基于导频的OFDM无线通信信道估计算法

Channel estimation based on pilot-aided OFDM for wireless communication

信道估计是无线正交频分复用(OFDM)通信中的重要环节,直接影响OFDM通信的均衡效果和动态数据流分配。在最小二乘法(LS)信道估计算法的基础上提出了一种改进的信道估计算法,该算法在两个导频符号之间,利用前一个符号估计得到的信道频率响应来均衡下一个符号的信道频率响应,在两个导频符号之间形成一个判决反馈回路。这种算法不仅改善了LS信号估计算法单纯的线性关系,而且避免了误差扩散。实验结果表明,该算法计算简单,大大提高了系统的传输效率。

As an important part of Orthogonal Frequency Division Multiplexing(OFDM) wireless communication,channel estimation influences the balance effect and dynamic data flow distribution of OFDM communications directly.An improved channel estimation algorithm was proposed to improve the data transmission based on the Least Square(LS) channel estimation algorithm.It made channel frequency response between the two pilot symbols just as simple linear distribution.Pre-channel estimation value was used to equalize the next receiving symbol,thus made a feedback loop between the two pilot symbols.It not only improves the linear relationship but also avoids the proliferation of errors.The experiment results demonstrate that the algorithm improves the data transmission efficiency compared with the LS channel estimation algorithm.