臺灣博碩士論文加值系統

可見光(波長範圍350~750 nm)通訊可將全球高速網路延伸至特定空間，是未來銜接人類社會所有通訊網路的必要發展，藉由使用具有比發光二極體更高調變頻寬與更低發散角的藍光雷射二極體，不但能提高可見光通訊之傳輸速率，也能以低衰減係數有效進行水下通訊，同時若搭配黃色螢光片或混合以紅光與綠光雷射二極體，更可在通訊外添加白光照明功能。
首先，在最佳化操作參數後，所使用之藍光雷射二極體可實現10.8-Gbps/16-m之點對點自由空間傳輸性能，接著以藍光雷射二極體搭配Lu3Al5O12:Ce3+ 與 CaAlSiN3:Eu2+ 共摻雜之螢光玻璃為基礎建構白光照明可見光通訊系統。當螢光玻璃之厚度為0.85-mm時，其所產生之白光色溫、色座標與最大照度分別為7856 K、(0.29, 0.3)和1337 lux。同時，照明白光內之殘留藍光成分對人眼可能造成之危害藉由計算其曝露限制來分析。在不對人眼造成危害前提下，可達1-m/2.8-Gbps 之傳輸性能。
接著，利用藍光雷射二極體建構以自來水與純海水為傳輸介質之水下光通訊系統。在以自來水為基礎時，其不同傳輸距離所對應的最大傳輸速率分別為12.4-Gbps/1.7-m、12-Gbps/3.4-m、9.6-Gbps/6.8-m與5.2-Gbps/10.2-m，同時可得傳輸容量隨距離之衰減率為0.847 Gbps/m。接著將自來水更換為純海水，由於海水內雜質引起的散射會導致藍光光束在傳輸中功率被衰減。因此，其傳輸容量對距離之衰減率會增加至0.941 Gbps/m，同時其在不同傳輸距離下所對應的最大傳輸速率分別為7.2-Gbps/6.8-m與4-Gbps/10.2-m。
最後，利用紅、藍及綠光雷射二極體來建構室內照明與通訊系統，並提供分波多工訊號傳輸。藉由此方式產生之白光色座標、色溫與最大照度分別為(0.2928, 0.2981)、8382 K與7520 lux。為了減少藍光對人眼之傷害，光學密度為0.3之光衰減片被使用使產生白光之色座標與色溫分別被改變至(0.2938, 0.3513)與7275 K。在尚未混成白光前，其紅、藍及綠光雷射二極體輸出光在1公尺自由空間傳輸後分別展現10.8、10.4與8 Gbps之最大傳輸速率。而在混成白光後，在0.5公尺自由空間傳輸下，可達總傳輸速率為5.2 Gbps。

Since visible light (wavelength ranging from 350 to 750 nm) communication (VLC) can extend the global high-speed network to specific space, its development of connecting all communication networks in human society is necessary. Using blue laser diode (LD) with higher modulation bandwidth and lower divergence than light emitting diode (LED) can not only enhance the VLC transmission performance but also further perform underwater communication. By further adhering phosphorous glass upon blue LD or mixing the red/green/blue (RGB) LDs, white-lighting source can also be provided. In this thesis, laser diode based free-space, underwater, and white-lighting visible light communication is proposed.
Firstly, a 450-nm blue LD is used to perform 10.8-Gbps/16-m point-to-point VLC. Furthermore, the white-lighting VLC is constructed by adhering Lu3Al5O12:Ce3+ and CaAlSiN3:Eu2+ co-doped phosphorous glass upon 450-nm blue LD. The correlated color temperature (CCT), Commission International de l’Eclairage (CIE) and maximal illuminance value of white light generated by 0.85-mm phosphorous glass is 7856 K, (0.29, 0.3) and 1337 lux, respectively. In addition, the blue light damage of human eye is discussed by measuring the exposure limit. In addition, the white-lighting VLC with transmission data rate of 2.8 Gbps and free-space distance of 1 m is demonstrated without endangering human eyes.
