摘要
传统的直接电测量方法受1/f噪声限制,在低频处信号与噪声发生混叠,难以实现高水平低噪声测量。该文提出一种基于电/磁转换的海洋电场低噪声检测方法,将电信号转化为磁信号,通过微机械的方法将磁信号调制到高频,有效避开低频1/f噪声影响。设计一种实现电/磁转换功能的微机械结构,利用TMR电阻构成惠斯通电桥测量磁信号,实现海洋电场的高水平低噪声检测。仿真与实验结果在1 Hz处噪声分别达到1.16 nV/(Hz)^(1/2)和1.41 nV/(Hz)^(1/2),优于传统电测量方案的噪声水平,验证该方法的有效性。
Limited by 1/f noise, traditional electrical measurement has difficulties in achieving high-level low noise characterization as a result of signal aliasing with noise at low frequency. In this article, a new weak marine signal low noise detection technique based on electric/magnetic conversion method was proposed. Electric signal was converted into magnetic signal, and then modulated to high frequency through micromechanics, which could avoid the impact of low frequency 1/f noise. Structure based on electric/magnetic conversion was designed. TMR based Wheatstone bridge was used in magnetic signal measurement to realize marine signal＇s high-level characterization. The results of simulation and experiment show that the low frequency noise of this module can reach 1.16nV/√Hz and 1.41nV/√Hz at 1Hz respectively, which is better than normal low- noise pre-amplifier, illustrating the effectiveness of this magnetic measuring current model.
出处
《中国测试》
北大核心
2017年第4期125-129,共5页
China Measurement & Test
基金
国家自然科学基金(51507178
U1430105
51175507)
关键词
海洋电场
低噪声
1/f噪声
电/磁转换
微机械调制
marine electric field
low noise
1/f noise
electric/magnetic conversion
micromechanicsmodulation
