SCFDE系统改进的信道及噪声估计算法

Improvement on Channel and Noise Variance Estimation for SC-FDE Systems

论述了单载波频域均衡(Single CarrierFrequency Domain Equalization,SCFDE)系统模型,介绍了频域选择性信道模型,在传统的信道估计算法基础上,利用导频信号的时移特性,对一种改进的信道估计算法进行了分析。无论信噪比(Signal to Noise Ratio,SNR)及导频类型如何变化,该算法能得到2.1 dB的均方误差(Mean Square Error,MSE)性能提升。提出一种噪声方差的估计算法,当数据块达到30时,方差的估计跟理论很接近,且独立于信道估计误差。仿真表明,改进的算法也能适应时变信道。

The model of single carrier-frequency domain equalization is described. The frequency-selective channel is introduced. On the basis of traditional estimation algorithms, an improved channel estimation algorithm is analyzed by utilization of the time-shift property of the pilot signal. No matter how signal-to-noise ratio and pilot type vary, the improved estimation algorithm can achieve about 2. ldB performance gain for mean square error. In addition, a noise variance estimation algorithm is proposed. When the number of the data blocks reaches 30, the variance estimation approximates the theoretical value and is independent of the channel estimation errors. The simulation shows the improved estimation algorithm can also adapt to the time-variable channel.