基于磁通负反馈的低噪声宽频带感应式磁传感器设计  

Design of low noise broad band IMS based on flux negative feedback

作　　者：应毓海[1,2] 

机构地区：[1]安徽大学电子信息工程学院,安徽合肥230039 [2]安徽广播影视职业技术学院信息工程系,安徽合肥230011

出　　处：《传感器与微系统》2014年第12期67-69,75,共4页Transducer and Microsystem Technologies

基　　金：国家高技术"863"研究发展计划资助项目(2009AA03Z442)

摘　　要：感应式磁传感器(IMS)是频率域电磁法(FEM)中使用最广泛的磁传感器,通常由感应线圈和前置放大器组成。为了增加IMS探测深度和微弱磁场信号的能力,基于磁通负反馈技术,获得其在低频段平坦的灵敏度曲线,拓宽了其观测频带。采用斩波前置放大技术,降低了1/f噪声对IMS的影响,对IMS的输出噪声进行了压制。通过在屏蔽室内对所研制的IMS性能进行测试,结果表明:其频带范围为0.001Hz^10kHz,输入噪声为3nV/Hz^(1/2),较3D-3磁传感器等效输入噪声提高了10.04dB,为其在实际项目应用提供了可靠的性能保障。Inductive magnetic sensor （IMS） is one of the most widely utilized magnetic sensors in frequency domain electromagnetic method （FEM） , which consists of inductive coil and preamplifier. In order to enhance capability of IMS to detect weak magnetic signals and depth, a flat sensitivity curve at low frequency band is achieved and observation band is broaden, which is based on flux negative feedback technology. Utilize chopper pre-amplifier technology to decrease effect of 1/f noise on IMS, and to suppress output noise of IMS. The performance of IMS is tested in shielded room, band range is of 0. 001 Hz - 10 kHz, and input noise is 3 nV/Hz1/2 , compared with magnetic sensor 3D-3, equivalent input noise is increased by 10. 04 dB, which guarantees performance for IMS in real project application.

关 键 词：感应式磁传感器 磁通负反馈 斩波前置放大 1/f噪声 

分 类 号：O657.3[理学—分析化学]