叠加弱能量序列的OFDM系统时频同步方法

Timing and Frequency Synchronization Algorithm with Superimposed Weak Power Sequence for OFDM Systems

本文提出一种使用叠加的、弱能量序列进行时间同步和频偏估计的方法,其中所构造的训练序列具有低/零自相关性及弱能量性能,该序列被叠加在信息符号上并仅分配发射机总能量的4.1%;传统利用循环前缀信息估计频偏范围只局限于0.5内,该法使频偏估计范围可达到1,在利用本地序列与接收信号的相关性后可使整个频偏估计范围达到1/4带宽.理论和仿真表明,该法具有比常规算法更优的时间估计精度和频偏估计范围.

A novel tirning and frequency synchronization method by superimposed sequence with lower power was proposed for OFDM systems. The training sequence, which was constructed and had low/zero autocorrelation and weak energy performance, was superimposed with total energy accounted for only a transmitter total power 4.1 percent on the information symbol. The novel frequency offset estimation range using guard interval is enlarged from 0.5 to 1, while the total frequency offset estimation range is 1/4 bandwidth. Theory and simulation show that the performances of the proposed algorithm are much better than those of the con- ventional schemes in accuracy and the mean square error.