Wideband Synthetic Aperture Test Bed for Intelligent Reflecting Surfaces.

This paper describes a spherical beamforming implementation for wideband synthetic aperture channel sounders that can be used to predict the scattering performance of an Intelligent Reflection Surface (IRS). An IRS creates controlled propagation conditions in wireless channels that can amplify the signal power available at a receiver or can enhance communications security by reducing the signal leaking to an eavesdropper. Most IRS performance evaluations described in the technical literature to date rely on simulation and modeling approaches. These techniques necessarily produce idealized results that neglect the impact of real-world multipath. However, by incorporating wireless channel measurements taken by a synthetic aperture into a spherical beamforming framework, the detrimental effects of environmental multipath on the signal reflected from an IRS can be realistically accounted for.