论文标题
通过无线计算加速分布式优化
Accelerating Distributed Optimization via Over-the-Air Computing
论文作者
论文摘要
分布式优化在新兴应用程序中无处不在,例如强大的传感器网络控制,智能电网管理,机器学习,资源切片和本地化。但是,本地和中央节点之间的广泛数据交换可能会导致严重的通信瓶颈。为了克服这一挑战,无线计算(AIRCOMP)是一种有希望的中型访问技术,它利用无线多访问通道(MAC)的叠加属性并提供了可观的带宽节省。在这项工作中,我们为一般分布式凸优化问题提出了一个AIRCOMP框架。具体而言,使用分布式pripallual(DPD)亚级别方法用于优化过程。在一般假设下,我们证明dpdaircomp可以渐近地实现零预期的约束违规。因此,尽管存在通道褪色和附加噪声,但DPD-AirComp仍确保原始问题的可行性。此外,通过对用户信号进行适当的功率控制,也可以减轻预期的非零最优差距。提出了提出的框架的两个实际应用,即智能电网管理和无线资源分配。最后,数值结果重新确认了DPDAIRCOM的出色性能,而与数字正交多重访问方案相比,DPD-AIRCOMP的收敛速度更快,特别是时间划分多重访问(TDMA)。
Distributed optimization is ubiquitous in emerging applications, such as robust sensor network control, smart grid management, machine learning, resource slicing, and localization. However, the extensive data exchange among local and central nodes may cause a severe communication bottleneck. To overcome this challenge, over-the-air computing (AirComp) is a promising medium access technology, which exploits the superposition property of the wireless multiple access channel (MAC) and offers significant bandwidth savings. In this work, we propose an AirComp framework for general distributed convex optimization problems. Specifically, a distributed primaldual (DPD) subgradient method is utilized for the optimization procedure. Under general assumptions, we prove that DPDAirComp can asymptotically achieve zero expected constraint violation. Therefore, DPD-AirComp ensures the feasibility of the original problem, despite the presence of channel fading and additive noise. Moreover, with proper power control of the users' signals, the expected non-zero optimality gap can also be mitigated. Two practical applications of the proposed framework are presented, namely, smart grid management and wireless resource allocation. Finally, numerical results reconfirm DPDAirComp's excellent performance, while it is also shown that DPD-AirComp converges an order of magnitude faster compared to a digital orthogonal multiple access scheme, specifically, time division multiple access (TDMA).