, wireless broadband access moves from 2.4 GHz WiFi to 5 GHz WiFi, the transmission loading for network transmission and cloud server connection will increase noticeably. In the state of heavy transmission loading, a high-speed data, long-distance transmission system should be built to resolve these question.
In this research paper, a 448 Gb/s four-level pulse amplitude modulation (PAM4) free-space optical (FSO) links based on polarization-multiplexing injection-locked vertical-cavity surface-emitting lasers (VCSELs) is proposed. After enhancement by a broadband amplifier, the 56-Gbps PAM4 are respectively carried at four VCSELs with different wavelengths, then injection locking technique , polarization-multiplexing scheme, and a couple of doublet lenses are used to improve the system transmission performance. Injection locking technique enable the laser to enhance its frequency response, the total transmission capacity is increased by polarization-multiplexing scheme, and the FSO distance is considerably increased by doublet lenses. Therefore, we successfully demonstrated the total transmmission capacity of 448-Gbps (56-Gbs × 4 × 2) in the FSO distance of 600 meters. Satisfactory bit error ratio (BER) performance and good PAM4 eye diagram are achieved in the system.

摘 要 i
ABSTRACT ii
誌 謝 iii
目 錄 iv
表目錄 vii
圖目錄 viii
第一章 緒論 1
1.1 研究背景 1
1.1.1 何謂通訊 1
1.1.2 光纖通訊 2
1.1.3 無線通訊 3
1.1.4 自由空間光傳輸 4
1.2 研究目的與動機 5
1.3 論文結構 6
第二章 系統元件介紹 7
2.1 半導體雷射光源 7
2.1.1 分佈式回饋雷射 7
2.1.2 垂直共振腔面射型雷射 8
2.2 光放大器 9
2.2.1 摻鉺光纖放大器 9
2.2.2 拉曼放大器 12
2.3 光被動元件 13
2.3.1 偏振控制器 13
2.3.2 光學循環器 14
2.3.3 偏振分光元件 15
2.3.4 光學相位延遲線 16
2.3.5 光纖準直器 16
2.4 可調式光衰減器 17
2.5 雙合透鏡 17
2.6 濾波器 18
2.6.1 可調式光帶通濾波器 18
2.7 光檢測器 20
2.7.1 PIN檢光二極體 21
2.8 誤差檢測器 22
2.9 數位儲存示波器 23
第三章 系統相關原理及參數介紹 24
3.1 調變原理 24
3.1.1 直接調變 24
3.1.2 外部調變 25
3.2 資料格式 26
3.2.2 歸零編碼與不歸零編碼 28
3.2.3 四階脈衝振幅調變 29
3.3 鎖模注入技術 30
3.4 偏振多工 32
3.5 FSO系統 33
3.5.1 FSO系統介紹 33
3.5.2 FSO系統原理及應用 34
3.5.3 FSO系統優劣 35
3.6 光訊號雜訊比 36
3.7 位元誤碼率 37
3.8 眼圖 37
3.8.1 眼圖分析 39
第四章 利用偏振多工鎖模注入技術所建構之448 Gb/s PAM4自由空間光通訊傳輸系統 41
4.1 文獻回顧與實驗簡介 41
4.1.1 實驗簡介 41
4.1.2 50 m/40 Gb/s 自由空間光傳輸系統 42
4.1.3 建構於VCSEL的自由空間傳輸64 Gb/s PAM4 43
4.1.4 利用偏振多工技術所建構之100 Gb/s PAM4 傳輸系統 46
4.2 實驗架構 48
4.3 實驗結果分析 50
4.3.1 雙合透鏡系統分析 51
4.3.2 大氣對FSO傳輸影響分析 53
4.3.3 雷射特性與頻率響應分析 54
4.3.4 波長分析 55
4.3.5 誤碼率與眼圖之分析 56
4-4 結語 58
第五章 結論與未來展望 59
參考文獻 61
Publication List 66
中英對照表 68

[1]M. Ivrlač and J. Nossek, “Toward a Circuit Theory of Communication,” IEEE Trans Circuits Syst I Regul Pap, vol. 57, no.7, pp. 1663-1683, 2010.
[2]The Institute of Electrical and Electronics Engineers, Inc, “Part 11: Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) Specifications,” IEEE-SA Standards Board, 2012.
