On Optical Satellite Communication Systems Design: CFLOS Calculation and OGS Selection

Optical satellite communication systems are severely affected by the cloud coverage. Therefore, for the evaluation of system's availability Cloud Free Line of Sight statistics of the optical ground stations (OGSs) must be estimated. The elevation angles and the altitude of the OGSs should be considered for the accurate prediction and reliable evaluation of the optical satellite network performance. In this paper, new simple engineering expressions for the estimation of CFLOS in terms of the elevation angle of the slant path, the altitude of the OGS, and the CFLOS of the corresponding vertical link are presented. Additionally, a new selection algorithm of the OGSs for the formation of an OGS Network (OGSN) that would achieve a CFLOS threshold but also mitigating the turbulence effects, is proposed. The proposed models are evaluated numerically and some interesting conclusions are drawn.