Moreover, the blue LD is also used to demonstrate the tap and pure ocean water based underwater optical wireless communication (UOWC) systems. For the tap water based UOWC system, the maximal allowable transmission capacities with corresponding underwater distances of 12.4-Gbps/1.7-m, 12-Gbps/3.4-m, 9.6-Gbps/6.8-m and 5.2-Gbps/10.2-m are demonstrated, which exhibits a distance related decay rate on capacity of 0.847 Gbps/m. When using the pure ocean water to replace the tap water, it inside impurities induced scattering would attenuate the blue laser power during underwater transmission. Therefore, a slightly high decay rate of 0.941 Gbps/m is observed for the pure ocean water based UOWC system, which achieves 7.2 Gbps for 6.8-m and 4 Gbps for 10.2-m.
Finally, RGB LDs based indoor white-lighting communication is demonstrated for wavelength-division multiplexing (WDM) transmission. Before mixing the RGB LDs, the individual RGB LDs carried 16-QAM OFDM data exhibit maximal transmission data rate of 10.8, 10.4 and 8 Gbps at 1-m free-space transmission distance, respectively. After mixing the RGB laser light, the generated white light with CIE coordinate of (0.2928, 0.2981) and CCT of 8382 K exhibits a maximal illuminance of 7540 lux. To reduce the blue light hazard of human eyes, a filter with 0.3 optical density (OD) is adhered on the blue LD, and the CIE coordinate and CCT of RGB LDs generated white light are (0.2938, 0.3513) and 7275 K, respectively. Moreover, the indoor white-lighting WDM system reveals a total allowable transmission data rate of 5.2 Gbps with transmission distance of 0.5 m.

口試委員會審定書 #
誌謝 i
中文摘要 ii
ABSTRACT iv
CONTENTS vi
LIST OF FIGURES viii
Chapter 1 Introduction 1
1.1 History review of VLC system 1
1.2 Motivation 3
1.2.1 450-nm blue LD based VCL and UOWC communication system 3
1.2.2 RGB LDs based indoor lighting and communication system 4
1.3 Thesis Architecture 5
Chapter 2 Free-Space 16-m/10.8-Gbps Point to Point and Phosphorous Diffused 1-m/2.8-Gbps White-Lighting Visible Light Communication System Based on a 450-nm Blue Laser Diode 7
2.1 Introduction 7
2.2 Experimental Setup 8
2.3 Results and Discussions 9
2.3.1 Characterization of the blue LD and phosphorous glass generated white light 9
2.3.2 Point to point VLC system 13
2.3.3 White-lighting VLC system by adhering 450-nm blue LD upon phosphorous glass 23
2.4 Summary 27
Chapter 3 10.2-m High-speed Underwater Optical Wireless Communication with 450-nm Blue Laser Diode 30
3.1 Introduction 30
3.2 Experimental setup 30
3.3 Results and discussion 32
3.3.1 The optimization on transmission performance of 450-nm blue LD based UOWC system over a 1.7-m tap-water channel 32
3.3.2 450-nm blue LD based UOWC system with lengthening the underwater channel up to 10.2 m 37
3.3.3 450-nm blue LD based UOWC system over 6.8- and 10.2-m pure-ocean-water transmissions 43
3.4 Summary 48
Chapter 4 RGB laser diode based indoor lighting communication 50
4.1 Introduction 50
4.2 Experimental Setup 50
4.3 Results and Discussions 52
4.3.1 The characteristic of RGB LDs and white light gernerated by RGB LDs 52
4.3.2 RGB LDs based point-to-point VLC system 57
4.3.3 The RGB LDs based 5.2-Gbps/0.5-m WDM VLC system 61
4.4 Summary 66
Chapter 5 Conclusion 68
REFERENCE 70

1. T. Komine and M. Nakagawa, “Fundamental analysis for visible-light communication system using LED lights,” IEEE Trans. Consum. Electron., vol. 50, no. 1, pp. 100-107, Feb. 2004.
