Rate-Splitting Coordination for Emergency Unmanned Aerial Vehicle Network Coverage Optimization

Abstract

The rapid deployment of communication infrastructure is critical during natural disasters, where terrestrial networks are frequently compromised or entirely destroyed. Unmanned aerial vehicles have emerged as a highly flexible solution to provide on-demand emergency wireless coverage. However, managing co-channel interference and optimizing the trajectory of multiple unmanned aerial vehicles in a highly dynamic environment pose significant technical challenges. This paper investigates the application of rate-splitting multiple access as a coordination mechanism for emergency unmanned aerial vehicle networks. By splitting user messages into common and private parts, rate-splitting multiple access provides a generalized and robust interference management framework that bridges the gap between space-division multiple access and non-orthogonal multiple access. We formulate a joint optimization problem to maximize the minimum user rate, ensuring fairness and optimal coverage in disaster zones, by jointly optimizing the multi-unmanned aerial vehicle trajectories, power allocation, and rate-splitting parameters. Given the non-convex nature of the problem, we propose an alternating optimization algorithm based on successive convex approximation. Extensive simulations demonstrate that the proposed rate-splitting coordination approach significantly outperforms conventional orthogonal and non-orthogonal multiple access schemes in terms of coverage probability, energy efficiency, and overall network throughput. The results highlight the potential of rate-splitting to enhance the resilience and capacity of next-generation aerial emergency communication systems.