臺灣博碩士論文加值系統

行動裝置如智慧型手機朝向多功能用途之技術發展己是目前世界的潮流與趨勢，而微投影功能則是目前智慧型手機所積極想要整合的功能之一，所以在不久的未來可以預見具備微投影功能的智慧型手機將會是非常的普及。因此如能透過智慧型手機內建的微投影架構進行多功能之開發，例如結合可見光通訊技術將可以為行動裝置帶來更多及更高的附加價值。所以本論文將針對可應用於微投影架構之可見光通訊技術進行研究。由於RGB LED為目前主要的微投影光源，因此本論文首先利用RGB LED作為可見光通訊系統的發光源，進行短距離通訊系統的實現。由於應用照明用RGB LED光源於通訊傳輸有其原始調變頻寬狹窄之先天缺點，所以本論文首先透過等化器之優化設計來進行頻寬改善並嘗試透過調變技術來增加頻譜效益。次而透過光帶通濾波器之使用來探討系統分波多工之可行性。最後將此通訊傳輸技術結合微投影架構進行數據傳輸測試以驗證結合微投影架構之可見光通訊傳輸技術。從實驗結果分析得知透過後等化器的優化設計，RGB LED的三色頻寬將分別可由原始的7MHz、16MHz及14MHz改善至63MHz、76MHz及60MHz。而透過使用簡單的NRZ-OOK訊號傳輸測試可以獲得總資料傳輸率在滿足位元錯誤率(BER)為10-3 時已接近600Mb/s。而透過光帶通濾波器之使用雖然會降低每一波長之傳輸速度，但RGB LED三波長可同時提供之總資料傳輸率，仍是使用單一波長之LED無法可及。本論文最後將所實現之短距離RGB LED可見光通訊系統結合使用矽基液晶元件(LCoS)之微投影架構進行傳輸測試，量測結果顯示在僅利用單一極化光進行NRZ-OOK訊號傳輸時，已可以獲得總資料傳輸率在滿足BER值為10-3時，接進400Mb/s。

　　Since Micro-projection technology for portable communication device application (such as smart phones) has been investigated very actively recently, it is expected that high-speed visible light communication (VLC) technologies based on the light sources of micro-projector i.e. RGB-based LEDs will be integrated into the architecture of micro-projection on portable communication devices. Compared with the conventional white light LED which is composed of blue LED and phosphor limiting the available modulation bandwidth, RGB-based LEDs has the advantages of providing a higher modulation bandwidth and can potentially be used to perform a multi-channel transmission simultaneously through the use of multiple wavelengths.
　　In this research, an experimental short-range high-speed VLC link using RGB-based LEDs which has widely employed as the major light source for micro-projection application is presented. The performance of an equalized receiver with broadband optical filter used to receive multiple optical signals transmitted from RGB-based LEDs is reported. This receiver is composed of broadband optical filters and a first-order RC post-equalization circuit which was investigated to improve the RGB-based LEDs modulation bandwidth. Digital transmission test using different modulation techniques (i.e. NRZ-OOK and M-PAM) have employed to explore the data transmission rate. A proof of concept LCoS (Liquid Crystal on Silicon) device based micro-projection architecture was also applied to evaluate the transmission performance of the implemented VLC link.
　　The system performance in terms of BERs were evaluated through the eye-diagram measured from Oscilloscope. The measurement results shown that with the use of a designed 1st order RC post-equalizer in a short range VLC link, an aggregative data transmission rate nearly 600 Mb/s at a BER of 10-3 can be achieved by using NRZ-OOK modulation scheme without any offline signal processing. Finally, the digital transmission test of the implemented VLC link using NRZ-OOK modulation scheme was evaluated in a LCoS-based micro-projection architecture and the results demonstrated that an aggregative data transmission rate nearly 400 Mb/s at a BER of 10-3 can be achieved based on using only one polarization state of light.

