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arXiv · 2507.04040

CSI-Free Symbol Detection for Atomic MIMO Receivers via In-Context Learning

Zihang Song·Qihao Peng·Pei Xiao·Bipin Rajendran·Osvaldo Simeone
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Abstract

Atomic receivers based on Rydberg vapor cells as sensors of electromagnetic fields offer a promising alternative to conventional radio frequency front-ends. In multi-antenna configurations, the magnitude-only, phase-insensitive measurements produced by atomic receivers pose challenges for traditional detection methods. Existing solutions rely on two-step iterative optimization processes, which suffer from cascaded channel estimation errors and high computational complexity. We propose a channel state information (CSI)-free symbol detection method based on in-context learning (ICL), which directly maps pilot-response pairs to data symbol predictions without explicit channel estimation. Simulation results show that ICL achieves competitive accuracy with {higher computational efficiency} compared to existing solutions.

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Zihang Song, Qihao Peng, Pei Xiao, Bipin Rajendran, Osvaldo Simeone. 2025-07-05. CSI-Free Symbol Detection for Atomic MIMO Receivers via In-Context Learning. https://arxiv.org/abs/2507.04040

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