Distributed Joint Subchannel and Power Allocation for UAV Swarms with Blockchain Consensus

To alleviate the scarcity of available licensed spectrum resources for unmanned aerial vehicles (UAVs) and coordinate the mutual interference, efficient spectrum management is in urgent demand. This paper introduces a blockchain-enabled spectrum management framework for UAV swarms, where operators can share available resources in spectrum pool and UAVs can request frequencies on demand. Specifically, we formulate a joint subchannel allocation and power control problem to maximize the total capacity of UAV swarms. The formulated problem is NP-hard, and common global solution requires very high computational complexity. To reduce complexity, we propose a distributed scheme based on consensus mechanism, where each base station on the chain solves a sub-problem independently, and uses consensus mechanism to reach global consistency. To further control the interference among the sub-problems, we introduce an interference temperature on each channel to be used. Simulation results validate that our proposed scheme can improve the spectrum utilization with reduced complexity, as compared with conventional global solutions.