一种MC-CDMA系统LS信道估计的改进算法

An Improved LS Channel Estimation Algorithm in MC-CDMA Systems

LS信道估计算法计算量小,实现简单,但是受噪声的影响信道估计精度低。为降低噪声对信道估计精度的影响,提出一种基于DFT的LS信道估计改进算法。该算法利用MC-CDMA中闲置的虚载波对信道噪声功率进行估计,通过将LS信道估计的时域响应限制在循环前缀长度内并进一步通过设置门限值忽略LS信道时域响应在循环前缀长度内的噪声分量和无效径响应,显著提高了信道估计精度。本文的算法运算量小,实现简单,信道估计精度高,仿真结果验证了算法的有效性。

LS channel estimation algorithm has low computation complexity and is easy to be implemented,but has low accuracy because of the influence of channel noise. To increase the accuracy of channel estimation, an improved LS algorithm based on DFT was presented in this paper. The algorithm in this paper increases the accuracy through restricting the channel response to the length of CP and ignoring channel noise and invalid channel response based on the noise power estimated with the virtual carriers in MC-CDMA. The algorithm described in this paper has low complexity and high accuracy and is validated by computer simulation.