5G spatial modeling of personal RF-EMF assessment within aircrafts cabin environments

Recently, new wireless communication systems within aircrafts cabins have drawn higher attention due to the growing demand of passenger services and applications and their corresponding requirements and constraints. In this regard, the fifth generation (5G) of wireless communication becomes an attractive and promising alternative to enable aircraft passengers' comfort and entertainment along the flight, considering its potential benefits in term of high data transfers and low latencies. Nevertheless, general population concern about radio frequency electromagnetic fields (RF-EMF) safety in general and, in particular to the environmental exposure at which we are all exposed in these flights, increases at the same time. Thus, in this work, we present an experimental campaign of measurements for current passengers' environmental exposure assessment, performed in different real generalizable type of flights and aircrafts' cabins, in order to provide current RF-EMF exposure insight within these complex heterogeneous environments. In addition, worst-case uplink 5G scenarios, where all 5G cellular handsets of the passengers operate at the same time, have been simulated by means of an in-house developed 3D Ray Launching (3D-RL) deterministic technique. Before takeoff and after landing, critical scenarios with the aircrafts' doors closed have been selected and assessed considering different types of modeled aircrafts full of passengers, considering 5G frequency range 2 (5G-FR2) operating links. The obtained results show that the operation frequency and the morphology and topology of the aircraft cabin have a great influence in the environmental RF-EMF passengers' spatial distribution and overall exposure, but not exceeding, even in worst case conditions, the international established regulatory limits. © 2022 IEEE.This work was supported by the Ministerio de Ciencia, Innovación y Universidades, Gobierno de España (MCIU/AEI/FEDER, UE) under Project RTI2018-095499-B-C31

Modelling of the Wireless Propagation Characteristics inside Aircraft

Advances in wireless communications technology and more sophisticated portable devices have led to a drastic increase in wireless services and applications. This advancement was made possible through hardware improvements which allow more functions to be implemented in smaller sized devices. The demand for more wireless services has pushed the industry and the research community to increase the communication data rates, connectivity, and availability. The increase in the user base has also brought a decrease in the cost of the services. Although wireless access is becoming available in all public places around the world, this is still not the case for the air passengers who are cut off from wireless services during the duration of the flight. Deployment of wireless technology inside aircraft is still a hot issue due to uncertainties related to interference. Yet, the European Commission has prepared the legal framework for wireless connectivity inside aircraft in April 2008 (Commission, 2008). Aircraft manufacturers will benefit from this technology by exploiting wireless networks to reduce the cable complexity, hence the weight of the aircraft, and by providing new in-flight services, such as online passenger meal selection, service request and video on demand. On the other hand, provisioning of wireless service during flight would profit passengers, since they gain seamless access to common wireless services, such as phone, Internet, and multimedia communications.peer-reviewe

Wireless propagation modelling inside a business jet

Wireless communication on-board aircraft has recently received increased attention as passengers are demanding for seamless office-like communication environments during their flight. Aircraft manufacturers are also interested in this technology to reduce cable complexity and provide new in-flight services. Various technologies are being considered for this purpose, such as IEEE802.11a/b/g. A radio propagation map is necessary to determine the received signal strengths inside the environment and can be obtained either through accurate modelling or through a measurement campaign. A simulation model is more attractive as it can be used to identify ideal antenna locations that maximize coverage at the design stage. Since the business jet market necessitates customized cabin configurations for each customer this will avoid costly measurement campaigns. This work presents a novel simulation model which has been used to characterize propagation characteristics inside a Dassault Aviation business jet. The developed package is based on geometric optics (GO) and adopts ray tracing techniques. Simulation results were compared with actual measurements performed on-board the aircraft with a good correlation between the two. This study takes into account only a static channel whereby all passengers are seated.peer-reviewe

Modeling electromagnetic interference generated by a WLAN system onboard commercial aircraft

