High-Precision Digital Temperature Control Method for Rubidium Atomic Clocks

Rubidium atomic clocks' frequency stability and accuracy are highly sensitive to lamp and cavity temperature fluctuations. To address limitations of conventional analog control and digital PID control, this study proposes a high-precision digital temperature control method based on second-order system modeling and PI control. Equivalent models are established, parameters are quantitatively determined via heater gain calibration, and an integral limiting strategy is adopted. Experiments show steady-state temperature fluctuations of ±0.04 °C (lamp) and ±0.02 °C (cavity), enabling fast, accurate, and stable regulation without empirical tuning, improving clock performance and providing a reliable solution for precision temperature control.