基于改进最小方差波束成形的心磁信号的源重建  

Source reconstruction from magnetocardiography signals based on improved minimum variance beamforming

作　　者：徐俊 朱俊杰[1,2] XU Jun;ZHU Junjie(School of Electrical Engineering and Automation,Henan Polytechnic University,Jiaozuo 454003,China;Henan Key Laboratory of Intelligent Detection and Control of Coal Mine Equipment,Jiaozuo 454003,China)

机构地区：[1]河南理工大学电气工程与自动化学院,河南焦作454003 [2]河南省煤矿装备智能检测与控制重点实验室,河南焦作454003

出　　处：《中国医学物理学杂志》2024年第7期870-875,共6页Chinese Journal of Medical Physics

基　　金：国家自然科学基金(61601173)。

摘　　要：由于冠心病患者的心磁图在信噪比较低时,最小方差波束成形(MV)方法的源重建效果不理想,提出一种基于改进最小方差波束成形(IMV)方法,在MV方法的基础上,使用导联矩阵和磁场信号二阶特征矩阵组成约束矩阵,构造新的空间滤波器的权矩阵,从而降低输出噪声功率增益。利用点扩散函数理论比较IMV方法和MV方法的空间谱估计的单源分辨率;利用3个电流偶极子产生36通道磁场仿真数据,采用IMV方法和MV方法在低信噪比下对仿真数据进行源重建;最后对3名冠心病患者的36通道心磁图的R波峰和T波峰时刻数据进行源重建。结果表明,IMV方法的单源分辨率更高,对仿真数据及冠心病患者心磁数据的重建精度更好。Given the poor source reconstruction results of minimum variance beamforming(MV)for magnetocardiogram(MCG)at low signal-to-noise ratio in coronary heart disease patients,a novel method using the improved minimum variance beamforming(IMV)is proposed.Based on MV,the proposed method uses the lead matrix and the magnetic field signal second-order characteristic matrix to form a constraint matrix,and constructs the weight matrix of a new spatial filter,thus reducing the output noise power gain.The single-source resolution of IMV and MV spatial spectrum estimations is compared using the point spread function.IMV and MV are used to perform source reconstruction from the 36-channel magnetic field simulation data generated by 3 current dipoles at low signal-to-noise ratio;and the source reconstruction is also carried out on the R-wave peak and T-wave peak time data of 36-channel MCG of 3 coronary heart disease patients.The results show that IMV has higher single-source resolution and reconstruction accuracy for simulation data and MCG data from coronary heart disease patients.

关 键 词：心磁图 改进最小方差波束成形 逆问题 空间滤波器 源重建 

分 类 号：R318[医药卫生—生物医学工程] TN911.7[医药卫生—基础医学]