作为图形数据的有效神经网络模型，图形神经网络（GNN）最近找到了针对各种无线优化问题的成功应用程序。鉴于GNN的推理阶段可以自然地以分散的方式实施，因此GNN是下一代无线通信中分散控制/管理的潜在推动力。但是，由于在与GNN的分散推断期间，邻居之间的信息交流可能会发生隐私泄漏。为了解决这个问题，在本文中，我们分析并增强了无线网络中GNN分散推断的隐私。具体来说，我们采用当地的差异隐私作为指标，设计了新颖的隐私信号以及隐私保证的培训算法，以实现保护隐私的推论。我们还定义了SNR私人关系权衡功能，以分析无线网络中使用GNN的分散推理的性能上限。为了进一步提高沟通和计算效率，我们采用了空中计算技术，理论上证明了其在隐私保护方面的优势。通过对合成图数据的大量模拟，我们验证了理论分析，验证提出的隐私无线信号传导和隐私保证培训算法的有效性，并就实际实施提供一些指导。

As an efficient graph analytical tool, graph neural networks (GNNs) have special properties that are particularly fit for the characteristics and requirements of wireless communications, exhibiting good potential for the advancement of next-generation wireless communications. This article aims to provide a comprehensive overview of the interplay between GNNs and wireless communications, including GNNs for wireless communications (GNN4Com) and wireless communications for GNNs (Com4GNN). In particular, we discuss GNN4Com based on how graphical models are constructed and introduce Com4GNN with corresponding incentives. We also highlight potential research directions to promote future research endeavors for GNNs in wireless communications.

图形神经网络（GNN）是图形数据的有效的神经网络模型，广泛用于不同的领域，包括无线通信。与其他神经网络模型不同，GNN可以以分散的方式实现，其中邻居之间的信息交换，使其成为无线通信系统中分散控制的潜在强大的工具。然而，主要的瓶颈是无线频道损伤，其恶化了GNN的预测稳健性。为了克服这个障碍，我们在本文中分析和增强了不同无线通信系统中分散的GNN的鲁棒性。具体地，使用GNN二进制分类器作为示例，我们首先开发一种方法来验证预测是否稳健。然后，我们在未编码和编码的无线通信系统中分析分散的GNN二进制分类器的性能。为了解决不完美的无线传输并增强预测稳健性，我们进一步提出了用于上述两个通信系统的新型重传机制。通过仿真对合成图数据，我们验证了我们的分析，验证了提出的重传机制的有效性，并为实际实施提供了一些见解。

Deep learning-based approaches have been developed to solve challenging problems in wireless communications, leading to promising results. Early attempts adopted neural network architectures inherited from applications such as computer vision. They often yield poor performance in large scale networks (i.e., poor scalability) and unseen network settings (i.e., poor generalization). To resolve these issues, graph neural networks (GNNs) have been recently adopted, as they can effectively exploit the domain knowledge, i.e., the graph topology in wireless communications problems. GNN-based methods can achieve near-optimal performance in large-scale networks and generalize well under different system settings, but the theoretical underpinnings and design guidelines remain elusive, which may hinder their practical implementations. This paper endeavors to fill both the theoretical and practical gaps. For theoretical guarantees, we prove that GNNs achieve near-optimal performance in wireless networks with much fewer training samples than traditional neural architectures. Specifically, to solve an optimization problem on an $n$-node graph (where the nodes may represent users, base stations, or antennas), GNNs' generalization error and required number of training samples are $\mathcal{O}(n)$ and $\mathcal{O}(n^2)$ times lower than the unstructured multi-layer perceptrons. For design guidelines, we propose a unified framework that is applicable to general design problems in wireless networks, which includes graph modeling, neural architecture design, and theory-guided performance enhancement. Extensive simulations, which cover a variety of important problems and network settings, verify our theory and the effectiveness of the proposed design framework.

