一种适用于正交频分复用通信系统的信道估计盲算法

提出了一种适用于正交频分复用(OFDM)通信系统的信道估计盲算法,给出了该算法的理论基础和计算机仿真结果.该算法以子空间方法为基础,并利用了OFDM通信系统协议中的循环前缀信息.该算法还考虑了现有OFDM协议中的空闲子载波信息,并具有计算量相对较小、抗循环前缀长度不足和抗信道长度过估计等优点.

A Blind Channel Estimation Algorithm for Orthogonal Frequency Division Multiplexing Systems

We propose a new blind channel estimation method for orthogonal frequency division multiplexing (OFDM) systems. The method makes use of the redundancy introduced by the cyclic prefix (CP) to identify the channel based on a subspace approach. The method does not require any modification of the transmitter and applies to most existing OFDM systems. We also take consideration of the presence of null subcarriers in standardized OFDM systems. Compared with some existing methods, this approach has the following attractive properties: it has a lower computational complexity; it can estimate channels for OFDM systems with insufficient cyclic prefix; it performs well at low SNR; it performs well no matter where the channels′ zero locations are and is robust to channel order overestimation. Theoretical analysis and simulation results are provided to verify the above facts.