GFDM系统中基于扩展卡尔曼滤波的ICI消除

ICI Cancellation Based on Extended Kalman Filter in GFDM System

针对广义频分复用(GFDM)系统中由于载波频偏(CFO)的存在而产生的载波间干扰(ICI)效应,提出了一种基于扩展卡尔曼滤波的ICI消除算法。通过获取上一状态的频偏最优化估计值及其协方差,进行当前频偏状态预测,利用受到ICI影响的接收数据符号和频偏估计量计算出频偏校正值。通过仿真测试,在信噪比较大的情况下,改善了系统的误码率,最佳性能达到均方误差(MSE)为10-4的精度。将扩展卡尔曼滤波方法与标准GFDM、自消除方法相比较,在频谱较大的场景下,误码率性能具有明显的优势。

To deal with the intercarrier interference(ICI) effect in generalized frequency division multiplexing(GFDM) systems due to the existence of carrier frequency offset(CFO),an ICI cancellation algorithm based on extended Kalman filter(EKF) is proposed.By obtaining the optimal estimation of frequency offset and its covariance of the previous state,the current frequency offset state is predicted,and the frequency offset correction value is calculated by using the received data symbols and frequency offset estimators affected by ICI.The simulation test shows that,under the condition of large signal-to-noise ratio,the bit error rate of the system is improved,and the best performance achieves the accuracy of mean square error(MSE) of 10-4.Compared with the standard GFDM and self-cancellation methods,the extended Kalman filter has obvious advantages in the case of large spectrum.