OFDM系统中线性插值信道估计器的性能研究

Research of Channel Estimation Using Linear Interpolation Technology in OFDM Systems

为了得到由线性插值信道估计器本身精度造成的插值误差与噪声所带来的误差间的定量关系,通过基于一阶线性插值的OFDM系统梳状导频信道估计器和块状导频信道估计器误差性能的分析,推导出了插值误差和高斯噪声对估计器性能影响的数学表示式,并得出了线性插值信道估计器导频间距的选择规范;最后,在IEEE802.11 a环境下进行了系统仿真,仿真结果表明,插值误差与插值带来的噪声降低二者存在折衷,并且在室内环境中具有相同导频间距的梳状导频估计器比块状导频信道估计器性能优越。

To describe the definite relationship between interpolation error induced by precision inefficient and noise error, an analysis of MSE performance of comb-type estimator and block-type estimator based on linear interpolation in OFDM system is discussed in this paper as there is no literature focus on it by now, and also formulae illustrating the effect of interpolation error and noise reduction to system performance are deduced then, a criterion for linear interpolation channel estimator pilot sub carries interval selection is derived. Simulation resuhs which based on Hiperlan/2 show that the MSE performance of comb-type estimator when with the same pilot sub carriers interval is better than that of block-type estimator in indoor circumstances.