摘要
随着现代轨道交通旅客信息系统(PIS)的广泛使用,PIS系统视频流的车/站互传的流量预测问题变得更加重要。在旅客信息系统通过无线信道传输的视频流,通常不具有任何先验统计特性,而无线资源管理过程中又非常需要关于视频流量的可预测统计信息。基于这种需要,本文提出一种快速视频混沌特性检测的方法。该方法通过计算序列的最大Lyapunov指数分析其混沌特性,为使用混沌的预测方法估计视频传输流量进行预判决。在对Lyapunov指数进行计算前,先对数据进行预处理,在不损失数据内在特征的前提下,明显地降低计算量。通过对实际数据的仿真验证,证明该算法在判断准确性、实时性等方面均表现良好。
Along with wider and wider use of the Passenger Information System （PIS） in modern railway communication, it has become more andmore important to predict the video traffic between the vehicle and the sta- tion. Video traffic transferred by wireless channels in the PIS system usually has no transcendent statistic fea- tures, however the predictable statistic information of video traffic is badly needed in wireless resource management. Based on the requirements, a method of fast detecting the chaotic characteristics of the video sequences is proposed. By calculation of the largest Lyapunov exponent, the chaotic characteristics of the given sequences are analyzed. Data pretreatment lowers the amount of calculation without losing the inside characters. Experimental results show that the proposed method performs well in real-time ability, veracity of chaotic characteristics detection and so on.
出处
《铁道学报》
EI
CAS
CSCD
北大核心
2008年第4期28-31,共4页
Journal of the China Railway Society
基金
国家自然科学基金资助项目(60402035)
