Capacity Evaluation of Aerial LTE Base-Stations for Public Safety Communications Karina Gomez † , Akram Hourani ‡ , Leonardo Goratti † , Roberto Riggio † , Sithamparanathan Kandeepan ‡ and Isabelle Bucaille § † CREATE-NET, via alla Cascata 56D, 38123 Trento, Italy ‡ School of Electrical and Computer Engineering, RMIT University, Melbourne, Australia § Thales Communications & Security, Paris, France Email: {name.surname}@create-net.org; {name.surname}@rmit.edu.au; {name.surname}@thalesgroup.com; Abstract—Aerial-Terrestrial communication networks able to provide rapidly-deployable and resilient communications capable of offering broadband connectivity are emerging as a suitable solution for public safety scenarios. During natural disasters or unexpected events, terrestrial infrastructure can be seriously damaged or disrupted due to physical destruction of network components, disruption in subsystem interconnections and/or network congestion. In this context, Aerial-Terrestrial communi- cation networks are intended to provide temporal large coverage with the provision of broadband services at the disaster area. This paper studies the performance of Aerial UMTS Long Term Evolution (LTE) base stations in terms of coverage and capacity. Network model relies on appropriate channel model, LTE 3GPP specifications and well know schedulers are used. The results show the effect of the temperature, bandwidth, and scheduling discipline on the system capacity while at the same time coverage is investigated in different public safety scenarios. Index Terms—Aerial network infrastructure; emergency com- munications; low altitude platforms; Long Term Evolution (LTE); I. I NTRODUCTION During critical situations, communications among first re- sponders of different public safety agencies are hampered by interoperability problems. In Europe, incompatibility is mainly due to the lack of a harmonized approach to frequency plan- ning and standards for public safety communications. Thus the possibility to reuse commercial radio technologies for public safety communications is emerging as a suitable solution to solve interoperability issues. Furthermore, first responders need a better blend of reliability and multimedia capability, which can be provided by 4G-LTE cellular technology and its advanced version LTE-A. Massive destruction of communication infrastructures caused by natural disasters or unexpected events might also hamper the communication of the public safety agencies over a disaster area. To fulfill the requirement of deploying flexible and rapidly deployable resilient communication infrastructures for public safety, the main goal of the FP7 ABSOLUTE project [1] is to design and validate an innovative holistic network architecture ensuring dependable communication ser- vices based on the following main features: rapid deployment, flexibility, scalability, resilience and provision of inter-operable broadband services. In this paper, we studied a holistic and rapidly deploy- able mobile network architecture based on the hybrid aerial- terrestrial combination designed within ABSOLUTE project. The proposed architecture opportunistically combines terres- trial, aerial and satellite communication segments. Focusing on the aerial segment, we investigate the performance of Aerial LTE base stations (AeNB) deployed on airborne platforms in terms of achievable cell coverage and channel capacity for a 4G-LTE system in Frequency-Division Duplex (FDD) mode. In this context, we analyze the impact of several parameters such as temperature, bandwidth, scheduling disciplines and propagation environment on the aforementioned AeNBs cov- erage and capacity in scenarios modeled whereby appropriate channel model for air-to-ground propagation. Moreover we resort to well-known schedulers available in the literature. The remainder of the paper is organized as follows. In Section 2 we summarize the related work, and in Section 3 we describe a Aerial-Terrestrial network architecture. In Section 4 the system model is discussed and Section 5 details the performance evaluation. Finally, we provide concluding remarks of the paper in Section 6. II. RELATED WORK Few papers investigate the use of Low Altitude Platforms (LAP) for provisioning radio connectivity that specify the communication technologies and their performance. Authors in [2] investigate the feasibility of deploying High Altitude Platforms (HAP) carrying WiFi equipment for supporting mul- timedia broadcast/multicast services. In [3], the HAP–based emergency communications network for delivering emergency calls and multimedia broadcast services are investigated. The proposed network architecture consists of a two–hop relay system based on WiMAX stations. While, the use of balloons combining IEEE 802.11 technology for building an ad hoc communication is investigated in [4]. The main objective of the proposed network is to support emergency medical services inside incident areas. In our previous work [5], we investigated the performance of 4G LTE base stations embedded on aerial platforms in a Time-Division Duplex (TDD) configuration mode. We studied the effect of platform altitude and mobility on cell coverage and channel capacity.