2.H. Elgala, R. Mesleh, and H. Haas, “Indoor optical wireless communication: potential and state-of-the-art,” IEEE Commun. Mag.., vol. 49, no. 9, pp. 56-62, Sep. 2011.
3.S. Rajagopal, R. D. Roberts, and S.-K. Lim, “IEEE 802.15.7 visible light communication: modulation schemes and dimming support,” IEEE Commun. Mag., vol. 5, no.3, pp. 72-820, Mar. 2012
4.W. Ding, F. Yang, H. Yang, J. Wang, X. Wang, X. Zhang, and J. Song, “A Hybrid Power Line and Visible Light Communication System for Indoor Hospital Applications, ” Comput. Ind., vol. 68, no. 5, pp. 170-178, Apr. 2015.
5.R. Sagotra, and R. Aggarwal, “Visible Light Communication,” Int. J. Comput. Trends Technol., vol. 4, pp. 906-910, Apr. 2013.
6.M. Akanegawa, Y. Tanaka, and M. Nakagawa, “Basic Study on Traffic Information System Using LED Traffic Lights,” IEEE Trans. Intell. Transp. Syst., vol. 2, no. 4, pp. 193-203, DEC. 2001.
7.G. Pang, k. Ho, T. Kwan and E. Yang, “Visible Light Communication for Audio Systems,” IEEE Trans. Consum. Electron., vol. 45, pp. 1112-1118, NOV. 1999.
8.Y. Tanaka, T. Komine, S. Haruyama and M. Nakagawa, “Indoor Visible Light Data Transmission System Utilizing White LED Lights,” IEICE Trans. Commun., vol. E86-B, no. 8, pp. 2440-2454, AUG. 2003.
9.H. B. C. Wook, T. Komine, S. Haruyama and M. Nakagawa, “Visible Light Communication with LED-based Traffic Lights Using 2-Dimensional Image Sensor,” IEICE Trans. Fundam. Electron., vol. E89-A, pp. 654-659, MAR. 2006.
10.J. Grubor, S. Randel, K-D. Langer and J. W. Walewski, “Broadband Information Broadcasting Using LED-Based Interior Lighting,” J. Lightwave Technol., vol. 26, pp. 3883-3892, NOV-DEC. 2008.
11.H. Elgala, R. Mesleh, and H. Haas, “Indoor Broadcasting via White LEDs and OFDM,” IEEE Trans. Consum. Electron., vol. 55, pp. 1127-1134, AUG. 2009.
12.A. H. Azhar, T.-A. Tran, H.-Y. Chen, and D O，Brien, “Gigabit/s Indoor Wireless Transmission Using MIMO-OFDM Visible-Light Communications,” IEEE Photonics Technol. Lett., vol. 25, pp. 171-174, JAN. 2013.
13.D. Tsonev, H. Chun, S. Rajbhandari, J. J. D. M. E. Gu, M. Haji, S. Watson, A. E. Kelly, G. Faulkner, M. D. Dawson, H. Haas, D. O’Brien “A 3-Gb/s Single-LED OFDM-Based Wireless VLC Link Using a Gallium Nitride μLED,” IEEE Photonics Technol. Lett., vol. 26, no. 7, pp. 637-640, APR. 2014.
14.G. Cossu, A. M. Khalid, P. Choudhury, R. Corsini, and E. Ciaramella, “3.4 Gbit/s visible optical wireless transmission based on RGB LED,” Opt. Express, vol. 20, no. 26, pp. B501-B506, Dec. 2012.
15.Y.-Q. Wang, Y.-G. Wang, N. Chi, J.-J. Yu and H.-L. Shang, “Demonstration of 575-Mb/s downlink and 225-Mb/s uplink bi-directional SCM-WDM visible light communication using RGB LED and phosphor-based LED,” Opt. Express, vol. 21, no. 1, pp. 1203-1208, Jan. 2013.