[3]G. Cossu, A.M Khalid, P. Choudhury, R. Corsini, and E. Ciaramella, “Long Distance Indoor High Speed Visible Light Communication System Based on RGB LEDs,” Asia Communications and Photonics Conference (ACP), 2012.
[4]V. Jayaraman, J.C. Geske, M.H. MacDougal, T.D. Lowes, F.H. Peters, D. VanDeusen, T.C. Goodnough, S.P. Kilcoyne, and D. Welch, “High temperature 1300 nm VCSELs for single-mode fiber-optic communication,” Digest of the LEOS Summer Topical Meetings, San Diego, CA, USA, pp. 19-20, 1999.
[5]G. Liu, B. Bo, Y. Qu, L. Li, and X. Ma, “High Power Semiconductor Lasers and Their Beam Properties,” Academic Symposium on Optoelectronics and Microelectronics Technology and 10th Chinese-Russian Symposium on Laser Physics and Laser Technology OptoelectronicsTechnology (ASOT), Harbin, China, pp. 4-8, 2010.
[6]IEEE Standards 802.15.7 “Short-Range Wireless Optical Communication Using Visible Light,” IEEE Standards Association, DOI: 10.1109/IEEESTD.2011.6016195, 2012.
[7]C. L. Ying, C. H. Chang, Y. L. Houng, H. H. Lu, W. S. Tsai, and H. S. Su, “Bidirectional CATV/FTTH Transport Systems Based on a RSOA,” Conference on Lasers and Electro-Optics (CLEO), San Jose, CA, USA, pp. 16-21, 2010.
[8]K.Yelen, L. M. B. Hickey, and M. N. Zervas, “A New Design Approach for Fiber DFB Lasers With Improved Efficiency,” IEEE J Quantum Electron, vol.40, no.6, pp.711-720, 2004.
[9]M. Bass, E. W. Van Stryland, D. R. Williams, and W. L. Wolfe “Handbook of Optics: Volume II – Design,” McGraw-Hill , Inc., CH13, 2010.
[10]T. Mochii, A. Shiva, H. H. Lu, C. J. Wu, T. C. Lu, C. A. Chu, and P. C. Peng, “A Bidirectional Wireless-over-Fiber Transport System,” IEEE Photon. J., vol.7, no.6, 2015.
[11]S. Jeurink and P. M. Krummrich, “Multimode EDFA With Scalable Mode Selective Gain Control at 1480-nm Pump Wavelength,” IEEE Photon. Technol. Lett., vol. 30, no.9, pp. 849-852, 2018.
[12]J. J. D. McKendry, D. Massoubre, S. Zhang, B. R. Rae, R. P. Green, E. Gu, R. K. Henderson, A. E. Kelly, and M. D. Dawson, “Visible-Light Communications Using a CMOS-Controlled Micro-LightEmitting-Diode Array,” J. Light. Technol., vol. 30, no. 1, pp. 61-67, 2012.
[13]J. T. Leonard, E. C. Young, B. P. Yonkee, D. A. Cohen, C. Shen, T. Margalith, T. K. Ng, S. P. DenBaars, B. S. Ooi, J. S. Speck, and S. Nakamura, “Comparison of nonpolar III-nitride vertical-cavity surface-emitting lasers with tunnel junction and ITO intracavity contacts,” Proceedings of International Society for Optics and Photonics (SPIE), San Francisco, CA, USA, vol. 13, 2016.
[14]S. Namiki, K. Seo, N. Tsukiji, and S. Shikii, “Challenges of raman amplification,” Proceedings of the IEEE, vol. 94, no. 5, pp. 1024-1035, 2006.
[15]J.M. Roth, R.E. Bland, and S.I. Libby, “Large-aperture wide field of view optical circulators,” IEEE Photon. Technol. Lett., vol. 17, no.10, pp. 2128-2130, 2005.
[16]T. Liu, A.R. Zakharian, M. Fallahi, J. V. Moloney, and M. Mansuripur, “Design of a compact photonic-crystal-based polarizing beam splitter,” IEEE Photon. Technol. Lett., vol. 17, no.7, pp. 1435-1437, 2005.
[17]S. Vo, D. Fattal, W. Sorin, Z. Peng, T. Tran, M. Fiorentino, and R. Beausoleil, “Sub-wavelength grating lenses with a twist,” IEEE Photon. Technol. Lett., vol. 26, no. 13, pp. 1375-1378, 2014.
