作者：徐强锋, 王学锋, 邓意成, 桑建芝, 卢向东, 孙晓洁
作者单位：北京航天控制仪器研究所，北京 100039
关键词：CPT磁力仪;EIT信号;弱磁测量;分离线宽
摘要：
针对现有磁力仪测量数百纳特斯拉弱磁场存在精度低和便携性差等问题，提出一种通过压窄CPT磁力仪EIT信号线宽来实现弱磁场测量的方法。该方法是根据EIT信号磁场测量仿真模型，采用相敏检波二阶微分信号获得磁力仪灵敏度系数，并根据最佳灵敏度系数分析得出EIT信号分离条件及其线宽对弱磁场测量性能的影响。仿真和试验结果表明：具有窄EIT信号线宽的CPT磁力仪，可实现100 nT磁感应强度值测量。最后，对EIT信号线宽压窄后的CPT磁力仪进行线性度和噪声测试，测试结果表明：在待测磁感应强度100~500 nT范围内，磁力仪测量的最大非线性误差为0.9537 nT；在100 nT背景磁场环境下，磁力仪输出噪声为20.26 pT/Hz1/2@1 Hz。
Influence of EIT signal on weak magnetic measurement performance of CPT magnetometer
XU Qiangfeng, WANG Xuefeng, DENG Yicheng, SANG Jianzhi, LU Xiangdong, SUN Xiaojie
Beijing Instuitute of Aerospace Control Devices, Beijing 100039, China
Abstract: Aiming at the problems of low accuracy and poor portability in measuring the weak magnetic field of hundreds of nT by the existing magnetometer, a method for measuring the weak magnetic field by narrowing the line width of the EIT signal of the CPT magnetometer was proposed, which based on the EIT signal simulation model of magnetic field measurement. The magnetometer's sensitivity coefficient was obtained by using the phase sensitive detection second-order differential signal. Then based on the best sensitivity coefficient analysis, the EIT signal separation conditions and line width on the weak magnetic field measurement performance were acquired. The simulation and test results showed that CPT magnetometer with narrow EIT signal line width can measure 100 nT magnetic induction. Finally, the linearity and noise tests of the CPT magnetometer were conducted after narrowing line width of the EIT signal. The test results showed that the maximum nonlinear error of the magnetometer was 0.9537 nT within the range of 100 ~ 500 nT of the magnetic induction. Under the background of 100 nT magnetic field, the output noise of the magnetometer was 20.26 pT/Hz1/2@1 Hz.
Keywords: CPT magnetometer;EIT signal;weak magnetic measurement;separation line width
2021, 47(2):170-176 收稿日期: 2020-03-09;收到修改稿日期: 2020-04-03
基金项目: 装备预研航天科技联合基金资助项目（6141B061105）
作者简介: 徐强锋(1995-),男,湖北黄冈市人,硕士研究生,专业方向为CPT磁力仪弱磁测量
参考文献
[1] OLSEN N, HULOT G, SABAKA T J. Measuring the earth’ s magnetic field from space: concepts of past, present and future missions[J]. Space Science Reviews, 2010(155): 65-93
[2] 王习东. 铷原子相干效应及CPT磁强计研究[D]. 武汉：华中科技大学， 2016.
[3] 桑建芝, 王学锋, 邓意成, 等. CPT原子磁力仪研究进展与发展趋势[J]. 战略与研究, 2018(63): 75-79
[4] 寇军, 康海霞, 杨然, 等. 原子磁力仪的空间应用及发展趋势[J]. 导航与控制, 2018, 17(6): 26-30
[5] LI J D, QUAN W, ZHOU B Q, et al. A Review of SERF atomic magnetometer: recent advances and applications[J]. IEEE, 2018, 20(18): 8198-8207
[6] KOMINIS I K, KORNACK T W, ALLRED J C, et al. A subfemtotesla multichannel atomic magnetometer[J]. Nature, 2003, 422(6932): 596-599
[7] SCHWINDT P D, KNAPPE S, SHAH V, et al. Chip-scale atomic-magnetometer[J]. Applied-Physics-Letters, 2004, 85(26): 6409-6411
[8] 单琎. 利用相干粒子数捕获(CPT)原理测磁的实验研究[D] 长春：吉林大学. 2010.
[9] 李琦. 相干粒子数俘获磁力仪[D]. 长春： 吉林大学. 2011.
[10] 梁尚清. 基于相干布局囚禁原理的磁场精密测量研究[D]. 杭州: 浙江大学. 2017.
[11] 孙伟民, 刘双强. 光学原子磁力仪[M]. 哈尔滨: 哈尔滨工程大学出版社, 2015.
[12] 胡曼青, 刘小河, 张伟. 三维超声波风速测量仪主控电路系统设计与实现[J]. 中国测试, 2020, 46(3): 97-102.
[13] ANDREAS P. ROLAND L. WERNER M et al. Control loops for a coupled dark state magnetometer[J]. IEEE, 2011(2): 779-784
