可見光通訊驅動電路之應用與研究

Abstract

根據目前的發光二極管（LED）將取代傳統的照明系統在不久的將來，由於耗電少，成本低，壽命長等優點。此外，LED的相對較高的調製速度,所以可用於可見光通信（VLC）。而VLC是不會受到電磁干擾（EMI）和可見光不用執照的許可。因此，它可以在射頻（RF）通信限制區域，如醫院或飛機上使用，在本論文中，我們第一部分，我們設計了合適的電流驅動器和電壓放大器為LED和光接收器（PD）分別為VLC加大驅動電流與驅動電壓。讓電流驅動器和電壓放大器可用於放大訊號使用，並透過RS232發送數位信號，VLC傳輸距離可顯著提高，在本文的第二部分中，我們提出並展示使用市售的太陽能電池SC-9728 6V 15 mA做為該VLC的接收器，透過調變將原本的頻寬2kHz提高，在論文的最後一部分，我們研究是否可使用液晶（LC）顯示下的背光源當作VLC發射器，並且去觀察接收後不同畫階的情況

It is believed that light-emitting-diode (LED) will replace the traditional lighting system in the near future, due to the less power consumption, low cost and long lifetime. Besides, the relatively high modulation speed of LED enables visible light communication (VLC). The VLC is electromagnetic interference (EMI) free and license free. Hence, it can be used in the radio-frequency (RF) communication restricted areas, such as hospital or airplane. In this thesis, we design and demonstrate the suitable current driver and voltage amplifier for the LED and PIN photo-diode (PD) respectively for the VLC. The current driver and voltage amplifier can be used to amplify the data signal transmitted using RS232 standard. In the second part of the thesis, VLC transmission distance can be significantly increased, we propose and demonstrate using commercial available solar cell as the VLC receiver. Through modulation bandwidth originally 2kHz can be increased ,In the final part of the thesis, we study using liquid crystal (LC) display as the VLC transmitter.