Learning for Cross-Layer Resource Allocation in MEC-Aided Cell-Free Networks
Chong Zheng, Shiwen He, Yongming Huang, Tony Q. S. Quek
TL;DR
This work tackles cross-layer resource allocation in MEC-aided CF networks by jointly optimizing subcarrier allocation and beamforming to maximize the weighted sum rate $R_{\text{WSR}}=\sum_i \alpha_i r_i$. It introduces a multi-task learning formulation that recasts the optimization into $I+B+1$ self-supervised tasks and proposes centralized (CMTSSL) and distributed (DMTSSL) multi-task learners, guided by novel NFL and EL losses with adaptive uncertainty weights. A distance-aware transfer learning (DATL) mechanism is added to handle dynamic addition of SBSs with negligible cost, leveraging knowledge from the nearest existing SBS. Numerical results in a 3GPP 38.901 UMa scenario show that the proposed methods surpass baselines in sum-rate performance while offering scalable complexity and robustness to label noise and network dynamics. The approach provides a practical pathway to real-time, scalable cross-layer optimization in future MEC-aided wireless networks.
Abstract
Cross-layer resource allocation over mobile edge computing (MEC)-aided cell-free networks can sufficiently exploit the transmitting and computing resources to promote the data rate. However, the technical bottlenecks of traditional methods pose significant challenges to cross-layer optimization. In this paper, joint subcarrier allocation and beamforming optimization are investigated for the MEC-aided cell-free network from the perspective of deep learning to maximize the weighted sum rate. Specifically, we convert the underlying problem into a joint multi-task optimization problem and then propose a centralized multi-task self-supervised learning algorithm to solve the problem so as to avoid costly manual labeling. Therein, two novel and general loss functions, i.e., negative fraction linear loss and exponential linear loss whose advantages in robustness and target domain have been proved and discussed, are designed to enable self-supervised learning. Moreover, we further design a MEC-enabled distributed multi-task self-supervised learning (DMTSSL) algorithm, with low complexity and high scalability to address the challenge of dimensional disaster. Finally, we develop the distance-aware transfer learning algorithm based on the DMTSSL algorithm to handle the dynamic scenario with negligible computation cost. Simulation results under $3$rd generation partnership project 38.901 urban-macrocell scenario demonstrate the superiority of the proposed algorithms over the baseline algorithms.
