A Vibration Correction Method for Shipborne Atomic Gravimeter Based on Second-Order Coupling Acceleration Transfer Model

The atomic interference gravimeter, characterized by its high sensitivity and precision in gravity measurement, is significantly influenced by vibration noise in field environments. The vibration correction is a feasible approach to mitigate the constraints imposed by vibration noise in measurements, thereby enhancing accuracy. The vibration noise of the shipborne environment is intensified, leading to the complete disruption of the traditional chirp fringes. We analyzed the correlation between the vibration phase and atom population and developed an acceleration phase fringe that is suitable for the shipborne environment. Subsequently, to enhance the precision of calibrating the transfer function resulting from the inconsistency between the centers of the accelerometer mass and the Raman reflecting mirror, we proposed a second-order coupling acceleration transfer model as a substitute for the traditional model. An intelligent optimization algorithm was employed to optimize the model parameters. Finally, an atomic gravimeter system was constructed to assess the proposed model and method in the context of shipborne. The results indicate that the proposed second-order coupling model demonstrates superior calibration efficacy compared to the traditional model. Compared with the uncalibrated, the standard deviation of drift phase residuals shows an average decrease of 87.8%, and the root mean square error (RMSE) of fitting decreases by 53.7%. The improvement in both short-term accuracy and long-term stability of mooring gravity measurement is substantial. The ocean navigation gravimetry shows better repeatability and external consistency. Compared with the uncalibrated, the internal and external coincidence accuracy improved by 93.6% and 92.0%, respectively.