Transmission-Efficient RIS-Carrying UAV’s Auxiliary Communication Systems for Intelligent Connected Vehicle Platoons at the Unsignalized Intersection in Smart Cities

Abstract

Numerous interaction demands for smart cities have arisen due to the explosive growth of the Internet of Things and mobile communication. Due to its passive low energy consumption and affordable deployment cost, reconfigurable intelligent surface (RIS) is a potential key technology to develop a novel paradigm of wireless communication at unsignalized intersections. This paper studies the signal interaction between multiple vehicle platoons in different paths before entering an unsignalized intersection supported by UAV, which is usually difficult to solve without the assistance of communication. Under the limitation of calculation and transmission resources, the objective is to optimize the system’s transmission efficiency. The joint resource scheduling model of communication time and transmission power includes the coupling effects of vehicle dynamics, onboard computing, signal transmission and reflection, and energy consumption. A method based on the quasi-Newton and sequential quadratic programming (SQP) algorithm is designed to carry out optimization iteration. Finally, the simulation results show that this method is generally efficient and outperforms the benchmark methods.