臺灣博碩士論文加值系統

可見光通訊系統(Visible Light Communication, VLC)是近年來快速發展之一項無線通訊技術，隨著無線通訊技術所利用頻譜資源逐漸飽和下，可見光頻段的開拓，建立在原有照明設備上且給予通訊之附加價值，為無線通訊技術注入活水。搭上現今第五代行動通訊(5G)整合物聯網(Internet of Things, IoT)趨勢，VLC勢必為重點關注技術之一，因此讓VLC傳輸品質提升便至關首要。
本論文首要探討互補式氧化物半導體(Complementary Metal-oxide Semiconductor, CMOS)影像感測器所獨有滾動式快門效應(Rolling Shutter Effect, RSE)，其形成影像機制搭配接收載入燈具之調變訊號，紀錄其二維影像轉換為一維邏輯陣列，需藉由影像增強演算法進行解調變流程，使傳輸品質穩定且有效還原原始訊號；接著介紹兩種調變格式分別應用於廣告燈箱及發光二極體(Light-emitting Diode, LED)，基於智慧性手機以及單眼相機接收，傳輸媒介多元性下，我們從較穩定方式來討論實用性，未來研究目標將可直接提升傳輸距離或是傳輸速率等傳輸品質。

Nowadays, visible light communication (VLC) has become one of the promising wireless communications, Due to the saturation of frequency bands used by traditional wireless communication technologies VLC can provide extra wireless communication channels by using the visible spectrum. Besides, VLC can provide additional values for lighting and wireless communication industries. By seizing the opportunity the fifth generation mobile communication (5G) integrated with the Internet of Things (IoT), VLC could be part of the crucial and promising issue in communication, and how to enhance the VLC transmission quality is an appealing research topic.
In this thesis, we first explored the mechanism of the rolling shutter effect (RSE), in the complementary metal-oxide semiconductor (CMOS) image sensors. The RSE images record the modulated VLC signal, and then 2-D images can be transformed into 1-D logic arrays by using off-line MATLAB® program. Demodulation algorithm is used to efficiently decode the signal and to enhance the performance. In this thesis, we also studied the VLC system using two kinds of light sources: advertisement light-box and light emitting diode (LED) lamp. The experimental results show that both systems can be applicable for practical uses.

摘要 ii
Abstract iii
誌謝 iv
目錄 v
圖目錄 vii
表目錄 xi
第一章 緒論 1
1.1 前言 1
1.2 研究動機 1
1.3 章節提要 6
第二章 CMOS影像感測器為接收端之可見光通訊系統 7
2.1 前言 7
2.2 基本實驗架構介紹 7
2.2.1 LED發射端 8
2.2.2 CCD與CMOS影像感測器之介紹 11
2.2.3 CCD與CMOS影像感測器曝光機制 14
2.3 以RSE傳輸訊號之調變 16
2.4 以RSE傳輸訊號之解調變 18
2.4.1 改善可見光源過曝現象之影像處理 19
2.4.2 利用平滑化增強亮暗對比 22
2.4.3 閥值及灰階值二值化 24
2.4.4 同步與幀間間隔 27
第三章 頻率偏移調變應用於廣告看板 30
3.1 前言 30
3.2 調變設計 30
3.2.1 FSK資料封包 31
3.3 實驗架構 33
3.4 解調變流程 37
3.5 結果與討論 39
3.5.1 單一頻率測試結果 40
3.5.2 FSK實驗結果 44
第四章 單眼相機應用於長距離傳輸之可見光通訊系統 55
4.1 前言 55
4.2 調變設計 55
4.2.1 UFSOOK資料封包 57
4.3 實驗架構 58
4.4 解調變流程 60
4.1 結果與討論 67
4.1.1 白光LED燈源結果 67
4.1.2 RGB LED燈源結果 68
第五章 結論與未來發展 71
5.1 結論 71
5.2 未來展望 72
參考文獻 73
著作列表 76

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