On Vehicular Ad-Hoc Networks With Full-Duplex Radios: An End-to-End Delay Perspective

• Published in: IEEE transactions on intelligent transportation systems 2023-10, Vol.24 (10), p.1-11
• Main Authors: Zhou, Momiao, Liu, Lei, Sun, Yanshi, Wang, Kan, Dong, Mianxiong, Atiquzzaman, Mohammed, Dustdar, Schahram
• Format: Article
• Language: English
• Subjects: deep Q network (DQN); Delay; Dijkstra's algorithm; full-duplex; Mobile ad hoc networks; Network topologies; Routing; Routing (telecommunications); vehicular ad-hoc network (VANET)
• ISSN: 1524-9050; 1558-0016
• DOI: 10.1109/TITS.2023.3279322

The aim of this paper is to present a groundwork on the delay-minimized routing problem in a vehicular ad-hoc network (VANET) where some of the vehicles are equipped with full-duplex (FD) radios. We first give the generalized delay calculation model for a multi-hop path, and prove that the Dijkstra algorithm is unable to get the delay-minimized routing path from source to destination. Then we propose two routing methods: graph-based method and deep reinforcement learning (DRL)-based method. In the graph-based method, the network topology is reformulated as an equivalent graph and then an evolved-Dijkstra algorithm is proposed. In the DRL-based method, the deep Q network (DQN) is employed to learn the shortest end-to-end path, wherein the delay is modeled as the rewards for routing actions. The graph-based method can achieve the exact minimum end-to-end delay, while the DRL-based method is more feasible due to its acceptable complexity. Finally, extensive simulations demonstrate that the DRL-based approach with proper hyper-parameters can achieve near minimum end-to-end delay, and the achieved delay has a notably decline as the number of FD nodes increases.