[18]C. Liberale, G. Cojoc, P. Candeloro, G. Das, F. Gentile, F. De Angelis, and E. Di Fabrizio, “Micro-optics fabrication on top of optical fibers using two-photon lithography,” IEEE Photon. Technol. Lett., vol. 22, no.7, pp. 474-476, 2010.
[19] P. Chanclou, M. Thual, J. Lostec, D. Pavy, M. Gadonna, and A. Poudoulec, “Collective microoptics on fiber ribbon for optical interconnecting devices,” J. Light. Technol., vol. 17, no.5, pp. 924-928, 1999.
[20]T. Kokubun and Y. Katsuyama, “Curing shrinkage effects of UV-curable materials on fiber loss characteristics,” J. Light. Technol., vol. 8, no.11, pp. 1654-1658, 1990.
[21]C. L. Liao, Y. F. Chang, C. L. Ho, M. C. Wu, Y. T. Hsieh, C. Y. Li, M. P. Houng, and C. F. Yang “Light-Emitting Diodes for Visible Light Communication,” The International Wireless Communications & Mobile Computing Conference (IWCMC), Dubrovnik, Croatia, pp.665-667, 2015.
[22]C. Marxer, P. Griss, and N. F. de Rooij, “A Variable Optical Attenuator Based on Silicon Micromechanics,” IEEE Photon. Technol. Lett., vol. 11, no.2, pp. 233-235, 1999.
[23]A. Arbabi, E. Arbabi, Y. Horie, S. M. Kamali, S. Han, and A. Faraon, “Aberration corrected metasurface doublet lens,” Conference on Lasers and Electro-Optics (CLEO), San Jose, CA, USA, pp.5-10, 2016.
[24]J. R. Macdonald, “Active adjustable audio band-pass filter,” Journal of the Acoustical Society of America, vol. 29, no.12, pp. 1348, 1957.
[25]A. R. Chraplyvy, R. W. Tkach, and R. M. Derosier, “Network Experiment Using an 8000 GHz Tuning Range Optical Filter,” Electron. Lett., vol. 24, no.17, pp. 1071-1072, 1988.
[26]T. M. Thompson and W. Watkins, “From Error-Correcting Codes through Sphere Packings to Simple Groups”, The Mathematical Association of America: vii, 1983.
[27]J. Y. M. Lee, “Reduction of leakage current of large-area high-resistivity silicon p-i-n photodiodes for detection at 1.06 μm,” IEEE Trans Electron Devices, vol. 28, no.4, pp. 412-416, 1981.
[28]H. H. Lu, C. Y. Li, S. J. Tzeng, H. C. Peng, and W. I. Lin, “Full-duplex radio-on-fibert ransport systems based on main and multiple side modes Injection-locked DFB laser diode,” Opt. Fiber Technol., vol. 15, pp. 251-257, 2009.
[29]S. Yoshida and K. Iwshita, “Influence of amplitude modulation induced by LD direct modulation on FM signal transmission,” IEEE Photon. Technol. Lett., vol. 2, no.12, pp. 929-931, 1990.
[30]F. Yuan, D. Che, and W. Shieh, “Receiver bandwidth effects on complex modulation and detection using directly modulated lasers,” Opt. Lett., vol. 41, no. 9, pp. 2041-2044, 2016.
[31]B. Scheers and V. L. Nir, “Pseudo-Random Binary Sequence Selection for Delay and Add Direct Sequence Spread Spectrum Modulation Scheme,” IEEE Commun. Lett., vol. 14, no. 11, pp. 1002- 1004, 2010.
[32]A. Lender, “Correlative digital communication techniques,” IEEE Transactions on Communication Technology, vol. 12, no. 4, pp. 128-135, 1964.
[33]J. Lee, M. S. Chen, and H. D. Wang, “Design and Comparison of Three 20 Gb/s BackplaneTransceivers for Duobinary, PAM4, and NRZ Data,” IEEE J Solid-State Circuits, vol, 43, no. 9, pp. 2120-2133, 2008.
[34]C. Henry, N. Olsson, and N. Dutta, “Locking range and stability of injection locked 1.54 μm InGaAsP semiconductor lasers,” IEEE J Quantum Electron, vol. 21, no.8, pp. 1152-1156, 1985.
