光信号接收的定时同步算法研究

Research on Timing Synchronization Algorithm for Optical Signal Receiving

针对可见光通信和正交频分复用的信号调制的特点,在传统算法基础上,从定时测度函数和训练序列结构两个方面提出改进,利用最大滑动自相关原则,进行能量归一化,解决"相关峰平台"问题,实现符号精准定位。仿真结果表明:无论在AWGN信道还是在多径衰落信道中,改进算法都能保证优良的定时同步性能和通信低误码率。尤其在低信噪比的条件下,改进算法的误码率在0.3左右,而S&C算法的误码率高达0.9以上。

In view of the characteristics of VLC and OFDM signal modulation,this paper proposes,on the basis of the traditional algorithm,improvements from two aspects: the timing measure function and the training sequence structure. Using the principle of maximum sliding auto-correlation,we can normalize energy,solve problems of " correlation peak platform" and realize accurate positioning of symbols. The simulation results show that the improved algorithm can ensure the excellent timing synchronization performance and the low bit error rate of communication in both AWGN channel and multipath fading channel. Especially under the condition of low signalto-noise ratio,the bit error rate of the improved algorithm is around 0. 3,while the bit error rate of the S & C algorithm is over 0. 9.