Adaptive optics requirements for a ground-to-space laser communications system

Advances in adaptive optics have made it possible to consider their use to enhance ground-to-space laser communications systems. Adaptive optics are used to counteract the effects of atmospheric turbulence and deliver a beam undistorted through the atmosphere. This paper examines the system level requirements of an adaptive optical system in terms of communication parameters. An optical communications link must deliver a modulated beam to a receiving sensor with minimal distortion of the modulated signal. Distortion which stretches pulses, distorts pulse shapes, or otherwise randomizes the pulse intensity or location contributes to a higher bit error rate. The ability of adaptive optics to compensate for atmospheric scintillation is studied with respect to its effect on signal fade and surge.