Peak Age of Information Minimization in UAV-assisted Cognitive Relay Networks

Age of information (AoI) is a new performance index proposed recently, which is used to describe the freshness of information. This paper studies
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oI minimization for the unmanned aerial vehicle (UAV)-assisted cognitive radio networks (CRN), where the primary users and secondary users share the authorized spectrum, and UAV as a relay adopts time division duplex (TDD) scheme for uplink and downlink transmissions. We focus on AoI minimization by jointly optimizing the UAV flight trajectory and resource allocation. Since the optimization problem is non-convex, we use an efficient successive convex approximation iterative algorithm to solve the optimal solution, while satisfying the conditions of interference threshold and feasibility constraints. Simulation results show that the proposed joint design scheme can effectively improve the freshness of information.