Autonomous Rubidium Clock Weak Frequency Jump Detector for Onboard Navigation Satellite System.

Area of Science:

• Atomic Physics
• Navigation Systems Engineering
• Signal Processing

Background:

• Frequency jumps in rubidium atomic frequency standards are common and impact navigational satellite system accuracy.
• Immediate detection and correction of these jumps are vital for maintaining navigation system integrity.

Purpose of the Study:

• To propose a novel weak frequency jump detector for rubidium atomic frequency standards.
• To enable fast and accurate detection and correction of both sudden and slow frequency transitions.

Main Methods:

• A Kalman filter with a multi-interval approach is employed to reduce clock data noise and estimate jump size with reduced latency.
• Analysis of in-orbit rubidium atomic frequency standard (RAFS) phase telemetry data was performed.
• A multialgorithm-based strategy is proposed for onboard navigation satellites.

Main Results:

• The proposed detector effectively achieves fast detection and correction of weak frequency jumps.
• The Kalman filter enhances the accuracy of jump size estimation and reduces detection latency.
• Performance comparison with existing techniques demonstrates the proposed detector's advantages.

Conclusions:

• The novel weak frequency jump detector offers a robust solution for improving the integrity of navigational satellite systems.
• The multialgorithm strategy optimizes detection based on jump characteristics for onboard applications.
• This research contributes to more reliable positioning in satellite navigation.