journal article·2025-10-29Open access

Moving Colorable Graphs: A Mobility-Aware Traffic Steering Framework for Congested Terrestrial–Sea–UAV Networks

Anastasios Giannopoulos, Sotirios Spantideas

Applied Sciences· Volume 15· Issue 21

Abstract

Efficient spectrum allocation and telecom traffic steering in densified heterogeneous maritime communication networks remains a critical challenge due to user mobility, dynamic interference, and congestion across terrestrial, aerial, and sea-based transmitters. This paper introduces the Moving Colorable Graph (MCG) framework, a dynamic graph-theoretical representation of interferences that extends conventional graph coloring to capture the spatiotemporal evolution of heterogeneous wireless links under varying channel and traffic conditions. The formulated spectrum allocation problem is inherently non-convex, as it involves discrete frequency assignments, mobility-induced dependencies, and interference coupling among multiple transmitters and users, thus requiring suboptimal yet computationally efficient solvers. The proposed approach models resource assignment as a time-dependent coloring problem, targeting to optimally support users’ diverse demands in dense port-area networks. Considering a realistic port-area network with coastal, sea and Unmanned Aerial Vehicle (UAV) radio coverage, we design and evaluate three MCG-based algorithm variants that dynamically update frequency assignments, highlighting their adaptability to fluctuating demands and heterogeneous coverage domains. Simulation results demonstrate that the selective reuse-enabled MCG scheme significantly decreases network outage and improves user demand satisfaction, compared with static, greedy and heuristic baselines. Overall, the MCG framework may act as a flexible scheme for mobility-aware and congestion-resilient resource management in densified and heterogeneous maritime networks.
Source: crossref · Quality: baseline

Research context

OpenAlex topics: UAV Applications and Optimization · Satellite Communication Systems · Advanced Wireless Communication Technologies

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Department of Ports Management and Shipping, National and Kapodistrian University of Athens, Evripus Campus, 34400 Euboea, Greece

Research & Development Department, Four Dot Infinity (FDI), Kifisias Avenue, Chalandri, 15231 Athens, Greece

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