Adaptive Readout Schemes for Thin-Film Magnetoelectric Sensors Based on the delta-E Effect
Adaptive Readout Schemes for Thin-Film Magnetoelectric Sensors Based on the delta-E Effect
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DOI：
10.1109/jsen.2016.2553962
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发表时间：
2016-06-15
影响因子：
4.3
通讯作者：
Schmidt, Gerhard
中科院分区：
文献类型：
--
作者：
Reermann, Jens;Zabel, Sebastian;Schmidt, Gerhard
薄膜磁电传感器，即磁致伸缩和压电材料的复合材料，能够测量非常低的磁场。因此，此类传感器的应用可能是在不久的将来测量生物磁场。为了测量这些通常以低频分量为特征的信号，需要利用 Delta-E 效应等技术。迄今为止，此类传感器系统的检测限 (LoD) 尚未达到所需水平。为了改善这一点，提出了一种基于 Delta-E 效应的传感器系统自适应读出方案。其基础是使用单个传感器在接近共振频率的不同频率范围内同时进行测量。信号在信噪比方面得到最佳组合。提出并评估了两种组合方法。 LoD 方面实现了高达 6 dB 的改进。由于加权系数随时间的变化，所提出的方法可以被解释为一种降噪技术，这增加了此类传感器在实际测量场景中的可用性。
Thin-film magnetoelectric sensors, i.e., composites of magnetostrictive and piezoelectric materials, are able to measure very low magnetic fields. As a consequence, an application of such sensors could be, e.g., the measurement of biomagnetic fields in the near future. To measure these signals, typically characterized by low-frequency components, techniques, such as the delta-E effect, are utilized. The limit of detection (LoD) of such sensor systems did not reach the required level until now. In order to improve this, an adaptive readout scheme is proposed for sensor systems based on the delta-E effect. The basis is a simultaneous measurement with a single sensor at different frequency ranges close to the resonance frequencies. The signals are combined optimally in regard to their signal-to-noise ratio. Two combination approaches are presented and evaluated. An improvement up to 6 dB in terms of LoD is achieved. Due to an adaption of the weighting coefficients with time, the proposed method can be interpreted as a noise reduction technique, which increases the usability of such sensors in realistic measurement scenarios.