Sum of Age-of-Information Minimization in Aerial IRSs Assisted Wireless Networks
Wenwen Jiang, Bo Ai, Jing Cheng, Yichuan Lin, Guangyang Zhang · IEEE Communications Letters · 2023
In this letter, we investigate a blocked wireless network in which multiple aerial intelligent reconfigurable surfaces (IRSs) mounted on unmanned aerial vehicles (UAVs) are deployed to assist devices in communication with one base station (BS). To improve the freshness of information received at the BS, we formulate a sum of age-of-information (AoI) minimization problem by optimizing the device scheduling, IRS phase shift, and deployment positions of aerial IRSs. The formulated problem is mixed-integer non-convex due to the existence of binary variables and the coupling among variables. To solve it, we commence by applying the clustering algorithm to reduce the complexity of global scheduling. Then, we decouple the optimization variables and propose an iterative algorithm based on binary variable relaxation and successive convex approximation (SCA) approach to deal with the non-linear relations among variables. Simulation results demonstrate that the proposed algorithm outperforms the benchmarks in improving the information freshness.