Multi-UAV-Enabled Cognitive Radio Networks: Joint UAV Deployment and Resource Allocation Design

Abstract

Unmanned aerial vehicle (UAV)-aided communications may suffer from the coexistence with existing network infrastructure and the spectrum scarcity. Underlay cognitive radio technology should be employed to manage the secondary UAV-aided networks with the existing primary networks using the same frequency spectrum, where the interference to the primary network should be bounded. In this paper, we focus on the problem of multi-UAV-assisted underlay cognitive radio for multiple secondary users (SUs) and primary users (PUs). We establish an optimization problem to maximize the minimum throughput among SUs with respect to multi-UAV deployment locations, power and service ratio allocation. The problem is highly intractable due to its mixed-integer and non-convex nature. The problem is solved by decomposing it into two nested optimization problems. The inner problem involves joint power and service ratio allocation given the deployment location and UAV-SU allocation, which we transform equivalently into a convex optimization problem. The outer problem determines the multi-UAV deployment locations and UAV-SU allocation, solved via a metaheuristic method. Via this decomposition with the inner problem optimally solvable in polynomial time by a convex optimization solver, the search space of the metaheuristic algorithm is drastically reduced, resulting in an efficient nearoptimal algorithm for the complex problem. Numerical results demonstrate that the proposed approach achieves significant throughput improvement compared to baseline methods.

Authors 5

1. Paul Zheng Aachen Chair of Information Theory and Data Analytics

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University,Chair of Information Theory and Data Analytics,Germany

2. Boyao Li Aachen Chair of Information Theory and Data Analytics

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University,Chair of Information Theory and Data Analytics,Germany

3. Xiaopeng Yuan Aachen Chair of Information Theory and Data Analytics

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University,Chair of Information Theory and Data Analytics,Germany

4. Yulin Hu

   Wuhan University

   Affiliation as printed

   School of Electronic Information, Wuhan University,China

5. Anke Schmeink Aachen Chair of Information Theory and Data Analytics

   RWTH Aachen University

   Affiliation as printed

   RWTH Aachen University,Chair of Information Theory and Data Analytics,Germany