Near-Sun free-space optical communications from space

Free-space optical communications offers expanded data return capacity, from probes distributed throughout the solar system and beyond. Space-borne and Earth-based optical transceivers used for communicating optically, will periodically encounter near-Sun pointing. This will result in an increase in the scattered background-light flux, often contributing to degraded link performance. The varying duration of near-Sun pointing link operations relative to the location of space-probes, is discussed in this paper. The impact of near-Sun pointing on link performance for a direct detection photon-counting communications system is analyzed for both ground- and space-based Earth receivers. Finally, the impact of near-Sun pointing on space-borne optical transceivers is discussed