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arXiv · 2606.21012

Asynchronous Multi-Channel USF: Modified CRT for Modulo Unfolding

Ruiming Guo·Ayush Bhandari
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Abstract

The Unlimited Sampling Framework (USF) overcomes the traditional trade-off between dynamic range and digital resolution, achieving performance unattainable with standard ADCs. Its multi-channel extension (MC-USF) enables reconstruction from multiple folded measurements at critical sampling rates. Existing MC-USF methods typically rely on Chinese Remainder Theorem (CRT)-based unfolding, which requires strict channel-level sampling synchronization and is therefore vulnerable to timing mismatch, jitter, and drift. This paper introduces an asynchronous MC-USF architecture that eliminates the need for synchronization. By viewing spatial-temporal signal lifting as inducing smoothness over a graph of sensing channels, we develop a reconstruction strategy robust to temporal misalignment. Numerical experiments validate the approach, demonstrating accurate recovery and enabling more practical multi-channel USF implementations.

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Ruiming Guo, Ayush Bhandari. 2026-06-19. Asynchronous Multi-Channel USF: Modified CRT for Modulo Unfolding. https://arxiv.org/abs/2606.21012

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