Abstract:

Rubidium atomic clock has high reliability, small size and low power consumption.It is widely used in the fields of navigation, communication, etc.Especially for rubidium atomic clocks for navigation satellites, they have excellent stability performance so far, but their inherent frequency drift characteristics (about E-12 to E-13/day) will deteriorate their long-term performance and affect the autonomous operation ability of satellites.In this paper, the frequency data of high-performance rubidium atomic clocks are fully analyzed, the physical mechanism that may lead to frequency drift is studied, and a model for compensating for frequency drift with high accuracy is proposed and experimental verification is carried out.The results show that the drift rate of the high-performance rubidium clock can be maintained in the order of E-15/day within 60 days without external taming, and the day stability can reach the order of E-15 (Allan variance), which greatly improves the autonomous punctuality ability of rubidium atomic clock．

Key words: Rubidium atomic clock, Frequency drift, Frequency drift compensation, Autonomous punctuality