A hybrid stabilization approach for deep-space optical communications terminals

Near-Earth laser communication system designs typically use the near-symmetric power levels in duplex links as bright sources upon which to base active beam stabilization. In deep space, it may be difficult to provide a constant, high-power laser beacon as a stabilization reference. we describe here several means, aimed at different frequency ranges of control, for generating a combined pointing reference and for actively controlling beam position. Such a blended approach gives a highly flexible system for performing beam stabilization in deep space, where distances, conditions, and power levels can vary widely.