论文标题
盲目的边缘学习
Blind Federated Edge Learning
论文作者
论文摘要
我们研究联合边缘学习(Feel),其中无线边缘设备都有自己的数据集,可以在无线访问点作为参数服务器(PS)的帮助下协作学习全局模型。在每次迭代中,无线设备使用其本地数据和从PS收到的最新全局模型执行本地更新,并通过无线淡出的多个访问频道(MAC)将其本地更新发送给PS。然后,PS根据通过无线MAC收到的信号更新全局模型,并与设备共享。由无线MAC的附加性质激励,我们提出了一个模拟“空中”聚合方案,其中设备以未编码的方式传输其本地更新。与最近有关空地学习的文献不同,在这里我们假设设备没有通道状态信息(CSI),而PS的CSI不完美。取而代之的是,PS具有多个天线以减轻该通道的破坏性效果,由于缺乏完美的CSI而加剧了该通道的破坏性效果。我们在PS上设计一个接收波束形成方案,并表明当PS具有足够数量的天线时,它可以补偿缺乏完美的CSI。我们还得出了所提出的算法的收敛速率,该算法突出了缺乏完美CSI的影响以及PS天线的数量。实验结果和收敛分析都说明了所提出的算法的性能提高了PS天线的数量,尽管PS具有足够数量的天线,但无线褪色MAC还是确定性的。
We study federated edge learning (FEEL), where wireless edge devices, each with its own dataset, learn a global model collaboratively with the help of a wireless access point acting as the parameter server (PS). At each iteration, wireless devices perform local updates using their local data and the most recent global model received from the PS, and send their local updates to the PS over a wireless fading multiple access channel (MAC). The PS then updates the global model according to the signal received over the wireless MAC, and shares it with the devices. Motivated by the additive nature of the wireless MAC, we propose an analog `over-the-air' aggregation scheme, in which the devices transmit their local updates in an uncoded fashion. Unlike recent literature on over-the-air edge learning, here we assume that the devices do not have channel state information (CSI), while the PS has imperfect CSI. Instead, the PS is equipped multiple antennas to alleviate the destructive effect of the channel, exacerbated due to the lack of perfect CSI. We design a receive beamforming scheme at the PS, and show that it can compensate for the lack of perfect CSI when the PS has a sufficient number of antennas. We also derive the convergence rate of the proposed algorithm highlighting the impact of the lack of perfect CSI, as well as the number of PS antennas. Both the experimental results and the convergence analysis illustrate the performance improvement of the proposed algorithm with the number of PS antennas, where the wireless fading MAC becomes deterministic despite the lack of perfect CSI when the PS has a sufficiently large number of antennas.