Interference Coordination for Aerial and Terrestrial Nodes in Three-Tier LTE-Advanced HetNet

TL;DR

This paper investigates interference management in a three-tier LTE-Advanced HetNet with UAVs as both user equipment and base stations, using simulations to optimize parameters and improve spectral efficiency and coverage.

Contribution

It provides system-level insights and optimization strategies for integrating UAVs into LTE-Advanced HetNets, focusing on interference coordination and cell range expansion techniques.

Findings

Reduced power subframes outperform almost blank subframes in spectral efficiency.

Optimized ICIC and CRE parameters significantly improve coverage probability.

3D beamforming enhances UAV integration in HetNets.

Abstract

Integrating unmanned aerial vehicles (UAVs) as user equipment (UE) and base-stations (BSs) into an existing LTE-Advanced heterogeneous network (HetNet) can further enhance wireless connectivity and support emerging services. However, this would require effective configuration of system-level design parameters for interference management. This paper provides system-level insights into a three-tier LTEAdvanced air/ground HetNet, wherein the UAVs are deployed both as BSs and UEs, and co-exist with existing terrestrial nodes. Moreover, this HetNet leverages on cell range expansion (CRE), intercell interference coordination (ICIC), 3D beamforming, and enhanced support for UAVs. Through Monte-Carlo simulations, we compare system-wide fifth percentile spectral efficiency (5pSE) and coverage probability for different ICIC techniques, while jointly optimizing the ICIC and CRE parameters. Our results show that reduced power subframes defined in 3GPP Rel-11 can provide considerably better 5pSE and coverage probability than the 3GPP Rel-10 with almost blank subframes.