为了提高可见光通信(VLC)的频谱利用率,提出一种多维编码方法,从编码原理和性能上进行了理论分析,在此基础上构建了基于RGB发光二极管(LED)的可见光视音频传输系统,并对该编码方法进行了实验验证。实验对多基色LED采用16脉冲位置调制(16-PPM)作为基调制的多维编码方法,在3m距离上实现了1.5Mbit/s的视音频数据流传输。结果表明,多维编码方法可以有效利用可见光的宽频谱,提高信道容量,为进一步实现高速通信系统提供了可能。
In order to improve the spectrum utilization in visible light communications (VLC), a new multi- dimension encoding scheme is proposed and its encoding principle and performance are analysed. A VLC system to transmit high quality video and audio signal is demonstrated. The system uses RGB light emitting diode (LED) as source, which is encoded by the multi-dimension encoding scheme with 16 pulses position modulation (16-PPM) as a base modulation, and achieves the video stream communication in the distance of 3.0 m and at the rate of 1.5 Mbit/s. The results show that the method can take fully the advantage of the vast frequency resources provided by light, improve the channel capacity and provide the possiblity of high-speed communication systems.