Assessing Radiation Impact on Chip-Scale Atomic Clocks (CSAC) and Rubidium Clocks

The demand for rapid deployment of smaller, cost-effective satellites in Low and Medium Earth Orbit (LEO and MEO) constellations has driven the need to evaluate low Size, Weight, and Power (SWaP) atomic clocks as on-board frequency and timing references. This study examines the suitability of Chip-Scale Atomic Clocks (CSAC) and rubidium clocks for space applications, where exposure to ionizing radiation presents significant reliability challenges and traditional space-qualified atomic clocks are unsuitable due to high SWaP constraints. The performance and resilience of these clocks under Total Ionizing Dose (TID) radiation, emulating space conditions, are analyzed with a focus on frequency stability, power consumption and phase noise characteristics. The results highlight the extent of degradation and potential failure modes which provides valuable insight into the design considerations and mitigation strategies necessary to ensure the reliability of CSAC and rubidium oscillators in space environments.