易于硬件实现滤除ECG信号运动干扰的变步长LMS算法

摘要

In order to solve the problem that it is difficult to filter motion interference in electrocardio(ECG) signal monitoring system,an digital self-adaptive variable step-size least mean square(LMS)algorithm which is easy for hardware implementation is proposed.By simplifying the relationship between step-size factors and input signals,the algorithm reduces the computation of the weight updating system. Through analyzing unstablie convergence of traditional LMS algorithm,combined with iteration numbers to optimize the step-size factor,improve the convergence performance of the algorithm. Compared with the classical LMS algorithm,with computation slightly increased,convergence performance of the algorithm is greatly improved and the SNR is increased by more than 14 dB.Simulation results show that the algorithm has the advantages of small amount of computation and good to filter effect,while ECG sigal carry out realtime hardware integrated to filter motion interfernce.%针对移动心电(ECG)信号监测系统中运动干扰难以滤除的问题,提出了一种易于硬件实现的数字自适应变步长最小均方(LMS)算法.通过简化步长因子与输入信号的关系,减少了权值更新系统的运算量;分析传统LMS算法收敛性不稳定的问题,结合迭代次数优化步长因子,提高了算法的收敛性能.对比传统LMS算法,所提算法在运算量增加微小的情况下,收敛性能大幅提升,信噪比(SNR)增加大于14dB.仿真结果表明:算法在心电信号进行实时硬件集成滤除运动干扰方面具有运算量小,滤波效果好等优点.