摘要 Ⅰ
Abstract Ⅱ
誌謝 Ⅳ
目錄 Ⅴ
圖表索引 Ⅷ
第一章 緒論 1
1.1前言 4
1.2研究動機與目的 2
1.3論文架構 2
第二章 可見光通訊技術 4
2.1 微投影機技術 4
2.1.1 微投影機主要光源比較 4
2.1.2 照明系統 5
2.1.3 成像元件 6
2.2 可見光通訊系統 7
2.2.1 發射端 8
2.2.2 傳輸路徑 14
2.2.3 接收端 15
2.3 LED光通訊技術發展瓶頸 20
2.3.1 等化器 20
2.3.2 光學濾波片 22
2.3.3 調變技術 24
第三章 實驗系統的架構與特性 28
3.1 實驗設備與系統鏈結 28
3.1.1 實驗設備 28
3.1.2 實驗系統鏈結 33
3.2 實驗採用的方法 35
3.2.1 振幅調變 35
3.2.2 等化器選擇 35
3.2.3 分波多工系統 36
3.2.4 微投影架構實驗 37
3.3 調變應用與傳輸品質判定 37
3.3.1 實驗上調變之應用 38
3.3.2 傳輸品質判定 39
3.4 頻寬量測 45
3.4.1 量測方法 45
3.4.2 系統頻寬 47
第四章 等化器設計與性能改善 51
4.1 等化器原理 51
4.2 實驗之等化器 53
4.2.1 等化器介紹與性能改善 53
4.2.2 等化器設計表現 55
4.3 原始系統之傳輸速率 58
4.3.1 NRZ-OOK傳輸訊號 59
4.3.2 4-PAM傳輸訊號 62
4.4 加上等化器系統之傳輸速率 65
4.4.1 NRZ-OOK傳輸訊號 66
4.4.2 4-PAM傳輸訊號 69
4.5 本章小結 73
第五章 帶通濾波片應用與性能量測 75
5.1 濾波片介紹 75
5.1.1 濾波的方法 75
5.1.2 濾波片種類與原理 77
5.2 帶通濾波片應用 79
5.3 帶通濾波片使用前後之比較 79
5.3.1 實驗系統之傳輸速率 80
5.4 實驗結果分析 83
5.5 本章小結 84
第六章 微投影架構之應用 86
6.1 微投影應用構想 86
6.2 實驗原理與架構 87
6.2.1 偏極化分光鏡與矽基液晶的原理 87
6.2.2 應用於微投影的實驗架構 89
6.3 極化光與調變方法比較 91
6.3.1 P光與S光比較 91
6.3.2 調變方法比較 95
6.4 LCOS應用與結果 97
6.4.1 未加等化器前系統之表現 97
6.4.2 加上等化器後系統之表現 100
6.5 本章小結 102
第七章 結論與未來展望 103
7.1 結論 103
7.2 未來展望 104
參考文獻 103

[1] “Visible Light Communications Consortium.” Internet: www.vlcc.net/ , 2008.
[2] “Omega project consortium.” Internet:www.ict-omega.eu, 2008.
[3] Hoa Le Minh, Dominic O’Brien, Grahame Faulkner, Lubin Zeng, Kyungwoo Lee, Daek Wang Jung, Yunje Oh and Eun Tae Won, “100-Mb/s NRZ Visible Light Communication Using a Postequalized White LED,” IEEE PHOTONICS TECHNOLOGY LETTEERS, Vol. 21, No.15, Aug 1, 2009.
[4] L. Zeng, D. C. O’brien, H. L. Minh, G. E. Faulkner, K. Lee, D. Jung, Y. Oh, and E. T. Won, “High data rate multiple input multiple output (MIMO) optical wireless communications using white LED lighting,” IEEE J. Select. Areas Commun., vol. 27, no. 9, pp. 1654-1662, 2009.
[5] “Wireless data from every light bulb.” Internet: www.ted.com/talks/ harald_haas_wireless_data_from_every_light_bulb, Aug. 2011.
[6] G. Cossu, A. M. Khalid, P. Choudhury, R. Corsini, and E. Ciaramella,“3.4 Gbit/s visible optical wireless transmission based on RGB LED,”OSA OPTICS EXPRESS Vol. 20, No. 26, Dec 10, 2012.
[7] 簡名仁，“基於為投影架構之300Mb/s高速LED可見光通訊”，國立臺灣科技大學碩士論文，2014年六月。
[8] 陳金鑫，黃孝文，“夢幻顯示器OLED材料與元件”，五南圖書出版社，2012年2月。
[9] E.H. Stupp and M. S. Brennesholtz, Projection Display. England: Wiley, 1999.
[10] Texas Instruments. “DLP technology.” Internet: http://www.ti.com.tw/articles/detail.asp?sno=18.
[11] I. Underwood, “A review of microdisplaytechnology,” in Proc. EID, pp. 1-6, 2000.
[12] E. F. Schubert, Light-Emitting Diodes, 2nd ed., Cambridge: Cambridge University Press, 2006.
[13] 王書任，林仁鈞， “讓LED發光的功臣─螢光粉”，科學發展，第435期，第22-27頁，2009年3月。
[14] S. Muthu, F. J. Schuurmans, and M. D. Pashley, “Red, green and blue LED based white light generation: issues and control,” in Proc. IEEE IAC, pp. 327-333, 2002.
[15] K.-D.Langerand J.Grubor, “Recent developments in optical wireless communications using Infrared and visible light,” in Proc. ICTON, pp. 146-151, 2007.
