A Joint Learning and Communications Framework for Federated Learning Over Wireless Networks
Mingzhe ChenZhaohui YangW. SaadChangchuan YinH. PoorShuguang Cui
Develops an analytical framework for wireless federated learning that derives the mathematical impact of channel packet errors on convergence and jointly optimizes user selection, transmit power, and resource allocation to minimize model loss.
Federated learning enables mobile devices to collaboratively train artificial intelligence models using local data, protecting user privacy and avoiding the massive bandwidth costs of centralizing raw datasets. However, deploying federated learning over commercial wireless cellular networks introduces operational challenges. Wireless channels suffer from interference, packet transmission errors, latency, and limited spectrum and battery energy. When device updates are corrupted or dropped, the accuracy and convergence speed of the shared machine learning model degrade significantly. Addressing these communication bottlenecks is essential for making decentralized intelligence practical on mobile and edge devices.
The main objective of the article is to establish and evaluate a joint learning and communication framework that minimizes machine learning training loss over wireless networks by systematically optimizing user selection, wireless resource allocation, and device transmit power.
To achieve this, the article analyzes a cellular uplink network where distributed devices transmit local model updates to a central base station using orthogonal frequency division multiple access. The authors derive a closed-form mathematical expression for the expected convergence rate of the federated learning algorithm under packet transmission errors. Using this theoretical convergence bound, they simplify the training loss minimization problem into a bipartite matching formulation that strictly enforces per-round transmission delay and device energy limits. The base station determines optimal device transmit powers analytically and allocates wireless resource blocks using the standard Hungarian matching algorithm. The framework is validated through numeric simulations using synthetic linear regression tasks and image classification on the MNIST handwritten digit dataset across varying user counts and bandwidth allocations.
The findings show that wireless impairments create a quantifiable performance gap between practical federated learning and idealized error-free training, but this gap can be minimized through joint network and learning optimization. In image identification tests, the proposed joint framework improves model accuracy by up to 1.4% compared to optimal user selection with random resource allocation, by 3.5% compared to standard wireless federated learning with random user selection, and by 4.1% compared to conventional wireless resource management that minimizes packet errors without considering machine learning parameters. The theoretical convergence rate closely aligns with simulation results, exhibiting less than a 9% discrepancy. Furthermore, the analysis demonstrates that while increasing user participation supplies more data to improve model quality, performance gains plateau once the base station receives sufficient data samples (e.g., beyond approximately 30 samples per user in linear regression), meaning network managers do not need to schedule every device in every round.
These results indicate that treating wireless network management and machine learning design as separate domains leads to suboptimal artificial intelligence performance. Cellular operators and edge computing architects can implement learning-aware scheduling at the base station to achieve higher prediction accuracy and faster model convergence without requiring additional hardware or spectral bandwidth. By accounting for device sample counts, channel reliability, and local energy constraints simultaneously, network operators reduce operational risks such as training stalls, battery drain, and excessive latency in time-sensitive edge applications.
Organizations deploying federated learning over wireless infrastructure should integrate joint user selection and resource allocation algorithms into base station schedulers. Operators should prioritize scheduling devices that possess both high data quality and favorable channel conditions to maximize learning efficiency per round. Further development should focus on deploying small-scale field pilots in live cellular networks and extending the framework to handle non-orthogonal multiple access, asynchronous model updates, and multi-cell interference environments.
The primary analytical derivations rely on standard convex optimization assumptions regarding the loss functions and assume that corrupted packets are discarded rather than retransmitted. Nevertheless, simulation results on non-convex convolutional neural networks confirm that the optimization framework remains robust and effective in practical deep learning scenarios, providing high confidence in the operational conclusions.
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