Different Variances Used for Analyzing the Noise Type of Atomic Clock
Stability is an important factor to measure the quality of an atomic clock. The random factor that affects atomic clock includes five kinds of noise. The random noise can be expressed by spectral density function. In a certain smooth time, only one or two types of noise can influence the atomic clock’s stability. Through the relationship between spectral density function and atomic clock stability analysis variance, such as Allan variance, it’s possible to distinguish the kind of noise on different smooth time. When lacking of data, there is a way that can increase the amount of data by mapping extensions, and it can also improve the degree of confidence in the larger smooth time.
J. Zhai et al., "Different Variances Used for Analyzing the Noise Type of Atomic Clock", Applied Mechanics and Materials, Vols. 229-231, pp. 1980-1983, 2012