QoS-Driven Spectrum Sharing for Reconfigurable Intelligent Surfaces (RISs) Aided Vehicular Networks

Yuanbin Chen (1) , Ying Wang (1) , Jiayi Zhang (2) , Marco Di Renzo (3, 4, 5)

1 BUPT - Beijing University of Posts and Telecommunications
2 BJTU - Beijing Jiaotong University
3 L2S - Laboratoire des signaux et systèmes
4 CNRS - Centre National de la Recherche Scientifique
5 Université Paris-Saclay

Reconfigurable intelligent surfaces (RISs) have the capability of reconfiguring the wireless environment in a favorable way to improve the quality-of-service (QoS) of wireless communications. This makes RISs a promising candidate to enhance vehicle-to-everything (V2X) applications. This paper investigates the spectrum sharing problem in RIS-aided vehicular networks, in which multiple vehicle-to-vehicle (V2V) links reuse the spectrum already occupied by vehicle-to-infrastructure (V2I) links. To overcome the difficulty of acquiring instantaneous channel state information (CSI) due to the fast varying nature of some V2X channels, we rely upon large-scale (slowly varying) CSI in order to fulfill the QoS requirements of V2I and V2V communications. Particularly, we aim to maximize the sum capacity of V2I links that are used for high-rate content delivery and to guarantee the reliability of V2V links that are used for the exchange of safety information. The transmit power of vehicles, the multiuser detection (MUD) matrix, the spectrum reuse of V2V links, and the RIS reflection coefficients are jointly optimized, which results in a mixed-integer and non-convex optimization problem. To tackle this problem, the outage probability of each V2V link is first approximated by introducing an analytical expression to simplify the formulated problem. By leveraging the block coordinate descent (BCD) method, the considered optimization problem is decomposed into three sub-problems, whose optimal solutions are provided independently and updated alternately to obtain a near-optimal solution. Simulation results verify the theoretical analysis and the effectiveness of the proposed algorithm, as well as unveil the benefits of introducing RISs for enhancing the QoS performance of vehicular communications.

Mots clés: Vehicular networks; V2X; reconfigurable intelligent surfaces; QoS; resource allocation

Domaines: Electronique

Yuanbin Chen, Ying Wang, Jiayi Zhang, Marco Di Renzo. QoS-Driven Spectrum Sharing for Reconfigurable Intelligent Surfaces (RISs) Aided Vehicular Networks. IEEE Transactions on Wireless Communications, 2021, 20, pp.5969 - 5985. ⟨10.1109/twc.2021.3071332⟩. ⟨hal-03377240⟩