[16] “Broadband Coaxial Bias Tees,” 1st ed., Picosecond Pulse Labs, Boulder, CA, 2000.
[17] Z. Ghassemlooy, W. Popoola, and S. Rajbhandra, Optical Wireless Communications: System and Channel Moderlling with MATLAB, New York: CRC Press, 2012.
[18] H. L. Minh, D. O’Brien, G. Faulkner, L. Zeng, K. Lee, D. Jung, Y. Oh, and E. T. Won, “100-Mbit/s NRZ visible light communication using a postequalized white LED,” IEEE Photonics Technol. Lett., vol. 21, no. 15, pp. 1063-1065, 2009.
[19] Hyunchae Chun, Sujan Rajbhandari, Grahame Faulkner and Dominic O’Brien, “Effectiveness of Blue-filtering in WLED based Indoor Visible Light Communication,” IEEE IWOW pp. 60-64,Sep. 17, 2014
[20] J. Grubor, O. C. G. Jamett, J. W. Walewski, S. Randel, and K.-D. Langer :High-speed wireless indoor communication via visible light, in ITG Fachbericht 198, pp. 203-208, Berlin und Offenbach: VDE-Verlag, 2007.
[21] J. Vucic, C. Kottke, S. Nerreter, K.-D. Langer, and J. W. Walewski, “513Mbit/s visible light communications links based on DMT-modulation of a white LED,” IEEE J. Lightw. Technol., vol. 28, no. 24, pp. 3512-3518, 2014.
[22] “Multipath Mitigation.” Internet: http://wshnt.kuas.edu.tw/network/s9/multipath-mitigation.htm, Apr. 2015.
[23] Y. Wang, and N. Chi, “A high-speed bi-directional visible light communication system based on RGB-LED,” China Commun., vol. 11, no. 3, pp. 40-44, 2014.
[24] J. Vucic, C. Kottke, K. Habel, and K.-D. Langer, “803 Mbit/s visible light WDM link based on DMT modulation of a single RGB LED luminary,” in Proc. OFC, pp. 1-3, 2011.
[25] 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, 2012.
[26] PDA-10A Si Amplified Fixed Detector User Guide, Thorlabs Inc., Newton, NJ, 2014.
[27] S. Haykin. Communications Systems, 4th ed., New York: John Wiley & Sons, Inc, 2001
[28] K. Szczerba, M. Karlsson, and P. Andrekson, “32.5 Gbps 8-PAM transmission over 100 m of MMF using an 850 nm VCSEL,” in Proc. ECOC, pp. 1-3, 2013.
[29] Tektronix“眼圖剖析入門手冊” Internet: http://tw.tek.com/document/1231592, 2010.
[30] D. Derickson, Fiber Optics test and Measurement, New Jersey: Prentice Hall OTR, 1998.
[31] I. Sphake, H. Takara, and S. Kawanishi, “Simple measurement of eye diagram and BER using high-speed asynchronous sampling,” IEEE J. Lightw. Technol., vol. 22, no. 5, pp. 1296-1302, May 18, 2004.
[32] 朱錫仁，電路測試技術與儀器，台北市: 儒林圖書有限公司，1992。
[33] 吳軍銳，“基於RGB LED之500 Mb/s 高速可見光通訊之研究”，國立台灣科技大學碩士論文，2014年10月。
[34] H. L. Minh, D. O’Brien, G. Faulkner, L. Zeng, K. Lee, D. Jung, Y. Oh, and E. T. Won, “100-Mbit/s NRZ visible light communication using a postequalized white LED,” IEEE Photonics Technol. Lett., vol. 21, no. 15, pp. 1063-1065, Aug. 1, 2009.
[35] Anatomy of an Eye Diagram, Tektronix Ltd., Beaverton, Ore., 2013.
[36] Himax product information, “Color-filter LCOS (CF-LCOS)” Internet: http://www.himaxdisplay.com/en/product/info.asp, 2015.
[37] “東南科技大學 電子工程系 微型投影機之光學設計研究” Internet: http://www.tnu.edu.tw/ee/upimages/file/Std-100/2006/index.htm, Dec. 2011.
[38] Michael D. Robinson, Gary Sharp, “Polarization engineering for LCD projection,” Wiley, May 2005.
[39] Jasper Display“JD4552-SP55,” Internet: http://www.jasperdisplay.com/tw/products/detail/253/, 2013.
[40] H. Li, X. Chen, B. Huang, D. Tang, and H. Chen, “High bandwidth visible light communications based on a post-equalization circuit,” IEEE Photonics Technol. Lett., vol. 26, no. 2, pp. 119-122, Jan. 15, 2014.