频率选择性衰落信道下OFDM子载波数盲估计

摘要

提出了一种在频率选择性衰落信道下的基于高阶循环累积量的OFDM信号子载波数盲估计方法,扩展了该方法的适用范围,并进行了理论推导和试验仿真.结果表明OFDM信号的特定高阶循环累积量仅在子载波位置存在,通过检测循环频率的个数可以估计出子载波数.高阶累积量具有良好的抗噪性能,在低信噪比下具有良好的估计性能.%In this paper, the high-order cyclic cumulants to estimate the sub-carriers of OFDM signals in frequency-selective fading channel is exploited, and it is proved by theoretical analysis. Simulation results show that the specific four-order cyclic cumuLants of the OFDM signal exit only at the location of its sub-carders. So the sub-carriers estimation can be implemented by detecting the cyclo-frequenciers. Due to the fact that the high-order cyclic cumulants can suppress the Gaussian noise, the proposed estimator performs well at low SNR.