原子鐘時域頻率穩定性計算方法

郭海榮　[1,2] 郭樹人　[3] 焦文海　[3] 周鴻偉[3]

[1]信息工程大學測繪學院,河南鄭州450052
[2]北京航天飛行控制中心,北京100094
[3]北京跟蹤與通信技術研究所,北京100094

摘　要:首先給出時域頻率穩定性分析中各種方差的實用計算公式，并在此基礎上分析各種方差特性，總結歸納其適用范圍。分析表明：①阿侖方差是時域頻率穩定性分析中最常用的方法，但不能區分調相白噪聲和調相閃變噪聲；②改進阿侖方差通過相位平滑運算能識別這2種噪聲；③時間方差和時間總方差主要用于描述頻率源的時間波動，主要用于分析調相噪聲；④當頻率漂移項較大或受甚低頻噪聲影響時，哈達瑪系列方差能給出很好的測量特性。[著者文摘]

關鍵詞:原子鐘 頻率穩定性 置信區間 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