随着数据生成越来越多地在没有连接连接的设备上进行，因此与机器学习（ML）相关的流量将在无线网络中无处不在。许多研究表明，传统的无线协议高效或不可持续以支持ML，这创造了对新的无线通信方法的需求。在这项调查中，我们对最先进的无线方法进行了详尽的审查，这些方法是专门设计用于支持分布式数据集的ML服务的。当前，文献中有两个明确的主题，模拟的无线计算和针对ML优化的数字无线电资源管理。这项调查对这些方法进行了全面的介绍，回顾了最重要的作品，突出了开放问题并讨论了应用程序方案。

联合学习（FL）最近被揭示为有希望的技术，以便在网络边缘启用人工智能（AI），其中分布式移动设备在边缘服务器的协调下协同培训共享AI模型。为了显着提高FL的通信效率，通过利用无线多接入信道的叠加特性，遍布空中计算允许大量的移动设备通过利用无线多接入信道的叠加特性同时上传其本地模型。由于无线信道衰落，边缘服务器的模型聚合误差由所有设备中最弱的通道主导，导致严重的孤立问题。在本文中，我们提出了一种继电器协助的合作液计划，以有效地解决了斯塔格勒问题。特别是，我们部署了多个半双工继电器以协同协作在将本地模型更新上载到边缘服务器时的设备。空中计算的性质构成了与传统继电器通信系统中不同的系统目标和约束。此外，设计变量之间的强耦合使得这种系统具有挑战性的优化。为了解决问题，我们提出了一种基于交替优化的算法来优化收发器和中继操作，具有低复杂度。然后，我们在单个中继盒中分析模型聚合误差，并显示我们的继电器辅助方案实现比没有继电器的中继的误差较小的误差。该分析提供了对协同媒体实施中的继电器部署的关键见解。广泛的数值结果表明，与最先进的方案相比，我们的设计达到了更快的融合。

Communication and computation are often viewed as separate tasks. This approach is very effective from the perspective of engineering as isolated optimizations can be performed. On the other hand, there are many cases where the main interest is a function of the local information at the devices instead of the local information itself. For such scenarios, information theoretical results show that harnessing the interference in a multiple-access channel for computation, i.e., over-the-air computation (OAC), can provide a significantly higher achievable computation rate than the one with the separation of communication and computation tasks. Besides, the gap between OAC and separation in terms of computation rate increases with more participating nodes. Given this motivation, in this study, we provide a comprehensive survey on practical OAC methods. After outlining fundamentals related to OAC, we discuss the available OAC schemes with their pros and cons. We then provide an overview of the enabling mechanisms and relevant metrics to achieve reliable computation in the wireless channel. Finally, we summarize the potential applications of OAC and point out some future directions.

由于处理非covex公式的能力，深入研究深度学习（DL）技术以优化多用户多输入单输出（MU-MISO）下行链接系统。但是，现有的深神经网络（DNN）的固定计算结构在系统大小（即天线或用户的数量）方面缺乏灵活性。本文开发了一个双方图神经网络（BGNN）框架，这是一种可扩展的DL溶液，旨在多端纳纳波束形成优化。首先，MU-MISO系统以两分图为特征，其中两个不相交的顶点集（由传输天线和用户组成）通过成对边缘连接。这些顶点互连状态是通过通道褪色系数建模的。因此，将通用的光束优化过程解释为重量双分图上的计算任务。这种方法将波束成型的优化过程分为多个用于单个天线顶点和用户顶点的子操作。分离的顶点操作导致可扩展的光束成型计算，这些计算不变到系统大小。顶点操作是由一组DNN模块实现的，这些DNN模块共同构成了BGNN体系结构。在所有天线和用户中都重复使用相同的DNN，以使所得的学习结构变得灵活地适合网络大小。 BGNN的组件DNN在许多具有随机变化的网络尺寸的MU-MISO配置上进行了训练。结果，训练有素的BGNN可以普遍应用于任意的MU-MISO系统。数值结果验证了BGNN框架比常规方法的优势。