16.F. M. Wu, C. T. Lin, C. C. Wei, C. W. Chen, Z. Y. Chen, H. T. Huang, and S. Chi, “Performance comparison of OFDM signal and CAP signal over high capacity RGB-LED-based WDM visible light communication,” IEEE Photonics J., vol. 5, no. 4. Article Number 7901507, Aug. 2013.
17.R.-L. Li, Y.-Q. Wang, C.-J. Tang, Y.-G. Wang, H.-L. Shang and N. Chi, “Improving performance of 750-Mb/s visible light communication system using adaptive Nyquist windowing,” Chin. Opt. Lett., vol. 11, no. 8, pp. 080605, Aug. 2013.
18.S.-H. Chen and C.-W. Chow, “Hierarchical scheme for detecting the rotating MIMO transmission of the in-door RGB-LED visible light wireless communications using mobile-phone camera,” Opt. Commun., vol. 335, pp. 189-193, Jan. 2015.
19.PF. Luo, M. Zhang, Z. Ghassemlooy, H. Le Minh, H.-M. Tsai, X. Tang, L. C. Png, and DH. Han, “Experimental Demonstration of RGB LED-Based Optical Camera Communications,” IEEE Photonics J., vol. 7, no. 5, Article Number 7904212, Oct. 2015.
20.L. Liu, S. Zhou, and J.-H. Cui, “Prospects and problems of wireless communication for underwater sensor networks,” Wirel. Commun. Mob. Comput., vol. 8, no. 8, pp. 977-994, Oct. 2008.
21.J. Xu, M. W. Kong, A. B. Lin, Y. H. Song, X. Y. Yu, F. Z. Qu, J. Han, and N. Deng, “OFDM-based broadband underwater wireless optical communication system using a compact blue LED,” Opt. Commun., vol. 369, pp. 100-105, Jun. 2016.
22.F. Hanson and S. Radic, “High bandwidth underwater optical communication,” Appl. Optics., vol. 47, no. 2, pp. 277-283, Aug. 2008.
23.AS. Arnon, “Underwater optical wireless communication network,” Opt. Eng., vol. 49, pp. 015001, Jan. 2010.
24.M. Doniec, M. Angermann, and D. Rus, “An end-to-end signal strength model for underwater optical communications,” Wirel. Pers. Commun., vol. 38, no. 4, pp. 743-757, Oct. 2013.
25.J. S. Jaffe, “Underwater optical imaging: the past, the present, and the prospects,” Wirel. Pers. Commun., vol. 40, no. 3, pp. 683-700, Jul. 2015.
26.A. N. Z. Rashed and H. A. Sharshar, “Performance evaluation of short range underwater optical wireless communications for different ocean water types,” Wirel. Pers. Commun., vol. 72, no. 1, pp. 693-708, Feb. 2013.
27.C. Chen and X. Zhang, “Design of optical system for collimating the light of an LED uniforml,” J. Opt. Soc. Am.., vol. 31, no. 5, pp. 1118-1125, May. 2014.
28.W. Liu, Z. Xu, and L. Yang, “SIMO detection schemes for underwater optical wireless communication under turbulence,” Photonics Research, vol. 3, no. 3, pp. 48-53, Jun. 2015.
29.H. J. Son, H. S. Choi, N. H. Tran, J. H. Ha, D. H. Ji, and J. Y. Kim, “Study on underwater wireless communication system using LED,” Mod. Phys. Lett. B, vol. 29, no.7, Mar. 2015.
30.W. S. Pegau, D. Gray, and J. R. V. Zaneveld, “Absorption and attenuation of visible and near-infrared light in water: dependence on temperature and salinity,” Appl. Opt., vol. 36, no. 24, pp. 6035-6046, Aug. 1997.
31.H. Buiteveld, J. M. H. Hakvoort, and M. Donze, “The optical properties of pure water,” Ocean Optics, vol. XII, pp. 174-183, Jun. 1994.