[35]A. Kaszubowska, P. Anandarajah, and L. P. Barry, “Improved performance of a hybrid radio/fiber system using a directly modulated laser transmitter with external injection,” IEEE Photon. Technol. Lett., vol. 14, no.2, pp. 233-235, 2002.
[36]S. Rajagopal, R. D. Roberts, and S. K. Lim, “IEEE 802.15.7 VLC-modulation schemes and dimming support,” IEEE Commun Mag, vol. 50, no.3, pp.72-82, 2012.
[37]X. Zhu and J. Kahn, “Free space optical communication through atmospheric turbulence channels,” IEEE Transactions on Communications, vol. 50, no. 8, pp. 1293-1300, 2002.
[38]R. B. Ruiz, A. G. Zambrana, B. C. Vazquez, and C. C. Vazquez, “Impact of relay placement on diversity order in adaptive selective DF relay-assisted FSO communications,” Opt. Express, vol. 23, no. 3, pp.2600-2617, 2015.
[39]H. Henniger and O. Wilfert, “An introduction to free-space optical communications,” Radioengineering, vol. 19, no. 19, pp. 203-212, 2010.
[40]T. Cevik and S. Yilmaz, “An overview of visible light communication systems,” International Journal of Computer Networks & Communications (IJCNC), vol. 7, no. 6, pp. 139-150, 2015.
[41]E. Saini, R. Bhatia, and S. Prakash, “High Speed Broadband Communication System for Moving Trains using Free Space Optics,” International Conference on Computational Techniques in Information and Communication Technologies (ICCTICT), New Delhi, India, 2016.
[42]F. Forghieri, R. Tkach, and D. Favin, “Simple model of optical amplifier chains to evaluate penalties in wdm systems,” J. Light. Technol., vol. 16, no. 9, pp. 1570-1576, 1998.
[43]C.Y. Li, H.H. Lu, Y. C. Wang, Z. H. Wang, C.W. Su, Y. F. Lu, and W. S. Tsai, “An 82-m 9 Gb/s PAM4 FSO-POF-UWOC Convergent System,” IEEE Photon. J., vol.11, no. 1, 2019.
[44]W. S. Tsai, H. H. Lu, C. Y. Li, T. C. Lu, C. H. Liao, C. A. Chu, and P. C. Peng, “A 50 m/40 Gbps 680-nm VCSEL-based FSO communication,” IEEE Photon. J., vol. 8, no. 2, 2016.
[45]H. H. Lu, C.Y. Li, C. M. Ho, M. T. Cheng, X. Y. Lin, Z. Y. Yang, and H. W. Chen, “64 Gb/s PAM4 VCSEL-based FSO link,” Opt. Express, vol. 25, no. 5, pp.5749-5757, 2017.
[46]R. Rodes, M. Müeller, B. Li, J. Estaran, J. B. Jensen, T. Gruendl, M. Ortsiefer, C. Neumeyr, J. Rosskopf, K. J. Larsen, M. C. Amann, and I. T. Monroy, “High-Speed 1550 nm VCSEL Data Transmission Link Employing 25 GBd 4-PAM Modulation and Hard Decision Forward Error Correction,” J. Light. Technol., vol. 31, no. 4, pp.689-695, 2013.
[47]I. I. Kim, B. McArthur, and E. Korevaar, ‘‘Comparison of laser beam propagation at 785 nm and 1550 nm in fog and haze for optical wireless communications,’’ Proceedings of SPIE, vol. 4214, pp. 26-37, 2001.
[48]M. I. Petkovic, A. M. Cvetkovic, G. T. Djordjevic, and G. K. Karagiannidis, ‘‘Outage performance of the mixed RF/FSO relaying channel in the presence of interference,’’ Wirel. Pers. Commun., vol. 96, no. 2, pp. 2999-3014, 2017.
[49]J. Zhang, J. Wang, Y. Xu, M. Xu, F. Lu, L. Cheng, J. Yu, and G.-K. Chang, ‘‘Fiber-wireless integrated mobile backhaul network based on a hybrid millimeter-wave and free-space-optics architecture with an adaptive diversity combining technique,’’ Opt. Lett., vol. 41, no. 9, pp. 1909-1912, 2016.
[50]Y. Su and T. Sato, ‘‘A key technology for standardizing outdoor optical wireless communications,’’ ICT Express, vol. 3, no. 2, pp. 62-66, 2017.