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NASA NTRS · 20170011077

Distributed Timing and Localization (DiGiTaL)

D'Amico, Simone·Hunter, Roger C.·Baker, Christopher
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Abstract

The Distributed Timing and Localization (DiGiTaL) system provides nano satellite formations with unprecedented,centimeter-level navigation accuracy in real time and nanosecond-level time synchronization. This is achieved through the integration of a multi-constellation Global Navigation Satellite System (GNSS) receiver, a Chip-Scale Atomic Clock (CSAC), and a dedicated Inter-Satellite Link (ISL). In comparison, traditional single spacecraft GNSS navigation solutions are accurate only to the meter-level due to the sole usage of coarse pseudo-range measurements. To meet the strict requirements of future miniaturized distributed space systems, DiGiTaL uses powerful error-cancelling combinations of raw carrier-phase measurements which are exchanged between the swarming nano satellites through a decentralized network. A reduced-dynamics estimation architecture on board each individual nano satellite processes the resulting millimeter-level noise measurements to reconstruct the fullformation state with high accuracy.

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D'Amico, Simone, Hunter, Roger C., Baker, Christopher. 2017-08-05. Distributed Timing and Localization (DiGiTaL). https://ntrs.nasa.gov/citations/20170011077

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