Beam pointing error as a significant design parameter for satellite-borne, free-space optical communication systems

The issue of pointing errors between satellite-borne, free-space optical communication systems is examined. The single-axis pointing error distribution is described as a Gaussian function and is used to define a probability of burst error for the pointing subsystem. A relationship between the rms standard deviation of the pointing error distribution, the probability of burst error, and the Airy far field beamwidth is deduced. It is shown that the system beamwidth and antenna diameter are limited by the probability of burst error. Additionally, it is found that typical terminal designs have less temporal communication system availability than one specifically designed to account for the influence of burst errors.