Optimized phase shifts in intelligent reflective surfaces for robust radar-based indoor coverage enhancement

Abstract

Intelligent reflective surfaces (IRS) have garnered significant attention due to their potential to intelligently shape the wireless environment for beyond-fifth and sixth-generation wireless communication and sensing. IRSs modify radio channels by dynamically adjusting the phase shifts of reflected signals, thereby enhancing signal reception and suppressing interference. For robust beam steering and signal-to-noise ratio optimization, the IRS’s phase profile must be accurately estimated and optimized. This work presents a unique approach for estimating the position and orientation of an indoor IRS using active tags and optimizing the phase shifts with a tag-FMCW radar system for robust radar-based IRS-assisted indoor coverage enhancement. The proposed method offers a practical scheme for localizing the IRS elements and calculating the phase delays effectively, ultimately improving the overall performance of IRS-assisted wireless networks. For implementation, we proposed non-volatile phase-change radio-frequency switches that can operate over a broad range and can provide flexibility in implementation from DC to 67 GHz for 5G-Advanced applications.