First free space optical communication in europe between SOTA and MeO optical ground station

A first free space optical communication campaign was established during June-October 2015 between the NICT SOTA [1], [2] (Small Optical TrAnsponder) instrument flying on the Low Earth Orbit satellite SOCRATES and the Optical Ground Station (OGS) MeO belonging to Observatoire de la Côte d'Azur (OCA) - GeoAzur. Several links at 10 Mbps have been done at 1549 and 976 nm. The main objectives of this experiment are the study of the laser beam propagation through the atmosphere and the design of all the sub-systems constituting the OGS. This experiment has been developed in the framework of an agreement signed between the Japan's National Institute of Information and Communications Technology (NICT) and the French space agency (CNES). The development of the OGS and the measurement campaign were conducted in collaboration with NICT, CNES, ONERA and OCA. The OGS was specially designed for that optical link with SOTA from the existing MeO laser station (primary devoted to satellite and Moon laser ranging). We will first give a global presentation of the whole OGS with some details on the transmitter, the telescope, the receiver bench and the dedicated instrumentation used to monitor the link. We will then give an overview of some results obtained during that campaign.