Sensor Fusion Error and Spectral Analyses for Airborne Quantum Gravimetry: The AeroQGrav Case Study

Abstract Earth’s gravity field can be reconstructed by adopting several techniques that involve data collected from satellite-, aircraft-, and ground-based measurements. Airborne gravimetry is a powerful tool for remote regions, like mountains or deserts, and for obtaining a higher spatial resolution than satellite gravity measurements. The German Absolute Aero Quantengravimetrie (AeroQGrav) project aims to build an airborne atom interferometer to fill gaps in regional geoid modelling and achieve precisions of down to 1 μm/s 2 after 5 s of signal integration. In this manuscript, starting from the requirements, a spectral analysis of the sensor errors addresses the limiting factors of the project. In the sensor fusion process, separating the kinematic from the gravitational acceleration represents one of the main challenges of airborne gravimetry. Depending on the spatial resolution and frequency domain of interest, the successful achievement of the required measured gravity’s accuracy and precision may be limited by the spectral characteristics of the adopted kinematic sensors. An optimal simulation scenario is adopted to model the sensors and evaluate their noise contribution. Finally, it is presented how to exploit the fusion of the kinematic sensor measurements to retrieve the gravity signal at multiple frequencies of interest and precisions, overcoming the single-sensor limitations.