Optimization of Active Reconfigurable Surfaces for Spatiotemporal MU-MIMO Wave Routing in Disordered Media: Application to the Cocktail-Party Problem

Frederic J. N. Jorgensen; Florent Dorlot; Constant Bourdeloux; Mathias Fink; Fabrice Lemoult; Steven G. Johnson; Raphaël Pestourie

arXiv · 2610.14328

Optimization of Active Reconfigurable Surfaces for Spatiotemporal MU-MIMO Wave Routing in Disordered Media: Application to the Cocktail-Party Problem

Frederic J. N. Jorgensen·Florent Dorlot·Constant Bourdeloux·Mathias Fink·Fabrice Lemoult·Steven G. Johnson·Raphaël Pestourie

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Abstract

We design an active reconfigurable intelligent surface (RIS) for acoustic multi-user multiple-input multiple-output (MU-MIMO) communication by solving a large-scale convex optimization problem, so that each emitter's broadband signal focuses in space and time at its intended receivers while crosstalk is suppressed. In acoustic experiments, we show that our approach outperforms existing time-reversal methods by 5.1-7.6 dB in crosstalk suppression, while achieving better temporal focusing.

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Frederic J. N. Jorgensen, Florent Dorlot, Constant Bourdeloux, Mathias Fink, Fabrice Lemoult, Steven G. Johnson, Raphaël Pestourie. 2026-10-09. Optimization of Active Reconfigurable Surfaces for Spatiotemporal MU-MIMO Wave Routing in Disordered Media: Application to the Cocktail-Party Problem. https://arxiv.org/abs/2610.14328

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