Distributed Scheduling and Its Asymptotic Analysis for Cognitive Radio Networks Under the Many-Channel Regime

The design of efficient and distributed scheduling algorithms is essential to garner the full potential of cognitive radio networks (CRNs). In this paper, we propose a distributed orthogonal frequency-division multiplexing (OFDM)-based scheduling algorithm, which is called the collision-queue-regulated algorithm, that aims to limit the collision rate to a level imposed by primary users of a CRN. Via a novel equivalent queue system analysis, we prove that the proposed algorithm can achieve at least a constant fraction of the capacity region in the many-channel regime, and our numerical studies indicate that the proposed distributed collision-queue-regulated algorithm achieves a throughput very close to that achievable by a centralized throughput-optimal back-pressure-based scheduling algorithm.