A Study on the Role of High-Low Satellite-to-Satellite Tracking (SST) in Combination with Low-Low SST for Gravity Field Estimation

<p>Satellite gravimetry missions continue to provide data to produce high resolution gravity models of the Earth for over 20 years. The Gravity Recovery and Climate Experiment Follow-On (GRACE-FO) exemplifies the current state-of-the-art mission architecture. GRACE-FO consists of a pair of twin satellites flying in the same orbit with an onboard laser ranging interferometer (LRI) system and GNSS receivers. The LRI is used for accurately tracking low-low satellite range change. The GNSS receivers are used for high-low SST to GNSS satellites, contributing information for satellite positioning, timing, and long-wavelength gravity field information.&#160;</p><p>We present results from a numerical simulation study to assess possible variations of the high-low component of the architecture relative to the GRACE-FO configurations. Aspects of the setup such as measurement observables, measurement and bias parameterization, and noise characteristics are evaluated to fully characterize how high-low SST and its errors impact gravity field estimation. We anticipate the results to be useful in the architecture and science data analysis algorithms for future mass change missions.&#160;</p>