Scoping Requirements for a Drag-free System for Next Generation Gravity Field Missions

Abstract:

Studies have shown that next generation gravity field mission architectures taking advantage of laser interferometric ranging and GOCE-type drag-free compensation will be limited by temporal aliasing errors (i.e undersampling and mismodeling of high frequency geophysical signals). In this study, we seek to define the required performance requirements for the removal of non-conservative forces (through drag-free compensation and/or measurement with an accelerometer) such that the high precision laser interferometry measurements can be fully exploited in light of temporal aliasing errors and their uncertainty. The performance requirements are derived via a matrix of high fidelity numerical simulations of the satellite system at various altitudes and for single and dual-pair mission architectures. Expected science outcomes are additionally presented.