An Experimental Assessment of the Spatial and Frequency Selectivity of Reconfigurable Intelligent Surfaces

2026-06-25

AI Summary

This study reveals that reconfigurable intelligent surfaces (RIS), while optimizing a primary communication link, can induce significant unintended interference on nearby secondary links—even when the two are spatially separated and operate on distinct carrier frequencies. Through real-world experiments conducted in the FR1 band using the CorteXlab platform and Greenerwave RIS hardware, the work systematically evaluates the impact of RIS configurations on the received power and channel phase of secondary links under representative coexistence scenarios, including both co-channel and inter-channel conditions. The experiments provide the first empirical evidence that conventional assumptions relying on frequency-domain isolation to mitigate interference no longer hold in RIS-enabled environments, thereby underscoring the critical need for cross-link compatibility considerations in RIS deployment strategies.

Abstract

This work investigates the impact of reconfigurable intelligent surfaces (RIS) on radio links other than the one for which the RIS configuration is optimized. We consider three different scenarios in which a secondary communication link could be affected by a RIS whose configuration is optimized for a primary communication link operating in the vicinity, on the same or on different frequencies. This question is investigated experimentally in the FR1 band, using the CorteXlab radio testbed and a Greenerwave RIS. We show that the impact, in terms of received power and impact on the channel phase of the secondary link, is significant even outside of the nominal frequency range of the RIS, and is not mitigated by carrier frequency separation between the two communication links.

Problem

• Reconfigurable Intelligent Surfaces
• spatial selectivity
• frequency selectivity
• interference
• secondary communication link

Innovation

• Reconfigurable Intelligent Surfaces
• spatial selectivity
• frequency selectivity
• cross-link interference
• experimental assessment