铯光泵磁力仪测频方法的研究和实现

铯光泵磁力仪需要通过测量磁共振频率换算得到被测磁场值。以全同步测频方法为基础，提出一种改进的测频方法，并进行了误差分析。通过判断连续两次测量中的被测信号周期个数是否一致对计数值进行处理，二者一致时进行频率换算，否则计数值被丢弃。通过该方法可以将最大误差减小到原来的一半。设计了基于FPGA的测频系统，对改进的方法进行验证，结果表明，改进后方法的误差明显下降，证实了改进方法的有效性。被测频率换算成对应磁场值，改进方法的测频的绝对精度满足设计要求。

Research and Implementation of Frequency Measurement Method for Cesium Optically Pumped Magnetometer

It is necessary for cesium optically pumped magnetometer to measure magnetic resonance frequency and change it to magnetic field intensity. An improved method was proposed to reduce errors based on complete synchro?nization frequency measurement method. When the numbers of measured signal cycles in two consecutive measure?ments are the same,the count value will be used to calculate the frequency of the measured signal,or it will be dis?carded. The biggest error of the improved method is as half as the original method.A FPGA-basedfrequency mea?surement system was designed and implemented. The results of the experiment show that the improved method can effectively reduce errors and the absolute accuracy changed tomagnetic field intensity meets the design requirement.