Cold Atom Interferometry Accelerometers for Future Satellite Gravity Missions

Satellite gravity missions are a powerful tool to measure the global Earth’s gravity field and consequently provide important information for geosciences. However, improvements in spatial and temporal resolution are required for many applications. Simulation studies are performed to quantify the influence of improved sensors, orbit parameters and measurement concepts on the recovered gravity field solution. The investigations focus primarily on accelerometers by evaluating the concept of Cold Atom Interferometry (CAI) accelerometers and their combination with electrostatic accelerometers for future satellite gravity missions. The CAI noise behavior is mainly estimated based on the quantum projection noise, but also challenges due to the longer duration of the measurement cycle are investigated. The results of the low-low Satellite-to-Satellite Tracking (ll-SST) closed-loop simulations indicate, on the one hand, benefits from the addition of CAI and reveal, on the other hand, the dominance of background modeling errors. Furthermore, the combination of ll-SST and cross-track gradiometry is studied. In order to significantly benefit from an additional cross-track gradiometer, it has to achieve a low noise level of 1 mE and the angular velocity measurements have to ensure high accuracies. We acknowledge the support by the Deutsche Forschungsgemeinschaft (DFG, German Research Foundation) – Project-ID 434617780 – SFB 1464 and under Germany’s Excellence Strategy – EXC-2123 Quantum-Frontiers – 390837967, the support by Deutsches Zentrum für Luft- und Raumfahrt e.V. (DLR) for the project Q-BAGS and the European Union for the project CARIOQA-PMP (Project-ID 101081775).