基于低通滤波器的原子钟时差测量数据降噪处理及其性能分析  

Noise reduction processing of atomic clock differential measurement data based on low-pass filter and its performance analysis

作　　者：李宗源 袁海波[1,2,3] 张虹 张继海[1] 刘素芳[1,2] 王一桁 LI Zong-yuan;YUAN Hai-bo;ZHANG Hong;ZHANG Ji-hai;LIU Su-fang;WANG Yi-heng(National Time Service Center,Chinese Academy of Sciences,Xi’an 710600,China;University of Chinese Academy of Sciences,Beijing 100049,China;Key Laboratory of Time Reference and Applications,Chinese Academy of Sciences,Xi’an 710600,China)

机构地区：[1]中国科学院国家授时中心,西安710600 [2]中国科学院大学,北京100049 [3]时间基准及应用重点实验室(中国科学院),西安710600

出　　处：《时间频率学报》2024年第3期171-179,共9页Journal of Time and Frequency

基　　金：科学技术部国家天文科学数据中心时间频率数据库(NADC2022YX01-05)。

摘　　要：时间间隔计数器是守时中获取原子钟比对数据最常见的比对设备,但其获取的比对数据会受硬件性能、被测信号质量和测量方法的影响,在测量脉冲信号之间的时间差时,引入一定的不确定度。直接使用原始数据对原子钟中短期稳定度评估可能会带来不可忽略的影响,简要分析了经Savitzky-Golay滤波器降噪后的计数器测量噪声与频率稳定度之间的关系,并结合K折交叉验证方法确定了滤波器各项参数,以避免滤波失真。实验表明在滤波器多项式阶数为2,窗口宽度为141时,所获得的时差数据滤波后能够准确反应被测原子钟平均时间为100 s及以上的频率稳定度,为准确评估原子钟的短期稳定度提供了一种有效的数据处理方法。The time interval counter,a common device for obtaining atomic clock comparison data,is influenced by hardware performance,signal quality,and measurement methods,introducing uncertainty in measuring the time interval of pulse signals.Directly using raw data to evaluate the short-term frequency stability of atomic clocks will result in a noticeable impact.To accurately estimate the short-term frequency stability,it is crucial to process the measurement data.This article analyzes the relationship between counter measurement noise and frequency stability after applying the Savitzky-Golay filter,and determines the filter parameters with the k-fold cross-validation method to avoid the filtering distortion.Experiments show that a filter with a polynomial order of 2 and window width of 141 accurately reflects the frequency stability of atomic clocks with an average time of 100 seconds or more,providing an effective data processing method for short-term stability assessment.

关 键 词：频率稳定度 时差测量 噪声处理 Savitzky-Golay滤波器 

分 类 号：TM935.115[电气工程—电力电子与电力传动]