- 學位論文
利用可調光發光二極體於室內可見光通訊之研究
Study on Indoor Visible Light Communication by Using Dimmable LED
摘要
可見光通訊目前已很許多研究，在室內的可見光通訊已經有研究模擬出可行性，本文對發光二極體(LED)安裝位置的方式進行研究模擬，LED陣列光源的布局研究，除了同時要滿足照明和通信需求之外，更需進一步優化室內照明和可見光通信。本文利用LED燈位置布局提高整體均勻性，達到改善各個角落傳輸速率的穩定性，同時符合室內所需照度之標準。此方法相較於之前文獻提高了7%照度均勻度，信噪比的標準差也減少了0.2dB。本文以16盞LED分布於5*5[m2]室內天花板中，可提高整體的均勻度，進而模擬其照度、接收光功率、增加漫反射後的接收光功率以及增加漫反射後的信噪比，因此室內的可見光通訊品質能有所提升，且更為穩定。 為了因應節能減碳以及綠色能源概念，本文將調降LED燈的輸出光功率，模擬降低光功率後的照度、接收光功率以及信噪比，以五種模式做模擬，在假設最佳照度以及通訊的狀態下可節省41.8%的光功率，此時的信噪比最高可提升至18.9dB，當非工作區域LED燈關閉時，最高可節省75%的輸出光功率，同時可降低接收端的雜訊，而整體的信噪比最高可提升至27.9dB，當信噪比提高時傳輸速率也能夠提升至100M/s以上。
並列摘要
There are already a lot of visible light communication research. Research has demonstrated that indoor visible light communication is feasible. This paper studies on a LED light distribution scheme first. The purposes of studying the LED array light, locations are not only to meet the lighting and communication needs, but also to optimize indoor lighting and visible light communications. Using the proposed LED lights distribution scheme is able to enhance the overall uniformity of the transmission rate, as well as meets the requirement of indoor illumination. The proposed scheme increases the 7% illumination uniformity and reduces 0.2dB standard deviation of signal to noise ratio (SNR) in the designated indoor environment. In this paper use 16 LED distributed in 5*5 [m2] ceiling of a room, it can improve the overall uniformity. In order to achieve carbon reduction and green energy, this paper also tries to reduce output power of dimmable LEDs, and then studies on the illuminations, received power and SNR under five study cases. From our simulations, the power can be saved up to 41.8% in the best case, and the SNR can also be increased to 18.9dB. While turning off the LEDs in the non-working area, we can save 75% power and reduce the interference. Thus, the peak SNR can achieve 27.9dB. The higher SNR means the data rate can be higher than 100Mbps if under the same BER requirement.