This work forms part of the project HIRF SE which is financially supported under the European Union 7th Framework Programme (FP7). The authors are solely responsible for the contents of the paper which does not represent the opinion of the European Commission.The growing demand for the utilization of personal electronic communication devices onboard commercial aircraft necessitates the assurance of safety by airline operators and regulators. This implies that the potential risks posed by the deployment of wireless communication systems on critical aircraft equipment must be carefully assessed and countermeasures taken when required. In this paper, a model based on a ray-tracing algorithm is developed to calculate the electromagnetic interference incident on the fuselage structure of a commercial airline. The source of interference is a 2.4 GHz data communications network. Two scenarios are considered; the first assumes a base station in the centre of the cabin while the second considers four base stations, transmitting at a lower power, distributed along the cabin. The model first determines the propagation map generated by the base stations. These results are used to establish the transmission power required by the personal mobile devices which is then employed to determine the propagation map of each device. The overall electromagnetic interference map incident on the fuselage resulting from the onboard wireless network is generated by vectorially combining the resulting propagation maps. Results for the two scenarios are presented.peer-reviewe

Precise Onboard Aircraft Cabin Localization using UWB and ML

Precise indoor positioning systems (IPSs) are key to perform a set of tasks more efficiently during aircraft production, operation and maintenance. For instance, IPSs can overcome the tedious task of configuring (wireless) sensor nodes in an aircraft cabin. Although various solutions based on technologies of established consumer goods, e.g., Bluetooth or WiFi, have been proposed and tested, the published accuracy results fail to make these technologies relevant for practical use cases. This stems from the challenging environments for positioning, especially in aircraft cabins, which is mainly due to the geometries, many obstacles, and highly reflective materials. To address these issues, we propose to evaluate in this work an Ultra-Wideband (UWB)-based IPS via a measurement campaign performed in a real aircraft cabin. We first illustrate the difficulties that an IPS faces in an aircraft cabin, by studying the signal propagation effects which were measured. We then investigate the ranging and localization accuracies of our IPS. Finally, we also introduce various methods based on machine learning (ML) for correcting the ranging measurements and demonstrate that we are able to localize a node with respect to an aircraft seat with a measured likelihood of 97%

Doctor of Philosophy

dissertationWireless communication has become an essential part of everyday life. The hunger for more data, more phone calls, more video, and more access in more places, including vehicles, is growing massively. Communication in vehicles is particularly challenging because of their extremely high multipath environment. In addition, there is significant interest in reducing the number of wires in vehicles to reduce weight, complexity, maintenance, etc. and replace them with wireless systems. Preliminary research shows that MIMO systems take advantage of the extreme multipath environment found in aircraft and other vehicles and also provides more consistent channel capacity than SISO systems. The purpose of this research was to quantify complex channels (including the aircraft/vehicle environment) and their relation to other environments, evaluate MIMO in aircraft, provide design constraints for accurately modeling complex channels, and provide information to predict optimum antenna type and location to enable communication in aircraft/cars/buses/ships/trains/etc. and other extreme channels. The ability to evaluate and design MIMO technologies from the guidelines in this paper is potentially transformative for aircraft safety - enabling a new generation of location specific monitoring and maintenance. Average measured capacity was found to be between 18 and 21 bits/s/Hz using a 4x4 array of antennas, and had no direct relation to the size of the channel. Site-specific capacity showed a multipath rich channel, varying between 15 to 23 bits/s/Hz. The capacity decreased for increasing measurement distance, with exceptions near reflective objects that increase multipath. Due to these special circumstances for site-specific locations within complex channels, it is recommended that 3D ray tracing be used for modeling as it is more accurate than commonly used statistical models, within 1.1 bits/s/Hz. This showed that our 3D ray tracing is adaptable to various environments and gives a more accurate depiction than statistical models that average channel variations. This comes at the cost of greater model complexity. If increased complexity is not desirable, Nakagami 1.4 could be used as the next most accurate model. Design requirements for modeling different complex channels involve a detailed depiction of channel geometry, including height, width, length, shape (square, cylindrical, slanted walls, etc.), large windows, and reflective objects inside the channel space, especially those near the transmitter. Overall, the multipath rich channel found in vehicles is an excellent environment for MIMO systems. These complex channels can be simulated accurately without measurement and before they are even built using our sitespecific 3D ray tracing software combined with a detailed signal model to incorporate antenna effects

Design and evaluation of wireless dense networks : application to in-flight entertainment systems

