论文标题
可重新配置智能表面辅助无人机通信的混合脱机线设计设计
Hybrid Offline-Online Design for Reconfigurable Intelligent Surface Aided UAV Communication
论文作者
论文摘要
这封信认为在里奇亚人褪色渠道下的城市地区可重构的智能表面（RIS）无人驾驶汽车（UAV）通信系统。提出了一种混合离线Online设计，以通过利用统计通道状态信息（S-CSI）和瞬时通道状态信息（I-CSI）来改善系统性能。对于离线阶段，我们旨在通过共同优化RIS的相移和无人机轨迹来最大化基于S-CSI的预期平均可实现率。由于其非凸度性，因此很难解决该配方的随机优化问题。为了解决这个问题，我们通过利用随机连续的凸近似（SSCA）技术提出了有效的算法。对于在线阶段，无人机根据有效的I-CSI适应性地调整了发射光束成形和用户调度。数值结果验证了所提出的混合设计的性能要比各种Bechmark方案都更好，并且还表现出系统性能和CSI开销之间的良好权衡。
This letter considers the reconfigurable intelligent surface (RIS)-aided unmanned aerial vehicle (UAV) communication systems in urban areas under the general Rician fading channel. A hybrid offline-online design is proposed to improve the system performance by leveraging both the statistical channel state information (S-CSI) and instantaneous channel state information (I-CSI). For the offline phase, we aim to maximize the expected average achievable rate based on the S-CSI by jointly optimizing the RIS's phase-shift and UAV trajectory. The formulated stochastic optimization problem is difficult to solve due to its non-convexity. To tackle this problem, we propose an efficient algorithm by leveraging the stochastic successive convex approximation (SSCA) techniques. For the online phase, the UAV adaptively adjusts the transmit beamforming and user scheduling according to the effective I-CSI. Numerical results verify that the proposed hybrid design performs better than various bechmark schemes, and also demonstrate a favorable trade-off between system performance and CSI overhead.
