结合平滑时窗-最小二乘法的光泵磁力仪快速高精度频率测量方法

A Fast and High-precision Frequency Measurement Method of Optical Pump Magnetometer Combined with Smooth Time Window-Least Square Method

为了提高光泵磁力仪频率测量的精度和速度,提出了一种结合平滑时窗-最小二乘法的光泵磁力仪快速高精度频率测量方法。首先,根据光泵磁力仪频率信号的特点,分析了该方法的测量原理和实现方法。然后,推导了频率测量的公式,分析了影响频率测量精度的因素。最后,设计频率测量实验和室外磁场测量实验对提出的方法进行验证。实验结果证明,该方法明显优于多周期同步测频法,在80~350 kHz频率段内均方差均小于2.2×10^(-3)Hz,在磁场测量实验中,采样频率为200 Hz时,噪声功率谱密度为0.001 nT√Hz@1Hz。

In order to improve the precision and speed of frequency measurement of optical pump magnetometer,a fast and high precision frequency measurement method of optical pump magnetometer combined with smooth time windowleast square method is proposed.Firstly,according to the characteristics of the frequency signal of optical pump magnetometer,the measurement principle and realization method of the method are analyzed.Then,the formula of frequency measurement is deduced,and the factors that affect the precision of frequency measurement are analyzed.Finally,experiment and an outdoor magnetic field measurement experiment are designed to verify the proposed method.The experimental results show that the method is obviously better than the multi-period synchronous frequency measurement method,and the mean square error in the frequency range of 80~350 kHz is less than 2.2×10^(-3) Hz.In the magnetic field measurement experiment,when the sampling frequency is 200 Hz,the noise power spectral density is 0.001 nT√Hz@1Hz。