Autonomous Deep Space Spacecraft Orbit Determination via One-Way Uplink Ranging Observables

Most of space missions rely on measuring two-way range and Doppler observables, which involves timing how long it takes for a radio signal to travel from a ground station to the spacecraft and back. However, this type of navigation becomes less effective as the spacecraft moves further away from Earth, causing significative delays in signal propagation. In this thesis we try to verify if it is possible to enable autonomous spacecraft navigation through a time transfer link in the microwave domain between a ground station, equipped with its highly stable clock, and the spacecraft, outfitted instead with a clock characterised by a lower temporal and frequency stability. This time transfer implies a series of synchronisation windows, at the end of which the spacecraft will show the same time reference as its on-ground counterpart. This type of one-way navigation is crucial for all those critical operations when the signal from Earth would take too long to reach the spacecraft, especially for those space vehicles which travel towards very remote planets. In fact, in this novel paradigm, the ground control can let the spacecraft move along its designed trajectory without taking actions unless some unpredicted problem arises.