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arXiv · 2601.13769

Interoperable rApp/xApp Control over O-RAN for Mobility-aware Dynamic Spectrum Allocation

Anastasios Giannopoulos·Sotirios Spantideas·Maria Lamprini Bartsioka·Panagiotis Trakadas
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Abstract

Open Radio Access Networks (O-RAN) enable the disaggregation of radio access functions and the deployment of control applications across different timescales. However, designing interoperable control schemes that jointly exploit long-term traffic awareness and near-real-time radio resource optimization remains a challenging problem, particularly under dense multi-cell interference and heterogeneous service demands. This paper proposes an interoperable rApp/xApp-driven dynamic spectrum allocation (DSA) framework for O-RAN, based on a graph-theoretic formulation of physical resource block (PRB) assignment. The proposed architecture leverages a non-real-time radio intelligent controller (Non-RT RIC) rApp to predict aggregated traffic evolution and generate high-level spectrum policies at the minutes timescale, while a near-real-time RIC (Near-RT RIC) xApp constructs a user-centric conflict graph and performs fairness-aware PRB allocation at sub-second timescales. To mitigate persistent user starvation, a conflict-aware modified proportional fair (MPF) scheduling mechanism is applied, enabling controlled interference-free PRB time-sharing. Extensive simulation results demonstrate that the proposed framework significantly improves the PRB assignment success rate (above 90%) and service-share fairness (above 85%) across different channel configurations and user demands, while maintaining architectural separation and rApp/xApp interoperability in accordance with O-RAN principles.

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Anastasios Giannopoulos, Sotirios Spantideas, Maria Lamprini Bartsioka, Panagiotis Trakadas. 2026-01-20. Interoperable rApp/xApp Control over O-RAN for Mobility-aware Dynamic Spectrum Allocation. https://arxiv.org/abs/2601.13769

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