射频干扰环境下OFDM系统的盲信号干扰噪声比估计  

Blind SINR estimation for OFDM system in the presence of radio frequency interference

作　　者：洪顺利[1,2] 李有明[1] 金明[1] 王刚[1] 

机构地区：[1]宁波大学通信技术研究所,浙江宁波315211 [2]浙江交通职业技术学院信息学院,浙江杭州311112

出　　处：《通信学报》2014年第6期126-131,共6页Journal on Communications

基　　金：国家自然科学基金资助项目(61071119);浙江省教育厅科研基金资助项目(Y201224625);宁波市自然科学基金资助项目(2012A610017)~~

摘　　要：基于OFDM信号的循环平稳特性,提出一种在射频干扰环境下OFDM系统的盲信号干扰噪声比估计方法。通过分析发送信号,射频干扰信号以及高斯白噪声的周期自相关函数能量分布规律,选取合适的延时变量和循环频率在功率谱域能有效分离信号功率和干扰加噪声功率分量,从而估计出信号干扰噪声比值。计算机仿真结果表明,和经典的二阶四阶矩(M2M4,second-order and fourth-order moments)盲信号干扰噪声比估计方法相比,新方法不仅能够有效估计射频干扰环境下OFDM系统的信号干扰噪声比值,而且无论是估计性能还是复杂度都优于M2M4方法;同时在快衰落Rayleigh信道下,新方法也能有效地估计出信号干扰噪声比值。进一步,所提方法具有对射频干扰信号密度不敏感的优点。Based on cyclostationarity propeTties of OFDM signal, a novel blind SINR estimation method for OFDM sys- tem in the presence of RFI was proposed. By analyzing the power distribution of cyclic correlation of transmitted signal, RFI and AWGN, appropriately selecting the time delay variable and cyclic frequency of the OFDM signal, the signal and interference plus noise power could be efficiently isolated in the power domain, which formed the SINR estimation method. Computer simulation results verify that the performance of the proposed method is superior to that of sec- ond-order and fourth-order moments （M2M4） method and the complexity of the new method is also lower than that of the M2M4 method. The new method can also effectively estimate SINR under the fast fading Rayleigh channel. Furthermore, the new method is robust to the density of RFI signal.

关 键 词：OFDM 循环平稳特性 射频干扰 信号干扰噪声比 

分 类 号：TN92[电子电信—通信与信息系统]