Performance analysis of a multiple-input-single-output optical satellite communication system with correlated pointing errors

In this study, the performance of multiple-input-single-output optical communication schemes is analysed in the context of inter-satellite communication. The analysis covers two types of diversity schemes: selection combining (SC) and equal gain combining. Outage probabilities with correlated errors are derived. The main results are expressed in terms of the first-order Marcum Q-function. It is shown that the merit of combining is obvious when the correlation coefficient is less than 0.5 and equal gain combining (EGC) has an advantage over SC in power utilisation.