Le réseau sans fil est l'un des domaines de réseautage les plus prometteurs avec des caractéristiques uniques qui peuvent fournir la connectivité dans les situations où il est difficile d'utiliser un réseau filaire, ou lorsque la mobilité des nœuds est nécessaire. Cependant, le milieu de travail impose généralement diverses contraintes, où les appareils sans fil font face à différents défis lors du partage des moyens de communication. De plus, le problème s'aggrave avec l'augmentation du nombre de nœuds. Différentes solutions ont été introduites pour faire face aux réseaux très denses. D'autre part, un nœud avec une densité très faible peut créer un problème de connectivité et peut conduire à l'optension de nœuds isolés et non connectes au réseau. La densité d'un réseau est définit en fonction du nombre de nœuds voisins directs au sein de la portée de transmission du nœud. Cependant, nous croyons que ces métriques ne sont pas suffisants et nous proposons une nouvelle mesure qui considère le nombre de voisins directs et la performance du réseau. Ainsi, la réponse du réseau, respectant l'augmentation du nombre de nœuds, est considérée lors du choix du niveau de la densité. Nous avons défini deux termes: l'auto-organisation et l'auto-configuration, qui sont généralement utilisés de façon interchangeable dans la littérature en mettant en relief la différence entre eux. Nous estimons qu'une définition claire de la terminologie peut éliminer beaucoup d'ambiguïté et aider à présenter les concepts de recherche plus clairement. Certaines applications, telles que Ies systèmes "In-Flight Entertainment (IFE)" qui se trouvent à l'intérieur des cabines d'avions, peuveut être considérées comme des systèmes sans fil de haute densité, même si peu de nœuds sont relativement présents. Pour résoudre ce problème, nous proposons une architecture hétérogène de différentes technologies à fin de surmonter les contraintes spécifiques de l'intérieur de la cabine. Chaque technologie vise à résoudre une partie du problème. Nous avons réalisé diverses expérimentations et simulations pour montrer la faisabilité de l'architecture proposée. Nous avons introduit un nouveau protocole d'auto-organisation qui utilise des antennes intelligentes pour aider certains composants du système IFE; à savoir les unités d'affichage et leurs systèmes de commande, à s'identifier les uns les autres sans aucune configuration préliminaire. Le protocole a été conçu et vérifié en utilisant le langage UML, puis, un module de NS2 a été créé pour tester les différents scénarios.Wireless networking is one of the most challenging networking domains with unique features that can provide connectivity in situations where it is difficult to use wired networking, or when ! node mobility is required. However, the working environment us! ually im poses various constrains, where wireless devices face various challenges when sharing the communication media. Furthermore, the problem becomes worse when the number of nodes increase. Different solutions were introduced to cope with highly dense networks. On the other hand, a very low density can create a poor connectivity problem and may lead to have isolated nodes with no connection to the network. It is common to define network density according to the number of direct neighboring nodes within the node transmission range. However, we believe that such metric is not enough. Thus, we propose a new metric that encompasses the number of direct neighbors and the network performance. In this way, the network response, due to the increasing number of nodes, is considered when deciding the density level. Moreover, we defined two terms, self-organization and self-configuration, which are usually used interchangeably in the literature through highlighting the difference ! between them. We believe that having a clear definition for terminology can eliminate a lot of ambiguity and help to present the research concepts more clearly. Some applications, such as In-Flight Entertainment (IFE) systems inside the aircraft cabin, can be considered as wirelessly high dense even if relatively few nodes are present. To solve this problem, we propose a heterogeneous architecture of different technologies to overcome the inherited constrains inside the cabin. Each technology aims at solving a part of the problem. We held various experimentation and simulations to show the feasibility of the proposed architecture

6G Enabled Advanced Transportation Systems

The 6th generation (6G) wireless communication network is envisaged to be able to change our lives drastically, including transportation. In this paper, two ways of interactions between 6G communication networks and transportation are introduced. With the new usage scenarios and capabilities 6G is going to support, passengers on all sorts of transportation systems will be able to get data more easily, even in the most remote areas on the planet. The quality of communication will also be improved significantly, thanks to the advanced capabilities of 6G. On top of providing seamless and ubiquitous connectivity to all forms of transportation, 6G will also transform the transportation systems to make them more intelligent, more efficient, and safer. Based on the latest research and standardization progresses, technical analysis on how 6G can empower advanced transportation systems are provided, as well as challenges and insights for a possible road ahead.Comment: Submitted to an open access journa

Diseño y evaluación de nuevas formas e onda para comunicaciones de alta movilidad

