Acquisition and scoring
Systèmes de liaisons spatiales par lasers

The two terminals must periodically locate each other, align with a high degree of angular accuracy, and remain in this configuration for as long as possible (usually the duration of one orbit's visibility). This paragraph describes the methods of acquisition (mutual registration of the two optical terminals) and tracking (maintaining mutual alignment). The terminals can be GEO, GEO/LEO or LEO only, or even distant probes communicating with the Earth or a GEO, but we are only interested here in a link between LEO and GEO (which corresponds to the Silex mission).