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arXiv · 2607.12494

Estimation of the laser guide star uplink tip-tilt using aperture size diversity

Pierre Jouve·Thierry Fusco·Carlos M. Correia·Cédric Taissir Heritier·Jean-François Sauvage·Benoit Neichel
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Abstract

Laser guide star (LGS) adaptive optics cannot directly measure tip-tilt (TT), forcing reliance on natural guide stars and limiting sky coverage. We propose estimating the uplink TT from telemetry acquired at the laser launch telescope alone, operated in a monostatic configuration as both emitter and receiver. Extracting TT over concentric disks of different diameters within the receiving pupil yields signals mixing uplink and downlink contributions in different proportions; this aperture size diversity, combined with an LMMSE estimator, disentangles the uplink component. Simulations show a residual error of 24 mas for a single turbulent layer and 34 mas with two layers.

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Pierre Jouve, Thierry Fusco, Carlos M. Correia, Cédric Taissir Heritier, Jean-François Sauvage, Benoit Neichel. 2026-07-14. Estimation of the laser guide star uplink tip-tilt using aperture size diversity. https://arxiv.org/abs/2607.12494

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