On the Performance of Aerial LTE Base-Stations for Public Safety and Emergency Recovery Karina Gomez † , Tinku Rasheed † , Laurent Reynaud ‡ and Sithamparanathan Kandeepan § † CREATE-NET, via alla Cascata 56D, 38123 Trento, Italy ‡ Orange Labs, 2 Avenue Pierre Marzin, 22307 Lannion, France § School of Electrical and Computer Engineering, RMIT University, Melbourne, Australia Email: {kgomez,trasheed}@create-net.org; laurent.reynaud@orange.com; kandeepan@ieee.org Abstract—Recent events have shown that in the aftermath of an unexpected incident, communication infrastructures play an important role in supporting critical services. Airborne communication networks have been recently studied for the provision of wireless communication services and it is a promis- ing candidate for rapidly deployable and resilient emergency networks. However, the choice of communication technologies from Aerial platforms is a challenging issue and depends on a variety of factors including platform payload capacity, coverage and capacity requirements, to name a few. In this paper, we investigate the performance of 4G LTE-WiFi multimode base stations deployed on airborne platforms which provides coverage for first responders during emergencies. We present an adapted simulation model for the analysis of hybrid aerial-terrestrial systems and study the impact of platform elevation and mobility on the cell coverage and channel capacity. Performance analysis with a platform deployment of a single Aerial Base Station (eNodeB) corroborates that airborne units with 4G commu- nication capabilities are very promising candidates for robust communication links during emergency relief operations. Index Terms—Aerial network infrastructure; emergency com- munications; low altitude platforms; Long Term Evolution (LTE); I. I NTRODUCTION Recent events have shown that in the aftermath of an unex- pected event, communication infrastructures play an important role in supporting critical services such as emergency recovery and post-disaster operations, infrastructure restoration, etc [1]. Current mission critical systems, including Public Protection and Disaster Relief (PPDR) communication systems, are lim- ited in terms of network capacity and coverage. They are not designed for or suitable to address large scale emergency communication needs in a disaster aftermath. PPDR systems are also limited by interoperability barriers, the technological gap with commercial technologies and evolving standards. Aerial communication networks have been recently studied for the provision of wireless communication services and have continually attracted significant interest from government, in- dustry and academia [2]. While much of the original efforts have focused on developing long endurance High Altitude Platforms (HAP) operating at altitudes of about 17-25 km, in the recent years, many other types of aerial platforms, either aerostats or aerodynes, have been developed to fly at lower altitudes. Those platforms, gathered under the denomination of Low Altitude Platforms (LAP) are increasingly believed to offer the potentiality to effectively complement conventional satellite or terrestrial telecommunication infrastructures, as an- nounced by Google [3]. For example, the DACA (Deployable Aerial Communication Architectures) architecture proposed by the FCC in the US explores the feasibility to deploy aerial platforms during emergency situations to restore critical communications [6]. While LAPs based on UAVs are subject to several research efforts ranging from robotics to remote sensing and surveil- lance applications, provisioning of broadband communications using low flying LAPs have not been well investigated, mainly due to the associated challenges with payload capacity and power demands [4], [5]. Recently, a hybrid approach, proposed in [7] has the main goal to demonstrate the high-capacity, low- latency and coverage capabilities of LTE-A solutions adapted for rapidly deployable broadband emergency communications through embedded onboard LAPs. To model the system level parameters in a Hybrid Aerial- Terrestrial Network and to analyse the LTE performance requires a completely developed LTE system simulator. There are several LTE simulators available in the academic commu- nity which are open source [8], [9], [11], but such simulators and associated models are not totally applicable to Aerial- Terrestrial communication environments. In this paper, we propose a holistic and rapidly deployable mobile network architecture based on a hybrid aerial-terrestrial approach, which is flexible to be adapted to different scenarios based on the characteristics of the aerial platforms and the choice of deployment of the LTE-specific system components [10]. The main contributions of this paper are: • We present an adapted simulation model for the analysis and complete performance verification of hybrid Aerial- Terrestrial systems based on 4G LTE technology. • We investigate the performance of multimode 4G LTE- WiFi base stations deployed on airborne platforms which provide coverage for first responders during emergencies. • We analyze the impact of platform elevation and mobility on channel stability which provides several insights into further investigation into the resilience and scalability aspects of the proposed architecture.