Research on noise suppression of inter-satellite laser pointing jitter

Abstract

In the Taiji mission, since the transmission distance of the inter-satellite laser link reaches three million kilometers, the wavefront of its laser transmission will be distorted. Therefore, laser interferometric relative distance measurements can be significantly affected by laser-pointing jitter noise. We built a ground verification system based on the Michelson interferometer to verify critical technologies. At the same time, we analyzed the control characteristics of the system from the perspectives of frequency and time domains. In the end, we successfully built the system in the atmospheric environment of the laboratory and carried out related technical verifications. The experimental results show that in the case of 4µrad/√ Hz@10mHz disturbance, the system can suppress the laser pointing jitter noise to 31.2nrad/√ Hz@10mHz (inner ring data) and 385.7nrad/√ Hz@10mHz (outer ring data), and the effect has reached below the noise floor. The experiment promotes the development of pointing system technology based on the Michelson interferometer and provides relevant technical verification for the follow-up Taiji mission.