用Fokker-planck方程对量子频标伺服环跳周的分析  

Analysis of the Cycle-slipping of the Servo-loops in Quantum Frequency Standard with Fokker-planck Equation

作　　者：何强 

机构地区：[1]中国科学院武汉物理研究所

出　　处：《陕西天文台台刊》1992年第1期38-41,共4页Publications of The Shaanxi Astronomical Observatiory

摘　　要：运用Fokker—planck方程对主动型量子频标伺服环的非线性进行了分析,求出了伺服环跳周的平均时间,计算了从初始相位φ_n(0)=0的起始点开始,经过时间T后,出现一次失锁的概率。Using the Fokker-planck equation, we have analysed the nonlinear behavior of the servo-loops in the active quantum frequency standard, also derived the average time of the cycle slipping of the servo-loops and calculated the probability of occurring one time of locking-loss, P(T), for the time interval T, starting from initial point of zero phase. It is well know that practical quantum frequency standards generally include a basic oscillator with a cardinal frequency, which locked to the atomic resonance through a servo loop. For the active quantum frequency standards such as the Hydrogen maser and the Rubidium maser, the atomic ensemble gives out a signal and the phase of the crystal oscillator is locked to the phase of this signal (phase-locked loop). In the servo loops of the active quantum frequency standard, there is a sinusoidal phase detector and it's characteristic is nonlear. Using the Fokker-planck equation, we obtain the following nonlinear differential equation, which govern the probability function P(φ_n, t) : P(φ_n, t)/tφ_n[a K^2N_0/4 sinφ_n(t)P(φ_n, t)+K^2N_0/4 ~2P(φ_n, t)/2φ_n^2]

关 键 词：频率基准 量子频率标准 伺服环 

分 类 号：TB939[一般工业技术—计量学]