Partially-Distributed Resource Allocation in Small-Cell Networks

TL;DR

This paper introduces a hierarchical, partially decentralized resource allocation scheme for large-scale small-cell OFDMA networks, effectively managing interference and load demand with reduced complexity.

Contribution

It presents a novel four-phase hierarchical algorithm that dynamically allocates resources considering user load and mobility, improving over fixed schemes.

Findings

Effective interference management demonstrated through simulations

Dynamic resource allocation adapts to user mobility

Hierarchical scheme reduces computational complexity

Abstract

We propose a four-stage hierarchical resource allocation scheme for the downlink of a large-scale small-cell network in the context of orthogonal frequency-division multiple access (OFDMA). Since interference limits the capabilities of such networks, resource allocation and interference management are crucial. However, obtaining the globally optimum resource allocation is exponentially complex and mathematically intractable. Here, we develop a partially decentralized algorithm to obtain an effective solution. The three major advantages of our work are: 1) as opposed to a fixed resource allocation, we consider load demand at each access point (AP) when allocating spectrum; 2) to prevent overloaded APs, our scheme is dynamic in the sense that as the users move from one AP to the other, so do the allocated resources, if necessary, and such considerations generally result in huge computational complexity, which brings us to the third advantage: 3) we tackle complexity by introducing a hierarchical scheme comprising four phases: user association, load estimation, interference management via graph coloring, and scheduling. We provide mathematical analysis for the first three steps modeling the user and AP locations as Poisson point processes. Finally, we provide results of numerical simulations to illustrate the efficacy of our scheme.