增強LED可見光通訊傳輸表現及應用之探討

Abstract

可見光通訊是近期快速發展的一項通訊技術。可見光通訊的重點之一是利用照明源進行通訊，如此便可賦予現有照明源附加價值，使得經濟效益增加。本論文首先將探討在低頻日光燈干擾之下，利用曼徹斯特編碼﹙Manchester encoding﹚、正交分頻多工技術﹙Orthogonal frequency-division multiplexing, OFDM﹚以及NRZI編碼等不同編碼調變方法進行LED可見光通訊傳輸，並且討論其抑制低頻雜訊干擾的原理及實驗結果；接著將提出新型Dimming-OFDM技術應用在三原色RGB LED傳輸上，以實現LED調光與信號傳輸之結合，且傳輸速度可以達到兆赫等級；最後提出未來之研究目標，希望能夠將LED可見光通訊傳輸速率提升至千兆赫之數量級。

In recent years, light emitting diodes (LEDs) are being used in various applications such as indicators, lighting display and so on. Using LED in visible light communication (VLC) has attracted much attenuation recently. In this thesis, we experimentally realized several methods to reduce noise interference in VLC, including the following: Manchester encoding, Orthogonal frequency-division multiplexing (OFDM), and non-return-to-zero inverted (NRZI) encoding. Then we propose a data transmission scheme using visible light LEDs with color and dimming control. Dimming-OFDM scheme is used for the control of dimming and color with bit rate of Mbps in RGB LED. Finally we present our future work to increase transmission data rate of Gbps in VLC.