基于虚拟子载波的盲信道估计改进算法

Improved blind channel estimation algorithm for OFDM by exploiting virtual carriers

提出了一种改进算法，该算法基于虚拟子载波的子空间算法，利用循环前缀（CP）引入的信息冗余，由于OFDM传输方程不能直接推导子空间算法，故首先给出一种新的方法对OFDM传输方程作矩阵变换，从而得到一个结构简单的新方程，基于这个新方程推导子空间算法。系统分析及仿真结果表明，在信噪比为20dB的条件下，与已有算法相比可以有7dB的性能提高且在收敛速度上和已有算法相比．快500～800个符号。

In this paper, an improved subspace- based algorithm is proposed by exploiting virtual carriers. By changing the transmission equation, the new method derives a new subspace algorithm from the new transmission equation. Comparison of the proposed method with the old method by computer simulation illustrates that effectiveness of the proposed method with regard to both estimation accuracy and speed of convergence has improved.