MIMO-OFDM系统基于DFT的LS信道估计算法

DFT-based LS Channel Estimation Algorithm for MIMO-OFDM Systems

精确的信道估计是提高多输入多输出正交频分复用(MIMO-OFDM,Multiple Input Multiple Output-Orthogonal Frequency Division Multiplexing)系统性能的关键,针对现有的信道估计算法的不足,提出了一种基于DFT的最小二乘(LS,Least Square)信道估计算法,利用噪声方差设定一个门限进行阈值,进一步消除噪声干扰,充分利用了时变无线信道中时域和频域的相关性,改善了信道估计的性能。为验证其有效性进行了仿真。仿真结果表明,在慢时变信道环境下,改进方法可以进一步提高信道估计的精度,同时保持了较低的复杂度。

Accurate channel estimation in multiple input multiple output orthogonal frequency division multiplexing（MIMO-OFDM）systems is the key to improvement of the system performance.For deficiency of the existing channel estimation algorithms,a DFT-based LS channel estimation algorithm is proposed,which with the estimation of the noise power variance,could achieve a threshold and thus remove the noise further.This algorithm by taking full advantage of correlation between time domain and frequency domain in time variant wireless channel,could improve the performance of channel estimation.Simulation results show that the proposed method is of low complexity and could further raise the accuracy of channel estimation under slow time-varying channel environment.