Research on TTL Noise Suppression of space gravitational wave detection: Using Modeling the Motion of the Telescope Plane and Adaptive Optical Systems

Abstract As a core technology for space-based gravitational wave detection, intersatellite laser ranging achieves gravitational wave signal capture by precisely measuring the relative distance between test masses in remote and local satellites. However, the complex space gravity-field environment surrounding the detectors can perturb the geodesic motion of test masses within the satellites. For the satellite following the motion of test masses, the space gravity-field environment induces sensitive axis pointing deviations and optical reference offsets of the satellite telescopes, which constitute critical components of tilt-to-length coupling noise (TTL noise). This noise will vary phases and propagates as noise into the range signals of space-based gravitational wave detection, ultimately causing range errors, ultimately degrading intersatellite ranging precision. Based on the TianQin mission, this study conducts numerical simulations of the TTL noise induced by the space gravity-field environment and implements compensation through two approaches: modeling the motion of the telescope plane and adaptive optical system simulations. The simulation results show that the application of modeling the motion of the telescope plane and adaptive optical system simulation methods effectively mitigates phase noise caused by TTL noise, providing innovative technical pathways and methodologies for addressing TTL noise in space-based gravitational wave detection.