A.G. Artemov, V.N. Grigoriev

The Sun within the field of view of the telescopes of optical communication systems may cause dramatic increase in the noise level, breaking up the data transfer. As simulator study shows, the main orbital parameter determining the possible downtime of a system for a LEO-GEO link is the longitude of ascending node of the LEO satellite. The minimum solar illumination both during the year and during the communication contact lies in the longitude range of 50-70 degrees.