基于磁通门和磁阻传感器的混合宽带磁传感器的研究与设计

Research and Design of Hybrid Magnetometer Based on Fluxgate and TMR

在地磁探测领域,被测磁信号幅值范围和频率范围都较宽,文中利用磁通门传感器低频段噪声密度低,TMR传感器工作频率高、高频段噪声密度低的特点,根据互补滤波的数据融合方法,对磁通门和TMR分别进行低通和高通滤波,并在FPGA平台上通过数字滤波和比较判断的数据融合方式,将2种传感器的输出在频带上进行“拼接”,实现了两种磁传感器的数据融合。经测试混合磁传感器的频带拓展至10 kHz,灵敏度为0.113 mV/nT,测量范围±0.8 Gs,峰峰值噪声0.5 nT。

In the field of geomagnetic detection,the amplitude and frequency of the measured magnetic signal are wide.In this paper,flux gate sensors have characteristics of low noise density at low frequency,TMR sensors have characteristic of high working frequency and low noise density at high frequency.According to the data fusion method based on complementary filtering,the fluxgate and TMR are respectively filtered by low pass and high pass,through digital filtering and comparison of data fusion methods on FPGA platform,the output of the two sensors is“spliced”in frequency band to achieve the data fusion of two magnetic sensors.After testing,the frequency band of the hybrid magnetic sensor is extended to 10 kHz,the sensitivity is 0.113 mV/nT,the measurement range is±0.8 Gs,and the peak-to-peak noise is 0.5 nT.