Game Theoretical Approaches for Cooperative UAV NOMA Networks

Wireless communication systems assisted by unmanned aerial vehicles (UAVs) can well extend the coverage of conventional communication networks and quickly provide service wherein the communication infrastructures are destroyed. However, radio resources are always limited and coupled with complex interference in the orthogonal multiple access framework. Thus, non-orthogonal multiple access (NOMA), which can enhance spectrum efficiency and inherently has capability to mitigate interference, is integrated with UAV communication networks in this article. We first propose a cooperative UAV NOMA network (CUNN) architecture and analyze its technical challenges. In addition, with the goal of cooperatively or competitively utilizing the limited resources effectively in a distributed manner, game theory shows its potential in addressing various technical challenges in wireless networks. Thus, we further survey game theoretical approaches for NOMA networks and UAV-based relay networks, and provide insights on how these game theoretical approaches can be adopted to solve technical challenges in CUNNs. Finally, aiming to achieve high spectrum efficiency and ensure fairness among user equipments, we propose a UAV-iUE (isolated user equipment) association, UAVs' position optimization, and power allocation algorithm in a dynamic cooperative game-theoretic framework. In the numerical results and discussions Section, the effectiveness of the proposed dynamic cooperative game-theoretic framework is shown through multiple simulations.