Resource Optimization with Load Coupling in Multi-cell NOMA

TL;DR

This paper analyzes resource optimization in multi-cell NOMA networks, proposing an algorithm for joint power, user pairing, and resource allocation that achieves near-optimal performance with fast convergence.

Contribution

It introduces a globally optimal algorithm for joint resource and user pairing optimization in multi-cell NOMA, addressing inter-cell interference challenges.

Findings

Algorithm converges quickly to near-optimal solutions.

NOMA improves resource efficiency and load balancing in multi-cell scenarios.

Demonstrates the effectiveness of load coupling in resource optimization.

Abstract

Optimizing non-orthogonal multiple access (NOMA) in multi-cell scenarios is much more challenging than the single-cell case because inter-cell interference must be considered. Most papers addressing NOMA consider a single cell. We take a significant step of analyzing NOMA in multi-cell scenarios. We explore the potential of NOMA networks in achieving optimal resource utilization with arbitrary topologies. Towards this goal, we investigate a broad class of problems consisting in optimizing power allocation and user pairing for any cost function that is monotonically increasing in time-frequency resource consumption. We propose an algorithm that achieves global optimality for this problem class. The basic idea is to prove that solving the joint optimization problem of power allocation, user pair selection, and time-frequency resource allocation amounts to solving a so-called iterated function without a closed form. We prove that the algorithm approaches optimality with fast convergence. Numerically, we evaluate and demonstrate the performance of NOMA for multi-cell scenarios in terms of resource efficiency and load balancing.