Stochastic Geometry Analysis of Interference Coordination in NOMA-based Heterogeneous Networks

TL;DR

This paper uses stochastic geometry to analyze interference coordination methods in NOMA-based heterogeneous networks, comparing coverage and spectral efficiency for FFR and SFR in open and closed access scenarios.

Contribution

It provides a novel stochastic geometry framework to evaluate interference coordination strategies in NOMA heterogeneous networks, including coverage and spectral efficiency analysis.

Findings

Strict FFR yields better coverage in both open and closed access networks.

SFR offers spectral efficiency advantages in open-access networks.

NOMA outperforms OFDMA in spectral efficiency, while OFDMA provides better coverage.

Abstract

In this paper, we present a stochastic geometry-based analysis for the coverage probability of multi-tier heterogeneous networks employing interference coordination for non-orthogonal multiple access (NOMA). Two basic and conventional interference coordination alternatives; strict fractional frequency reuse (FFR) and soft frequency reuse (SFR) are analyzed, and their performance gains on different instances are illustrated. Coverage probability analysis has been extended to that of spectral efficiency for a fair performance evaluation between different FFR methods. The analysis covers both open-access networks with micro- and pico-cells, and closed-access networks with femto-cells. For heterogeneous networks, NOMA is observed to achieve better spectral efficiency than OFDMA, while OFDMA provides better coverage. Both analysis and numerical results reveal that strict FFR provides better coverage while SFR provides spectral efficiency advantage in open-access. However, strict FFR outperforms SFR for both measures in closed-access networks.