학술논문

Multi-IRS-Aided Terahertz Networks: Channel Modeling and User Association With Imperfect CSI
Document Type
Periodical
Source
IEEE Open Journal of the Communications Society IEEE Open J. Commun. Soc. Communications Society, IEEE Open Journal of the. 5:836-855 2024
Subject
Communication, Networking and Broadcast Technologies
Array signal processing
Signal to noise ratio
Resource management
Wireless networks
Transmitters
Receivers
MIMO communication
Intelligent reconfigurable surface (IRS)
matching theory
optimization
terahertz (THz)
Language
ISSN
2644-125X
Abstract
Terahertz (THz) communication is envisioned as one of the candidate technologies for future wireless communications to enable achievable data rates of up to several terabits per second (Tbps). However, the high pathloss and molecular absorption in THz band communications often limit the transmission range. To overcome these limitations, this paper proposes intelligent reconfigurable surface (IRS)-aided THz networks with imperfect channel state information (CSI). Specifically, we present an angle-based trigonometric channel model to facilitate the performance evaluation of IRS-aided THz networks. In addition, to maximize the sum rate, we formulate the transmitter (Tx)-IRS-receiver (Rx) matching problem, which is a mixed-integer nonlinear programming (MINLP) problem. To address this non-deterministic polynomial-time hard (NP-hard) problem, we propose a Gale-Shapley algorithm-based solutions to obtain stable matching between transmitters and IRSs, and receivers and IRSs, in the first and second sub-problems, respectively. The impact of the transmission power, the number of IRS elements, and the network area on the sum rate are investigated. Furthermore, the proposed algorithm is compared to an exhaustive search, nearest association, greedy search, and random allocation to validate the proposed solution. The complexity and convergence analysis demonstrate that the computational complexity of our algorithm is lower than that of the ES method.