基于IEEE802.16e的OFDM定时同步算法及FPGA实现

Timing Synchronization Algorithm of OFDM Based on IEEE802. 16e and its Implementation with FPGA

针对IEEE802.16e的正交频分复用(Orthogonal Frequency Division Multiplex,OFDM)定时同步问题,在分析IEEE802.16 e协议定义OFDM前导训练序列特征的基础上,提出了一种基于前导训练序列的互相关定时同步算法。通过采用差分运算来降低载频频偏对同步性能的影响,采用量化处理技术以简化算法运算复杂度,并采用Xilinx公司的XC5VSX95T芯片进行FPGA实现验证。理论分析和仿真结果表明,算法能有效实现定时同步功能,对载波频偏不敏感,抗噪性能好,硬件资源利用率高,具用实时处理能力。

This paper focuses on timing synchronization of OFDM based on IEEE802.16e. By analyzing the characteristics of a preamble sequence defined in IEEES02.16e standard, a cross-correlation method using a preamble sequence of OFDM timing synchronization is presented.The method decreases the influence of frequency offset on timing synchronization performance by using differential calculation,reduces the computation complexity by using quantization processing, and the method is implemented with FPGA by using XCSVSX95T of Xilinx Company.The theoretical analysis and simulations are carried out.The simulation results show that the algorithm can effectively implement timing synchronization capability, insensitivity on carrier frequency offset, good anti-noise performance, high FPGA hardware resource utilization and real-time processing.