Intelligent reflecting surface (IRS)-assisted wireless communication is widely deemed a key technology for 6G systems. The main challenge in deploying an IRS-aided terahertz (THz) link, though, is the severe propagation losses at high frequency bands. Hence, a THz IRS is expected to consist of a massive number of reflecting elements to compensate for those losses. However, as the IRS size grows, the conventional far-field assumption starts becoming invalid and the spherical wavefront of the radiated waves must be taken into account. In this work, we focus on the near-field and analytically determine the IRS response in the Fresnel zone by leveraging electromagnetic theory. Specifically, we derive a novel expression for the path loss and beampattern of a holographic IRS, which is then used to model its discrete counterpart. Our analysis sheds light on the modeling aspects and beamfocusing capabilities of THz IRSs.
@article{arxiv.2108.08104,
title = {Electromagnetic Modeling of Holographic Intelligent Reflecting Surfaces at Terahertz Bands},
author = {Konstantinos Dovelos and Stylianos D. Assimonis and Hien Quoc Ngo and Boris Bellalta and Michail Matthaiou},
journal= {arXiv preprint arXiv:2108.08104},
year = {2021}
}
Comments
To appear in the 55th Annual Asilomar Conference on Signals, Systems, and Computers, 2021 (invited paper)