Wideband Coverage Enhancement for IRS-Aided Wireless Networks Based on Power Measurement

TL;DR

This paper introduces a power-measurement-based method to enhance wideband coverage in IRS-aided wireless networks, reducing the need for frequent channel reconfiguration and improving average channel gain.

Contribution

It proposes a novel approach to estimate channel autocorrelation matrices using power measurements, enabling coverage enhancement without extensive channel estimation overhead.

Findings

Improved average coverage performance demonstrated through simulations.

Effective channel autocorrelation estimation using power measurements.

Reduced IRS reconfiguration frequency while maintaining coverage quality.

Abstract

By applying tunable phase shifts to incident waves via passive signal reflection, intelligent reflecting surface (IRS) can offer significant performance improvement for wireless communication systems. To reap such performance gain, channel knowledge for IRS-cascaded links is generally required, which is practically challenging to acquire due to their high-dimensional and time-varying characteristics. Conventional pilot-based channel estimation incurs excessive overhead due to the large number of reflecting elements, thus undermining the IRS efficiency, especially for wideband systems with frequency-selective fading channels. To tackle this issue, we propose in this letter a power-measurement-based channel autocorrelation matrix estimation and coverage enhancement approach for IRS-aided orthogonal frequency division multiplexing (OFDM) systems. Specifically, by estimating equivalent channel autocorrelation matrices of IRS-cascaded OFDM channels based on receive signal power and optimizing the IRS reflection vector based on them, the average coverage performance in the IRS-aided region is enhanced without the need for frequent reconfiguration of IRS reflection coefficients based on user instantaneous channels. Simulation results validate the effectiveness of the proposed approach for improving the average channel gain over the coverage region.