Joint throughput maximization, interference cancellation, and power efficiency for multi-IRS-empowered UAV communications

Contemporary mobile communication systems encounter formidable challenges in urban environments and dead zones, manifesting as issues in reliability, coverage, and quality of service (QoS). Addressing these challenges, the integration of intelligent reflecting surface (IRS)-assisted unmanned aerial vehicle (UAV) communications emerges as a transformative solution. This paradigm not only offloads ground base stations but also ensures reliability and QoS adherence in a cost-effective manner. Additionally, the synergistic deployment of reconfigurable intelligent surfaces (RIS) with non-orthogonal multiple access (NOMA) holds significant promise for elevating the performance of mobile networks. This paper delves into the integration of multi-IRS configurations to augment UAV communication within intelligent mobile networks. The overarching objective is to minimize average total power consumption while simultaneously maximizing network-wide throughput and reliability. This is achieved through the joint optimization of resource allocation, UAV trajectory, velocity, and IRS phase shift design. The focal point is to establish reliable and efficient connectivity for mobile users and Internet of Things (IoT) nodes across diverse scenarios, thereby ensuring QoS benchmarks and unlocking new commercial opportunities. Given the non-convex and NP-hard nature of the optimization problem, we first introduce a deep deterministic policy gradient algorithm to optimize multi-IRS multi-user associations, paving the way for efficient convergence. Subsequently, a sequential convex approximation (SCA) algorithm and a Dinkelbach-based approach are employed to optimize UAV trajectory, followed by the fine-tuning of successive interference cancellation (SIC) decoding order scheduling and power allocation. Theoretical analysis and performance evaluations substantiate the profound advantages of the proposed algorithm, showcasing commendable convergence rates and enhanced energy efficiency.