Methodology for Reconstruction of Shipborne Atom Gravimeter Interference Fringes With Nonlinear Effect Compensation

The integration of atom gravimeters with classical accelerometers has enabled long-term, high-precision dynamic gravity field measurements. Under dynamic conditions, suppressing measurement noise is essential for enhancing measurement performance. To address residual phase noise in atom interference fringe, this article introduces a method for reconstructing atom interference fringes based on the nonlinear inversion of accelerometer data. By precisely calibrating the accelerometer’s transfer function and employing the truncated singular value decomposition (TSVD) method to solve the inversion model, we have successfully inverted the acceleration signals. This process not only reduces errors in the accelerometer’s transfer function but also mitigates measurement errors caused by nonlinear effects. Following shipboard mooring experiments, the reconstructed interference fringes demonstrated a significant improvement in contrast compared to the unmodified fringes. The phase uncertainty of the fitting fringe can be reduced from 5.4037 to 1.183 mGal, while the expanded uncertainty decreases from 10.807 to 2.366 mGal, representing a substantial 78.12% improvement in performance, and fringe contrast increased by 32%. Furthermore, when compared to existing linear calibration models, our method achieved a 17.2% improvement in performance. Compared to other methods, this approach demonstrates superior repeatability and higher internal consistency accuracy in dynamic navigation gravity measurements, thereby enhancing the accuracy and sensitivity of atom dynamic measurements. These findings validate the effectiveness of our improved method and offer a novel approach to noise suppression in atom gravity measurement systems.