摘要
数据依赖叠加训练序列(Data-Dependent Superimposed Training,DDST)常用在正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)的信道估计中,由叠加训练序列和数据依赖序列组成,与信息序列并行发送,可以提高带宽利用率。提出了一种基于数据依赖叠加训练序列的OFDM载波频偏估计方法。叠加训练序列的周期性使其DFT能量间隔分布在特定的频点上,利用这个特性可进行频偏估计,只有得到正确的频偏估计时,这些特定频点的能量才得到最大值。仿真表明该方法在不降低传输速率的情况下,有着较好的频偏估计性能。
DDST sequence is often employed in channel estimation of OFDM system. It is composed of superimposed training sequence and data-dependent sequence, and is transmitted in parallel with information sequence, improving the bandwidth utilization. The paper proposes a novel method of CFO （Carrier Frequency Offset） estimation in OFDM system based on maximizing the special frequency domain power of DDST sequence.The superimposed training sequence＇ s DFT power are distributed at intervals in specific frequency points due to the periodicity of sequence,and this characteristic can be used to estimate the CFO. Only when correct CFO is obtained to compensate the received signal, the power of specific DFT points of received signal could reach the maximum. Simulation results show that this method could accurately estimate the CFO without reducing the transmission rate.
出处
《无线电通信技术》
2011年第1期62-64,共3页
Radio Communications Technology
