When Split Federated Learning Meets Prototype Learning: A Communication-Efficient Approach in Wireless Networks

Federated Learning over 5G/6G Networks: Dynamic Client Selection and Resource Allocation for Heterogeneous Edge Environments

Federated learning (FL) has emerged as a promising paradigm for privacy-preserving edge intelligence because it enables geographically distributed devices to collaboratively train a shared model without transferring raw data to a central cloud. This capability is particularly valuable for 5G and emerging 6G networks, where edge-native services are required to satisfy stringent latency, bandwidth, and privacy constraints while operating on highly heterogeneous devices and time-varying wireless channels. In practice, however, synchronous FL is often constrained by straggling clients with limited computation capability or unfavorable communication conditions, which increases round latency and reduces overall resource efficiency. To address this challenge, this study develops a rigorously structured framework for dynamic client selection and radio resource allocation in heterogeneous wireless edge environments. Each FL round is formulated as a latency-aware scheduling problem that jointly captures local computation time, uplink transmission time, minimum participation constraints, and resource block assignment. On this basis, we propose a Dynamic Client Selection and Resource Allocation (DCS-RA) method that integrates computation-aware, channel-aware, and fairness-aware scoring with greedy resource block allocation guided by marginal completion time reduction. The study further provides a clear methodological structure, workflow visualization, literature-grounded justification, dataset documentation, and uncertainty-aware result reporting. Under the reported simulation setting with 100 clients and 20 resource blocks, DCS-RA reduces the average round completion time from 1.92 s to 1.55 s on MNIST and from 2.02 s to 1.57 s on CIFAR-10, corresponding to improvements of 19.39% and 22.47%, respectively. Standard deviation reductions of 70.59% and 80.77% further indicate improved round-to-round stability and more reliable training behavior. These results support the central conclusion that lightweight joint scheduling can materially improve wall-clock FL efficiency in heterogeneous 5G/6G edge networks.

DASFL: Dynamic Adaptive Split Federated Learning for Heterogeneous Clients

FSLT: A Federated Split Learning Testbed for 5G Wireless Networks

With the emergence of next-generation communication technologies, the integration of AI into next-generation wireless networks is becoming an important step toward achieving distributed intelligence. Different distributed learning frameworks, such as federated learning (FL) and split learning (SL), enable collaborative model training by distributing computation between user equipment (UEs) and edge servers. However, FL suffers from high communication overhead due to frequent model synchronization, while SL introduces significant latency at the split layer and is sensitive to channel conditions. The effects of wireless channel dynamics on distributed learning performance and the communication-computation trade-offs across different split layers remain insufficiently studied in practical scenarios. In this work, we present a Federated Split Learning Testbed (FSLT) over 5G wireless networks that integrates FL and SL within an OpenAirInterface (OAI) software-defined radio platform. FSLT enables empirical evaluation of learning–communication trade-offs under realistic wireless conditions. The framework distributes neural network layers between UEs and edge servers, allowing investigation of channel variability, latency, and split-point selection on training performance. Experiments on an avatar skeleton extraction task demonstrate that FSLT reduces communication load by 5%-8% compared with FL and achieves faster convergence than SL under dynamic channel conditions. These results provide practical insights into optimizing distributed learning over 5G edge systems and pave the way toward AI-native 6G networks.

Communication-Efficient Over-the-Air Federated Learning via Lightweight Gradient Compression

Integrating over-the-air computations into the model aggregation process of federated learning (FL) offers a promising solution to mitigate the communication bottleneck in FL model training. In this approach, all the clients modulate their intermediate parameters, such as gradients, onto the same set of orthogonal waveforms and transmit the resulting signals to the edge server simultaneously. Capitalizing on the superposition property of the radio channel, the server can extract an automatically aggregated global gradient from the received radio signal. However, the limited number of orthogonal waveforms imposes a constraint on the dimensionality of transmittable updates, hindering the adoption of more advanced, but high-dimensional models. In light of this challenge, we propose OFLight, a lightweight, yet effective, gradient compression algorithm tailored for OTA-FL systems. Specifically, in each communication round, the edge server constructs a low-rank projection matrix based on the received gradient matrix from the previous round (initialized with an independent and identically distributed standard normal matrix in the first round) and broadcasts it, along with the global model, to all clients in the system. Based on this matrix, every client projects its locally updated gradient matrix into a low-dimensional subspace through a linear operation. The clients upload only their compressed gradients via OTA computations, and the edge server can perform a linear decompression on the received signal, retrieving the original gradient dimension. Moreover, an error feedback mechanism is incorporated to compensate for the approximation error under aggressive compression. We derive analytical expressions for the convergence rate of both convex and non-convex loss functions, quantitatively demonstrating the effect of OFLight on the OTA-FL training efficiency. We also conduct extensive experiments to corroborate the efficacy of the proposed method.

Resilient Decentralized Wireless Federated Learning via Gradient Tracking with AdamW

Wireless Internet-of-Things (IoT) edge networks require decentralized learning (DecL) methods that can operate reliably under both heterogeneous local data and communication-constrained wireless links. However, existing decentralized optimization schemes often incur substantial communication overhead and degraded performance when transmissions are constrained by strict airtime budgets, fading channels, and packet losses. This paper proposes QEF-GT-AdamW, a communication-efficient and outage-resilient algorithm for DecL over wireless communication (WCom) networks. The proposed method combines gradient tracking to mitigate the effect of non-IID data, AdamW-based adaptive optimization to improve training stability, and dual-stream biased quantization with error feedback to reduce communication payloads for both model and tracking exchanges. To address unreliable broadcast communication, the proposed framework further employs a local fallback strategy when scheduled packets are not successfully received. We explicitly model the effect of bandwidth, transmit power, airtime constraints, and fading channels on DecL performance, and establish convergence guarantees for the proposed algorithm under compressed and unreliable wireless communication. Experimental results on heterogeneous MNIST and CIFAR-10 settings show that QEF-GT-AdamW consistently improves robustness and convergence performance over representative DecL baselines while achieving favorable accuracy-communication trade-offs under limited wireless resources.

Coalitional Game-Based Clustered Federated Learning for Mitigating Data Heterogeneity in Wireless Networks

Federated Learning (FL) has emerged as a promising paradigm for privacy-preserving distributed machine learning across mobile and edge devices. Nevertheless, the presence of non-independent and identically distributed (non-IID) data in wireless networks often leads to severe gradient divergence, slow convergence, and degraded model performance. To mitigate these challenges, this paper proposes FedCoalition, a coalition game-based clustered federated learning framework that organizes clients into collaborative coalitions according to the similarity of their model updates. The proposed method integrates a coalition formation mechanism with similarity-aware clustering to reduce gradient divergence among participating clients. In addition, each coalition designates a Coalition Head (CH) responsible for intra-cluster aggregation and model validation using auxiliary data, thereby improving model reliability and communication efficiency. The experimental results on MNIST and CIFAR-10 under non-IID data distributions demonstrate that FedCoalition significantly improves learning performance, achieving higher accuracy and faster convergence compared with existing clustered federated learning approaches.