Interference Graph Based Spectrum Allocation for Blockchain-enabled CBRS System

As a pioneering trial for dynamic spectrum sharing, citizens broadband radio access (CBRS) encounters difficulties in effectively managing interference and spectrum allocation among general authorized access (GAA) users. In this paper, we propose a blockchain-enabled spectrum sharing model designed to ensure interference protection for high-priority users, while simultaneously enhance the quality of service (QoS) for GAA users. Specifically, we present a spectrum allocation scheme by constructing an interference graph among GAA users and propose an improved graph coloring algorithm to solve the spectrum allocation problem. This algorithm ensures the maximization of the number of users with channel licenses by prioritizing the allocation of channels to GAA users with smaller node degrees. Simulation results show that our proposed algorithm increases the number of unauthorized users that can be accommodated in the same scenario compared with the traditional greedy algorithm, which increases the spectrum utilization.