在这项工作中，我们考虑了具有多个基站和间隔干扰的无线系统中的联合学习模型。在学习阶段，我们应用了一个不同的私人方案，将信息从用户传输到其相应的基站。我们通过在其最佳差距上得出上限来显示学习过程的收敛行为。此外，我们定义了一个优化问题，以减少该上限和总隐私泄漏。为了找到此问题的本地最佳解决方案，我们首先提出了一种计划资源块和用户的算法。然后，我们扩展了该方案，以通过优化差异隐私人工噪声来减少总隐私泄漏。我们将这两个程序的解决方案应用于联合学习系统的参数。在这种情况下，我们假设每个用户都配备了分类器。此外，假定通信单元的资源块比用户数量少。仿真结果表明，与随机调度程序相比，我们提出的调度程序提高了预测的平均准确性。此外，其具有噪声优化器的扩展版本大大减少了隐私泄漏的量。

In split machine learning (ML), different partitions of a neural network (NN) are executed by different computing nodes, requiring a large amount of communication cost. To ease communication burden, over-the-air computation (OAC) can efficiently implement all or part of the computation at the same time of communication. Based on the proposed system, the system implementation over wireless network is introduced and we provide the problem formulation. In particular, we show that the inter-layer connection in a NN of any size can be mathematically decomposed into a set of linear precoding and combining transformations over MIMO channels. Therefore, the precoding matrix at the transmitter and the combining matrix at the receiver of each MIMO link, as well as the channel matrix itself, can jointly serve as a fully connected layer of the NN. The generalization of the proposed scheme to the conventional NNs is also introduced. Finally, we extend the proposed scheme to the widely used convolutional neural networks and demonstrate its effectiveness under both the static and quasi-static memory channel conditions with comprehensive simulations. In such a split ML system, the precoding and combining matrices are regarded as trainable parameters, while MIMO channel matrix is regarded as unknown (implicit) parameters.

In recent years, mobile devices are equipped with increasingly advanced sensing and computing capabilities. Coupled with advancements in Deep Learning (DL), this opens up countless possibilities for meaningful applications, e.g., for medical purposes and in vehicular networks. Traditional cloudbased Machine Learning (ML) approaches require the data to be centralized in a cloud server or data center. However, this results in critical issues related to unacceptable latency and communication inefficiency. To this end, Mobile Edge Computing (MEC) has been proposed to bring intelligence closer to the edge, where data is produced. However, conventional enabling technologies for ML at mobile edge networks still require personal data to be shared with external parties, e.g., edge servers. Recently, in light of increasingly stringent data privacy legislations and growing privacy concerns, the concept of Federated Learning (FL) has been introduced. In FL, end devices use their local data to train an ML model required by the server. The end devices then send the model updates rather than raw data to the server for aggregation. FL can serve as an enabling technology in mobile edge networks since it enables the collaborative training of an ML model and also enables DL for mobile edge network optimization. However, in a large-scale and complex mobile edge network, heterogeneous devices with varying constraints are involved. This raises challenges of communication costs, resource allocation, and privacy and security in the implementation of FL at scale. In this survey, we begin with an introduction to the background and fundamentals of FL. Then, we highlight the aforementioned challenges of FL implementation and review existing solutions. Furthermore, we present the applications of FL for mobile edge network optimization. Finally, we discuss the important challenges and future research directions in FL.

联合学习（FL）使移动设备能够在保留本地数据的同时协作学习共享的预测模型。但是，实际上在移动设备上部署FL存在两个主要的研究挑战：（i）频繁的无线梯度更新v.s.频谱资源有限，以及（ii）培训期间渴望的FL通信和本地计算V.S.电池约束的移动设备。为了应对这些挑战，在本文中，我们提出了一种新型的多位空天空计算（MAIRCOMP）方法，用于FL中本地模型更新的频谱有效聚合，并进一步介绍用于移动的能源有效的FL设计设备。具体而言，高精度数字调制方案是在MAIRCOMP中设计和合并的，允许移动设备同时在多访问通道中同时在所选位置上传模型更新。此外，我们理论上分析了FL算法的收敛性。在FL收敛分析的指导下，我们制定了联合传输概率和局部计算控制优化，旨在最大程度地减少FL移动设备的总体能源消耗（即迭代局部计算 +多轮通信）。广泛的仿真结果表明，我们提出的方案在频谱利用率，能源效率和学习准确性方面优于现有计划。

