Romain Hermenier

Airborne Base Stations for Emergency and Temporary Events

This paper introduces a rapidly deployable wireless network based on Low Altitude Platforms and portable land units to support disaster-relief activities, and to extend capacity during temporary mass events. The system integrates an amalgam of radio technologies such as LTE, WLAN and TETRA to provide heterogeneous communications in the deployment location. Cognitive radio is used for autonomous network configuration. Sensor networks monitor the environment in real-time during relief activities and provide distributed spectrum sensing capacities. Finally, remote communications are supported via S-band satellite links.

Rapidly Deployable Network for Tactical Applications: Aerial Base Station with Opportunistic Links for Unattended and Temporary Events ABSOLUTE Example

Hybrid aerial and terrestrial communication systems have recently emerged for public safety communications and tactical applications due to their fast deployment and large coverage capabilities. A key question is the choice of the communication payload depending on the aerial platform being deployed. Indeed, this payload depends on several factors including the aerial platform size, the payload weight as well as coverage and capacity requirements. This article analyses different options and presents the work which is ongoing in ABSOLUTE (Aerial Base Station with Opportunistic Links for Unattended and Temporary Events) European project. It first summarizes the outputs of the user requirements as developed in ABSOLUTE. Then, different aerial platforms and associated payload for a rapidly deployable tactical network are discussed, and the hybrid aerial and terrestrial communication system as developed in the project is presented. Finally it presents research topics and remaining challenges are highlighted.

Clustering approach for aerial base-station access with terrestrial cooperation

In this paper we propose a clustering mechanism for improved energy efficiency in aerial based access systems suitable for disaster recovery scenarios and large scale public events. The aerial base station is a low altitude platform (LAP) station that provides access to several terrestrial nodes on the ground over a prescribed coverage area. The terrestrial nodes are battery operated power constrained terminals that have got no base station access except for the LAP. Since the aerial uplink is a high cost energy link we propose a cluster based approach for LAP access. The proposed clustering mechanism is simulated and is compared with the well known clustering technique HEED for energy efficiency. Results show that the proposed clustering technique improves the energy efficiency compared to the non-clustering situation as well as to the HEED clustering technique.

Aerial base stations with opportunistic links for next generation emergency communications

Rapidly deployable and reliable mission-critical communication networks are fundamental requirements to guarantee the successful operations of public safety officers during disaster recovery and crisis management preparedness. The ABSOLUTE project focused on designing, prototyping, and demonstrating a high-capacity IP mobile data network with low latency and large coverage suitable for many forms of multimedia delivery including public safety scenarios. The ABSOLUTE project combines aerial, terrestrial, and satellites communication networks for providing a robust standalone system able to deliver resilience communication systems. This article focuses on describing the main outcomes of the ABSOLUTE project in terms of network and system architecture, regulations, and implementation of aerial base stations, portable land mobile units, satellite backhauling, S-MIM satellite messaging, and multimode user equipments.

A delay model for satellite constellation networks with inter-satellite links

Within this paper we examine a non-geostationary satellite constellation network with inter-satellite links (ISLs) for global air traffic control (ATC) and air passenger communication (APC). More specifically, an analysis is done to investigate the impacts of different routing policies on the end-to-end delay, and a general model describing the delays is developed. All considerations are based on a Galileo-like satellite constellation network and real global flight data of all commercial flights during one day

Machine‐to‐machine communications via airliners

Whenever we look to the blue sky, condensation trails or even an aircraft can be spotted in most regions of the world. Therefore, the question of frequency of aircraft visibility is present. This is extrapolated to the novel problem of a communications infrastructure via airliners: would it be possible to establish a communications service on ground, for example, machine-to-machine service, using schedules airliners as relay stations? Coverage analysis, first access and coding strategies are given stimulating further research activities and ideas in this new area.

On the Behavior of RObust Header Compression U-mode in Channels with Memory

The existing studies of RObust Header Compression (ROHC) have provided some understanding for memoryless channel, but the behavior of ROHC for correlated wireless channels is not well investigated in spite of its practical importance. In this paper, the dependence of ROHC against its design parameters for the Gilbert Elliot channel is studied by means of three analytical models. A first more elaborated approach accurately predicts the behavior of the protocol for the single RTP flow profile, while a simpler, analytically tractable model yields clear and insightful mathematical relationships that explain the qualitative trends of ROHC. The results are validated against a real world implementation of this protocol. Moreover, a third model studies also the less conventional yet practically relevant setting of multiple RTP flows.

A simple analytical model for Robust Header Compression in correlated wireless links

Robust Header Compression (ROHC) has been successfully included in some wireless standards in order to reduce the excessive IP overhead for small packets, for instance Voice over IP frames. So far, there is limited understanding on how the ROHC performance depends on the design parameters and the characteristics of the wireless channel. In this paper we propose an analytical model that provides simple expressions for the probability of losing synchronization as a function of the mentioned parameters, and also yields insightful relationships between the design variables and the desired system performance. The results are validated against sophisticated and realistic models of ROHC.

Satellite constellation networks for aeronautical communication: traffic modelling and link load analysis

The authors examine two different non-geostationary satellite constellation networks with inter-satellite links for global air traffic control and air passenger communication. After developing a traffic model for aeronautical communication services, the authors derive bandwidth requirements for such a global system. The influence of different routing policies is discussed and they show that link loads are comparable for both medium earth orbit and low earth orbit constellations. All considerations are based on real global flight data of all commercial flights during 1 day.

Global Maritime Surveillance by Airliner-Based AIS Detection: Preliminary Analysis

Demands on security, safety, and environmental protection in worldwide shipping are steadily increasing. Shipboard broadcast transponders based on the Automatic Identification System (AIS) can be easily detected close to coastal or waterway areas. Satellite-based AIS receivers detect globally but are limited in high-density traffic areas. This paper investigates the challenges and performance of AIS detection on aircraft at altitudes between 8 500 m and 10 000 m. During flight trials over sea and land, AIS signals were recorded. Post-processing of the recorded data allows the evaluation but also faces challenges due to the nature of overlapping AIS signals at the aircraft. A comparison of detected signals at the aircraft with received AIS signals on the ground is given, including the evaluation of the reception footprint of the aircraft. Finally, a concept for worldwide AIS detection via airliners is presented. The study shows the potential for global complementary surveillance coverage via airliner-based AIS detection.