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arXiv · 2605.31549

Microwave Linear Analog Computer (MiLAC) for Simultaneous Active and Passive Beamforming

Matteo Nerini·Bruno Clerckx
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Abstract

Microwave linear analog computers (MiLACs) have recently emerged to enable high-performance and efficient beamforming in the analog domain. In this paper, we introduce a dual-functionality framework for MiLAC-aided transceivers. Beyond analog-domain precoding/combining (active beamforming), a MiLAC and its antenna array can simultaneously act as a reconfigurable intelligent surface (RIS) (passive beamforming). This allows the MiLAC to execute beamforming for transmission/reception while reflecting external incident signals. We provide an optimal reconfiguration strategy for this dual-functional MiLAC, and characterize the fundamental limits on the trade-off between active and passive rate, namely the capacity region bounds and the sum-rate capacity.

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Matteo Nerini, Bruno Clerckx. 2026-05-29. Microwave Linear Analog Computer (MiLAC) for Simultaneous Active and Passive Beamforming. https://arxiv.org/abs/2605.31549

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