本文通过匹配的追求方法开发了一类低复杂设备调度算法，以实现空中联合学习。提出的方案紧密跟踪了通过差异编程实现的接近最佳性能，并且基于凸松弛的众所周知的基准算法极大地超越了众所周知的基准算法。与最先进的方案相比，所提出的方案在系统上构成了较低的计算负载：对于$ k $设备和参数服务器上的$ n $ antennas，基准的复杂性用$ \ left缩放（n^）2 + k \ right）^3 + n^6 $，而提出的方案量表的复杂性则以$ 0 <p，q \ leq 2 $为$ k^p n^q $。通过CIFAR-10数据集上的数值实验证实了所提出的方案的效率。

在本文中，我们旨在改善干扰限制的无线网络中超级可靠性和低延迟通信（URLLC）的服务质量（QoS）。为了在通道连贯性时间内获得时间多样性，我们首先提出了一个随机重复方案，该方案随机将干扰能力随机。然后，我们优化了每个数据包的保留插槽数量和重复数量，以最大程度地减少QoS违规概率，该概率定义为无法实现URLLC的用户百分比。我们构建了一个级联的随机边缘图神经网络（REGNN），以表示重复方案并开发一种无模型的无监督学习方法来训练它。我们在对称场景中使用随机几何形状分析了QoS违规概率，并应用基于模型的详尽搜索（ES）方法来找到最佳解决方案。仿真结果表明，在对称方案中，通过模型学习方法和基于模型的ES方法实现的QoS违规概率几乎相同。在更一般的情况下，级联的Regnn在具有不同尺度，网络拓扑，细胞密度和频率重复使用因子的无线网络中很好地概括了。在模型不匹配的情况下，它的表现优于基于模型的ES方法。

Over-the-air computation has the potential to increase the communication-efficiency of data-dependent distributed wireless systems, but is vulnerable to eavesdropping. We consider over-the-air computation over block-fading additive white Gaussian noise channels in the presence of a passive eavesdropper. The goal is to design a secure over-the-air computation scheme. We propose a scheme that achieves MSE-security against the eavesdropper by employing zero-forced artificial noise, while keeping the distortion at the legitimate receiver small. In contrast to former approaches, the security does not depend on external helper nodes to jam the eavesdropper's receive signal. We thoroughly design the system parameters of the scheme, propose an artificial noise design that harnesses unused transmit power for security, and give an explicit construction rule. Our design approach is applicable both if the eavesdropper's channel coefficients are known and if they are unknown in the signal design. Simulations demonstrate the performance, and show that our noise design outperforms other methods.

通过增加无线设备的计算能力，以及用户和设备生成的数据的前所未有的级别，已经出现了新的分布式机器学习（ML）方法。在无线社区中，由于其通信效率及其处理非IID数据问题的能力，联邦学习（FL）特别有趣。可以通过称为空中计算（AIRCOMP）的无线通信方法加速FL训练，其利用同时上行链路传输的干扰以有效地聚合模型更新。但是，由于Aircomp利用模拟通信，因此它引入了不可避免的估计错误。在本文中，我们研究了这种估计误差对FL的收敛性的影响，并提出了一种改进资源受限无线网络的方法的转移。首先，我们通过静态通道重新传输获得最佳Aircomp电源控制方案。然后，我们调查了传递的空中流体的性能，并在流失函数上找到两个上限。最后，我们提出了一种选择最佳重传的启发式，可以在训练ML模型之前计算。数值结果表明，引入重传可能导致ML性能提高，而不会在通信或计算方面产生额外的成本。此外，我们为我们的启发式提供了模拟结果，表明它可以正确地确定不同无线网络设置和机器学习问题的最佳重传次数。

