原子钟相位与频率估计的误差特性

Analysis of Estimation Error in Atomic Clock Phase and Frequency

本文讨论了原子钟内部的３种噪声即白色调相噪声、白色调频噪声和随机游走调频噪声对相位和频率估计的影响。分析表明，这３种噪声对相位估计和频率估计的影响完全不同。在相位估计中，选择适当的平滑长度和取样间隔可以控制估计误差；而在频率估计中，估计精度不能通过估计器或测量设备的改进而任意提高，存在一个极限，这个极限由原子钟的内部噪声来决定。

Estimations of atomic clock phase and frequency are compared in this paper. Due to the effects of clock internal noise processes, the errors of these two estimations are quite different. In phase estimation, the error can be reduced by properly selected smoothing length and sampling interval. But in frequency estimation, the error can not be reduced arbitrarily by means of improving the estimator or measuring equipment. The precision of frequency estimation is limited by the intrinsic noise in the clock.