Optimized laser beam parameters for communications in space environments in the presence of pointing errors

Abstract

We investigate the behavior of spatially partially coherent beams (PCBs) in the presence of pointing errors in the space communication environment. Closed form expressions for the optimal coherence length for minimizing outage probability and maximizing average signal-to-noise ratio (SNR) are derived. In the case of outage probablity, we observe that the optimal coherence parameter does not depend on the pointing error statistics. For average SNR results, PCBs can improve performance when large fixed beam offsets are present. We also provide BER performance analysis results for a convolutionally coded system and demonstrate significant performance improvement using PCBs with optimized parameters.