Time Transfer From GPS for Designing a SmallSat-Based Lunar Navigation Satellite System

Abstract For the future lunar navigation satellite system (LNSS), a GPS-like constellation for Moon, NASA has expressed interest in using smallsat platform. However, many design decisions have yet to be finalized, including orbit, constellation, and onboard clock. Furthermore, designing dedicated smallsat-based LNSS limits payload capacity, thus restricting size, weight, power (SWaP) of We propose an with time transfer from intermittently available GPS signals wherein we Kalman filter estimate timing corrections low-SWaP Additionally, devise User Equivalent Range Error (UERE) metric characterize ranging accuracy transmitted by satellite. further validate our time-transfer technique simulations elliptical frozen orbit (ELFO) chip scale atomic clock (CSAC) while analyzing visibility effects GPS, errors, UERE across ELFOs.