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arXiv · 2604.14208

ML-based approach to classification and generation of structured light propagation in turbulent media

Aokun Wang·Anjali Nair·Zhongjian Wang·Guillaume Bal
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Abstract

We study the classification task of structured-light beams after propagation through a random turbulent medium. The received speckle patterns are generated by numerical simulation of a stochastic paraxial propagation model, and the classification task is formulated over a finite alphabet of 15 OAM source classes. We benchmark intensity and autocorrelation inputs using SimpleCNN and ResNet-18 as classifiers. We also quantify the effect of training-set size and receiver-window misalignment. Since additional propagated samples may be costly to obtain, we develop a class-conditioned diffusion model for generative augmentation of turbulence-degraded intensity images. The main contribution is a spectrum-aware diffusion objective: a pixel-domain loss combined with a Fourier-domain Bregman regularizer designed to preserve high-frequency speckle statistics. We prove that this hybrid objective is consistent with the posterior-mean regression target of the diffusion model and show that generated samples substantially improve low-data classification.

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Aokun Wang, Anjali Nair, Zhongjian Wang, Guillaume Bal. 2026-04-04. ML-based approach to classification and generation of structured light propagation in turbulent media. https://arxiv.org/abs/2604.14208

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