脉冲噪声环境下信噪比的盲估计

正交频分复用(OFDM)系统中,多径信道下的传统信噪比估计采用的大多是加性高斯白噪声,本文提出了一种基于脉冲噪声环境下信噪比的盲估计方法。该方法首先设置合适的门限值抑制脉冲噪声,而后利用自相关函数的平稳特性估计出信道阶数,然后利用循环前缀数据为有用数据的复制这一特性估计出噪声功率,最后求出总的功率值从而估计出信号功率。实验仿真结果表明,提出的方法无需任何先验信息,在多径信道下具有良好的估计性能,且计算复杂度低。

Blind SNR estimation in the impulsive noise environment

According to that the traditional blind SNR estimation utilized the additive white Gaussian noise for orthogonal frequency division multiplexing (OFDM) system in multi-path channel conditions, a kind of method based on the impulsive noise environment SNR blind estimation was proposed. Firstly, the received OFDM signal was passed through a blanking nonlinearity element to suppress the impulsive noise at the receiver. Secondly, the channel order was roughly estimated by utilizing the cyclostationarity of autocorrelation function, and then estimated the noise average power by utilizing the characteristics that the data in cyclic prefix which was replication of part useful data. Finally, the signal average power was estimated from the last received signal power. The simulation results showed that the proposed method did not need any prior information and had better performance and lower computation complexity in multi-path channel.