Adaptive frequency dependent gradiometry applied to SQUID magnetocardiography
Adaptive frequency dependent gradiometry applied to SQUID magnetocardiography
复制标题
自适应频率相关梯度测量法应用于 SQUID 心磁图
DOI：
10.1109/tasc.2003.813854
复制
发表时间：
2003
影响因子：
1.8
通讯作者：
H. Krause
中科院分区：
文献类型：
--
作者：
M. Bick;G. Panaitov;M. Schiek;Yi Zhang;H. Krause
在心磁图（MCG）的情况下，梯度测量是一种常用的方法，以减少环境噪声。这里，梯度仪的平衡是确定可实现的降噪的主要参数之一。在早期的工作中，我们报告了使用频率相关的梯度系数，以有效地平衡由信号和参考传感器组成的梯度计。在这项工作中，这些系数的自适应确定在测量过程中，而不干扰MCG信号的优点进行了研究。使用磁屏蔽内外的一阶和二阶高温SQUID梯度计记录MCG测量值。它将被证明，心脏信号不失真，通过应用我们的软件降噪技术。此外，通过在MCG测量期间重新计算梯度计系数，实现了改善的信噪比。确定了系数重算的最佳重复时间。
In the case of magnetocardiography (MCG), gradiometry is a commonly used method to reduce environmental noise. Here, the balance of the gradiometer is one of the main parameters determining the achievable noise reduction. In earlier work, we reported the use of frequency dependent gradiometer coefficients to effectively balance a gradiometer consisting of signal and reference sensors. In this work, the advantages of adaptive determination of these coefficients during a measurement without perturbing the MCG signal are investigated. MCG measurements were recorded with first and second order high temperature SQUID gradiometers inside and outside magnetic shielding. It will be shown that the heart signal is not distorted by applying our software noise reduction technique. Furthermore, by recalculation of gradiometer coefficients during the MCG measurement, an improved signal-to-noise ratio is achieved. The optimum repetition time for coefficient recalculation is determined.