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

Volume

15

Issue

6

fYear

2015

fDate

Jun-15

Firstpage

3293

Lastpage

3300

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;

fLanguage

English

Journal_Title

Sensors Journal, IEEE

Publisher

ieee

ISSN

1530-437X

Type

jour

DOI

10.1109/JSEN.2015.2389336

Filename

7004825