A new OFDM symbol synchronization for WMN used in railway

There exists an increasing strong demand for internet application in passenger trains, and the wireless broadband coverage along the whole railway is a prerequisite of the internet application in passenger trains. Wireless Mesh Network(WMN) based on 802.16 provides a new solution idea for the wireless broadband coverage of the railway, which is based on OFDM technology to support high-bandwidth data transmission in high-speed mobile environment. Orthogonal Frequency Division Multiplexing (OFDM) is the key technology of physical layer of WMN which has strong anti-interference ability, high bandwidth utilization and transmission rate. But there are some problems such as synchronization, channel estimation and Peak to Average Power Ratio(PAPR). Among these problems, synchronization is the most important one. For the classic Schmidl&Cox (S&C) timing synchronization algorithm existing plateau which leads to the synchronization inaccuracy, other improved algorithms are proposed to get better performance. However, drawbacks including the narrow synchronization range and the high computational complexity still exist. The optimized scheme mainly contains two aspects, one is amending the structure of the training sequence, and the other is improving the correlation algorithm. Above all, a new method is presented in this paper that optimizes the structure of the training sequence and improves the correlation algorithm to enhance the performance and support the high-speed mobile trains.