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arXiv · 2407.04745

Optimal design of small aperture optical terminals for free-space links

Alex M. Frost·Benjamin P. Dix-Matthews·Shane M. Walsh·David R. Gozzard·Sascha W. Schediwy
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Abstract

We present the generalised design of low-complexity, small aperture optical terminals intended for kilometre-scale, terrestrial, free-space laser links between fixed and dynamic targets. The design features single-mode fibre coupling of the free-space beam, assisted by a fast-steering, tip/tilt mirror that enables first-order turbulence suppression and fine target tracking. The total power throughput over the free-space link and the scintillation index in fibre are optimised. The optimal tip/tilt correction bandwidth and range, aperture size, and focal length for a given link are derived using analytical atmospheric turbulence modelling and numerical simulations.

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Alex M. Frost, Benjamin P. Dix-Matthews, Shane M. Walsh, David R. Gozzard, Sascha W. Schediwy. 2024-07-04. Optimal design of small aperture optical terminals for free-space links. https://arxiv.org/abs/2407.04745

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