在本文中，我们研究了具有差异隐私（DP）的学习图神经网络（GNN）的问题。我们提出了一种基于聚合扰动（GAP）的新型差异私有GNN，该GNN为GNN的聚合函数添加了随机噪声，以使单个边缘（边缘级隐私）或单个节点的存在统计上的存在及其所有邻接边缘（ - 级别的隐私）。 GAP的新体系结构是根据私人学习的细节量身定制的，由三个单独的模块组成：（i）编码器模块，我们在不依赖边缘信息的情况下学习私人节点嵌入； （ii）聚合模块，其中我们根据图结构计算嘈杂的聚合节点嵌入； （iii）分类模块，我们在私有聚合上训练神经网络进行节点分类，而无需进一步查询图表。 GAP比以前的方法的主要优势在于，它可以从多跳社区的聚合中受益，并保证边缘级别和节点级别的DP不仅用于培训，而且可以推断出培训的隐私预算以外的额外费用。我们使用R \'Enyi DP来分析GAP的正式隐私保证，并在三个真实世界图数据集上进行经验实验。我们证明，与最先进的DP-GNN方法和天真的MLP基线相比，GAP提供了明显更好的准确性私人权衡权衡。

Federated Edge Learning（Feel）已成为一种革命性的范式，可以在6G无线网络的边缘开发AI服务，因为它支持大量移动设备的协作模型培训。但是，无线通道上的模型通信，尤其是在上行链路模型上传的感觉中，已被广泛认为是一种严重限制感觉效率的瓶颈。尽管无线计算可以减轻广播资源在感觉上传中的过度成本，但无线空中感觉的实际实施仍然遭受了一些挑战，包括强烈的Straggler问题，大型沟通开销和潜在的隐私泄漏。在本文中，我们研究了这些挑战，并利用了未来无线系统的关键推动力，以应对这些挑战。我们研究了有关RIS授权的感觉的最新解决方案，并探索采用RIS增强感觉性能的有希望的研究机会。

联合学习（FL）能够通过定期聚合培训的本地参数来在多个边缘用户执行大的分布式机器学习任务。为了解决在无线迷雾云系统上实现支持的关键挑战（例如，非IID数据，用户异质性），我们首先基于联合平均（称为FedFog）的高效流行算法来执行梯度参数的本地聚合在云端的FOG服务器和全球培训更新。接下来，我们通过调查新的网络知识的流动系统，在无线雾云系统中雇用FEDFog，这促使了全局损失和完成时间之间的平衡。然后开发了一种迭代算法以获得系统性能的精确测量，这有助于设计有效的停止标准以输出适当数量的全局轮次。为了缓解级体效果，我们提出了一种灵活的用户聚合策略，可以先培训快速用户在允许慢速用户加入全局培训更新之前获得一定程度的准确性。提供了使用若干现实世界流行任务的广泛数值结果来验证FEDFOG的理论融合。我们还表明，拟议的FL和通信的共同设计对于在实现学习模型的可比准确性的同时，基本上提高资源利用是必要的。

Federated learning (FL) has achieved great success as a privacy-preserving distributed training paradigm, where many edge devices collaboratively train a machine learning model by sharing the model updates instead of the raw data with a server. However, the heterogeneous computational and communication resources of edge devices give rise to stragglers that significantly decelerate the training process. To mitigate this issue, we propose a novel FL framework named stochastic coded federated learning (SCFL) that leverages coded computing techniques. In SCFL, before the training process starts, each edge device uploads a privacy-preserving coded dataset to the server, which is generated by adding Gaussian noise to the projected local dataset. During training, the server computes gradients on the global coded dataset to compensate for the missing model updates of the straggling devices. We design a gradient aggregation scheme to ensure that the aggregated model update is an unbiased estimate of the desired global update. Moreover, this aggregation scheme enables periodical model averaging to improve the training efficiency. We characterize the tradeoff between the convergence performance and privacy guarantee of SCFL. In particular, a more noisy coded dataset provides stronger privacy protection for edge devices but results in learning performance degradation. We further develop a contract-based incentive mechanism to coordinate such a conflict. The simulation results show that SCFL learns a better model within the given time and achieves a better privacy-performance tradeoff than the baseline methods. In addition, the proposed incentive mechanism grants better training performance than the conventional Stackelberg game approach.