Title :
Ultralow Noise Preamplifier and Optimization Method for Induction Magnetometers
Author :
Kai Liu ; Wanhua Zhu ; Bin Yan ; Leisong Liu ; Guangyou Fang
Author_Institution :
Key Lab. of Electromagn. Radiat. & Sensing Technol., Beijing, China
Abstract :
A 2 nV/√Hz and 10 fA/√Hz at 1-Hz ultralow noise preamplifier is designed to improve the sensitivity of the induction magnetometer (IM) from 0.1 Hz to 10 kHz. Meanwhile, the noise characteristics of IM are analyzed and distinguished. A novel optimization method to find the minimum length of the core under the required noise level and the limited IM weight is proposed. Furthermore, an optimal IM prototype from 0.1 Hz to 10 kHz is developed with the noise level of 1 pT/√Hz at 1 Hz and 1.5 fT/√Hz at 2 kHz. The length is only 360 mm and the weight is 1.5 kg. The measurement results of the IM also confirm the theoretical noise model and the optimization method.
Keywords :
magnetometers; optimisation; preamplifiers; IM; distance 360 mm; frequency 0.1 Hz to 10 kHz; induction magnetometer; mass 1.5 kg; optimization method; ultralow noise preamplifier; Coils; Magnetic cores; Magnetic fields; Noise; Optimization; Preamplifiers; Resistors; JFETs; induction magnetometer; noise measurement; offset compensation; optimization method; ultralow noise preamplifier;
Journal_Title :
Sensors Journal, IEEE
DOI :
10.1109/JSEN.2015.2389336
