Research And Implementation Of Visible Light Communication Technology Based On Mobile Phone

The radio frequency band becomes increasing congestion due to the limitation of wireless spectrum resources in recent years. It is increasingly difficult for traditional wireless communication to increase communication rate and capacity. However, visible light communication(VLC), which has a higher available bandwidth, grater communication capacity, faster transmission rate and stronger anti-electromagnetic interference ability, has attracted focus of researchers. VLC becomes a research hotspot in the field of communication.VLC has received lots of attention and made great development in recent years. However, it is not enough yet. There are still many problems when utilizing VLC in practical conditions. Most of the studies using Avalanche Photo Diode (APD) as the receiver to detect the visible light signal. Then data received by APD is processed off-line. The APD is expensive and not easy to carry,which is not feasible for practical application.In this paper, based on ambient light sensor and camera sensor, two different receiving methods of visible light signal are experimentally studied. The detail research contents and conclusions are as follows:(1) Design appropriate LED driver circuit and make LED send visible light signal successfully.(2) Know about the development of smart phones, basic structure,operating system and so on. Select Google's Android system for more information. Study the program development procedure of Android and the method of using camera and light sensor.(3) Set up the experiment platform of visible light communication.Study the effect of data processing method with MATLAB and make it true with JAVA program language. Finish the data processing in mobile phone finally.(4) For camera sensor, we can transmit data with 2kbps data rate over 0.3m. For light sensor, we can transmit data with 0.2kbps data rate over 2m. All data processing is accomplished in the mobile phone.In a word, our studies focus on the feasibility of using mobile phone to receive visible light signals. We study two different receiving methods of visible light signal using ambient light sensor and camera sensor in mobile phone. The results show that our schemes are available, which is significant for promoting the practical application of VLC technology.