原子钟时域频率稳定性计算方法

兑水

郭海荣　[1,2] 郭树人　[3] 焦文海　[3] 周鸿伟[3]

[1]信息工程大学测绘学院,河南郑州450052
[2]北京航天飞行控制中心,北京100094
[3]北京跟踪与通信技术研究所,北京100094

摘　要:首先给出时域频率稳定性分析中各种方差的实用计算公式，并在此基础上分析各种方差特性，总结归纳其适用范围。分析表明：①阿仑方差是时域频率稳定性分析中最常用的方法，但不能区分调相白噪声和调相闪变噪声；②改进阿仑方差通过相位平滑运算能识别这2种噪声；③时间方差和时间总方差主要用于描述频率源的时间波动，主要用于分析调相噪声；④当频率漂移项较大或受甚低频噪声影响时，哈达玛系列方差能给出很好的测量特性。[著者文摘]

关键词:原子钟 频率稳定性 置信区间 等效自由度Computation of the Time-domain Frequency Stability of Atomic ClocksGUO Hai-rong, GUO Shu-ren, JIAO Wen-hai,ZHOU Hong-wei1. Institute of Surveying and Mapping, Information Engineering University, Zhengzhou, Henan Province 450052; 2. Beijing Aerospace Control Center, Beijing 100094; 3. Beijing Institute of Tracking and Telecommunications Technology, Beijing 100094Abstract:Calculation formulas for various variances are first given in this paper and they are used in analysis of timedomain frequency stability. Then, the characteristics of the variances are analyzed together with a summary of their applications. Comparisons and analysis show the following： （ 1 ） Allan variance is the most common method for analyzing time-domain frequency stability of atomic clocks, but white PM and flicker PM cannot be separated ; （2） Modified Allan variance can separate the two PM noises by phase average operation; （3） Time variance and its total estimator are mainly used for analyzing the time fluctuations of an atomic clock, that is to say, it is mainly used for analyzing PM noises; （4） Hadamard variance provides the preferred statistics in situations when the frequency drift is above the very low frequency noise effect.[著者文摘]

Key words:Atomic Clock; Frequency Stability; Confidence Interval; Equivalent Degrees of Freedom