26-221 Atmospheric turbulence prediction for optical links optimization

Mission

High-speed optical communications for satellite data have been under study for several years; they offer a good alternative to radio frequency (RF) links which are approaching the limit of their capacities in terms of data rate. Indeed, the motivation of optical space communication systems stems from the fact that higher data rates (10 times) than RF solutions could be achievable with similar on-board terminal loads.

The Observatoire de la Côte d'Azur (OCA), via its MéO laser station on the Calern plateau, is involved in several projects implementing high-performance ground-space optical links.

The limiting factor of this kind of links is the atmospheric turbulence. Indeed, fluctuations of the refractive index of air cause fluctuations in the phase and amplitude (scintillation) of the wavefront. These sometimes very high disturbances can cause the loss of the signal and generally make the link budget weak.

The OCA observation site, Ca...