基于相位调制技术的可见光通信系统码间干扰识别研究

Identification of ISI in visible light communication system based on phase modulation technology

室内可见光通信系统的传输信道易受到多径效应产生严重码间干扰,降低通信质量,为此提出了相位调制技术的可见光通信系统码间干扰识别方法。通过构建可见光通信系统信道模型,针对信道光源之间在时域和频域上形成的重叠光信号在多径效应作用下,产生的码间干扰,利用位调制技术对系统信道展开均衡设计,并依照多径扩展统计限定码元速率均值,实现码间干扰抑制。结果表明:本文方法有效调制室内可见光通信系统传递出的信号码元,消除码间干扰对传输信号产生畸变失真,降低系统误码率、误比特率、均方误差以及功率峰均比,大幅度提升了数据传输质量和通信可靠性。

The transmission channel of indoor visible light communication system is prone to serious inter symbol interference caused by multi-path effect,which reduces the communication quality.Therefore,the identification method of inter symbol interference of visible light communication system based on phase modulation technology is proposed.By constructing the channel model of visible light communication system,regarding the inter symbol interference caused by multi-path effect of overlapping optical signals formed among channel light sources in the time and frequency domain,the bit modulation technology is used to carry out the equalization design of system channel,and according to the multi-path expansion statistics,the average rate of the limited symbols is determined to achieve inter symbol interference suppression.The results show that this method can effectively modulate the signal symbols transmitted by indoor visible light communication system,eliminate the distortion caused by inter code interference,reduce the system code error rate,bit error rate,mean square error and power peak-to-average ratio,and greatly improve the quality of data transmission and the communication reliability.