Joint Optimization of Trajectory and Discrete Reflection Coefficients for UAV-Aided Backscatter Communication System with NOMA

Backscatter communication is a promising technology for the Internet of Things (IoT) systems with low-energy consumption, in which data transmission backscatter devices relies on reflecting incident signal. However, limited by low power characteristic reflected signal from devices, achieving efficient collection widely distributed thorny problem. Considering that unmanned aerial vehicles (UAVs) have flexible deployment capability, employing UAVs network can achieve feasible devices. In this paper, we consider UAV-aided system and introduce Non-orthogonal multiple access (NOMA) to enable UAV collect signals simultaneously. We formulate an optimization problem maximize throughput considered jointly designing device matching, trajectory UAV, reflection coefficients non-convex challenging solve. Hence, decouple original into three sub-problems propose iterative algorithm based Block Coordinate Descent (BCD) solve them. detail, game-based matching designed ensure needs remote The are optimized through Successive Convex Approximation (SCA) relaxation algorithm. By sub-problems, solved. simulation results show proposed scheme obtain significant gain compared benchmark schemes.