While low-altitude wireless networks (LAWNs) based on uncrewed aerial vehicles (UAVs) offer high mobility, flexibility, and coverage for urban communications, they face severe signal attenuation in dense environments due to obstructions. To address this critical issue, we consider introducing collaborative beamforming (CB) of UAVs and omnidirectional reconfigurable beamforming (ORB) of simultaneous transmitting and reflecting reconfigurable intelligent surfaces (STAR-RIS) to enhance the signal quality and directionality. On this basis, we formulate a joint rate and energy optimization problem (JREOP) to maximize the transmission rate of the overall system, while minimizing the energy consumption of the UAV swarm. Due to the non-convex and NP-hard nature of JREOP, we propose a heterogeneous multi-agent collaborative dynamic (HMCD) optimization framework, which has two core components. The first component is a simulated annealing (SA)-based STAR-RIS control method, which dynamically optimizes reflection and transmission coefficients to enhance signal propagation. The second component is an improved multi-agent deep reinforcement learning (MADRL) control method, which incorporates a self-attention evaluation mechanism to capture interactions between UAVs and an adaptive velocity transition mechanism to enhance training stability. Simulation results demonstrate that HMCD outperforms various baselines in terms of convergence speed, average transmission rate, and energy consumption. Further analysis reveals that the average transmission rate of the overall system scales positively with both UAV count and STAR-RIS element numbers.

翻译：尽管基于无人机的低空无线网络为城市通信提供了高移动性、灵活性和覆盖能力，但在密集环境中因障碍物遮挡面临严重的信号衰减。为解决这一关键问题，本文考虑引入无人机的协同波束成形与同时透射反射可重构智能表面的全向可重构波束成形，以增强信号质量与方向性。在此基础上，我们构建了联合速率与能量优化问题，旨在最大化系统整体传输速率，同时最小化无人机集群的能耗。鉴于该问题的非凸性与NP难特性，我们提出了一种异构多智能体协同动态优化框架，其包含两个核心组件：第一是基于模拟退火的可重构智能表面控制方法，动态优化反射与透射系数以增强信号传播；第二是改进的多智能体深度强化学习控制方法，融合自注意力评估机制以捕捉无人机间交互，并采用自适应速度转换机制以提升训练稳定性。仿真结果表明，该框架在收敛速度、平均传输速率及能耗方面均优于多种基线方法。进一步分析揭示，系统整体平均传输速率随无人机数量与可重构智能表面单元数增加而呈正向增长。