The cross-link tecnique for deep space missions

Availability of a precise time reference is a key issue for several space missions. Although atomic clocks already have a good flight experience, they also have heavy requirements in terms of volume, mass, power and cost, which do not fit all applications. An alternative to this solution is the use of a good precision oscillator which shall be synchronized to a ground station master clock. The proposed paper illustrates the findings of a recent study promoted by ESA on in-space synchronization methods. The selected approach is based on the cross-link technique.