AoI-Aware Spectrum and Power Allocation for High-Speed Railway Networks
Difei Jia, Fengye Hu, Zhuang Ling, Zhi Juan Mao, Zheng Chang, Timo Hämäläinen · 2022
This paper studies a high-speed railway (HSR) network, where train-to-infrastructure (T2I) and train-to-train (T2T) transmissions co-exist. First, we analyze the age of information (AoI) of the T2T link to capture the freshness of data. Then, with the objective to maximize the sum data rate of T2I links, we formulate a resource allocation optimization problem subject to the data rate constraint of T2I links and the average AoI constraint of T2T links. Since the formulated problem has coupled optimizing variables and non-convex structure, we propose an AoI-aware spectrum and power allocation (AoI-ASPA) scheme to address it. In the proposed scheme, the optimization problem is decomposed into a power allocation subproblem and a spectrum allocation subproblem, and solved in two steps. For the power allocation subproblem, the optimal power allocation solution for each spectrum reusing pair is derived in an algebraic method. For the spectrum allocation subproblem, we transform it into a weighted bipartite matching problem and solve it by using the Kuhn-Munkres (KM) method. Simulation results verify the effectiveness of our proposed scheme.