Programa Oficial de Doutoramento en Tecnoloxías da Información e Comunicación en Redes Móbiles. 553V01[Resumo] Os servizos multimedia e de datos experimentaron un crecemento continuo nos últimos anos e espérase que crezan aínda máis nos anos seguintes. A xente está a usar cada vez máis os seus dispositivos móbiles para acceder a servizos baseados en datos para fins relacionados co traballo, entretemento ou socialización en liña. Ademais, as comunicacións masivas de tipo máquina tamén están en ascenso (por exemplo, as comunicacións en transporte e loxística, sensores, Internet das cousas, etc.), e serán moi importantes para a nova xeración de sistemas de comunicacións sen fíos. Para afrontar o aumento esperado no uso de servizos multimedia e baseado en datos, así como para soportar novos casos de uso que hoxe non son posibles, unha nova xeración de redes sen fíos é necesaria. Para iso, espérase que os sistemas de comunicación sen fíos 5G traian as melloras necesarias: maiores taxas de datos, baixas latencias, mellor eficiencia enerxética, alta fiabilidade, etc. O coñecemento das características da canle sen fíos é fundamental para a planificación das redes de comunicación sen fíos e o deseño de transceptores. Como primeiro paso, centramos este traballo na caracterización completa da canle para diferentes escenarios, como son os trens de alta velocidade, metro e comunicacións vehículo a infraestrutura en estradas. A canle caracterizouse mediante a avaliación da relación sinal a ruído, a perda de traxecto (path loss) e os chamados parámetros condensados da canle (por exemplo, o factor K, o perfil potencia-retardo (power delay profile) e a densidade espectral de potencia Doppler. Ademais, para a nova interface aérea das redes 5G, unha das principais cuestións foi a forma de onda a usar. Finalmente, o 3rd Generation Partnership Project (3GPP) decidiu usar a tecnoloxía de multiplexación por división de frecuencias ortogonais (OFDM polas súas siglas en inglés). Isto semella unha elección natural debido ás moitas vantaxes de OFDM e que tamén é a técnica de modulación empregada nas redes 4G. Con todo, nos últimos anos, esquemas multiportadora baseados en bancos de filtros (FBMC polas súas siglas en inglés) recibiron unha grande atención como alternativa a OFDM debido ás súas vantaxes: non utilizan un prefixo cíclico (proporcionan unha maior eficiencia espectral), os usuarios non precisan ser sincronizados no enlace ascendente, e un mellor rendemento teórico en contornas de alta velocidade debido a unha menor interferencia entre portadoras. Neste traballo comparamos experimentalmente o rendemento de FBMC e OFDM en contornas de alta velocidade. Tamén analizamos o rendemento de FBMC e OFDM no caso de uso práctico dun vehículo aéreo lixeiro pilotado remotamente. A maior parte do traballo realizado nesta tese requiriu o deseño e desenvolvemento do chamado GTEC 5G Simulator, que foi usado en conxunto co GTEC Testbed para realizar a maior parte das campañas de medicións e avaliacións de rendemento mediante transmisións polo aire.[Resumen] Los servicios multimedia y basados en datos experimentaron un crecimiento sin interrupciones en los últimos años, y se espera que crezcan aún más en los años siguientes. Las personas utilizan cada vez más sus dispositivos móviles para acceder a los servicios basados en datos con fines relacionados con el trabajo, el entretenimiento o la socialización en línea. Además, las comunicaciones masivas de tipo máquina también están en aumento (por ejemplo, comunicaciones en transporte y logística, sensores, Internet de las cosas, etc.) y serán muy importantes para la nueva generación de sistemas de comunicaciones inalámbricos. Para hacer frente al aumento esperado en el uso de servicios multimedia y basados en datos, así como para soportar nuevos casos de uso que no son posibles hoy en día, se requiere una nueva generación de sistemas inalámbricos. Para esto, se espera que los sistemas de comunicación inalámbrica 5G aporten las mejoras necesarias: mayores tasas de datos, menores latencias, mejor eficiencia energética, alta fiabilidad, etc. El conocimiento de las características del canal inalámbrico es fundamental para la planificación de redes de comunicación inalámbricas y el diseño de transceptores. Como primer paso, centramos este trabajo en la caracterización completa del canal para diferentes escenarios, tales como trenes de alta velocidad, metro y comunicaciones vehículo a infraestructura en carreteras. El canal se caracterizó por medio de la evaluación de la relación señal a ruido, la pérdida de trayecto (path loss) y los llamados parámetros condensados de canal (por ejemplo, el factor K, el perfil potencia-retardo (power delay profile) y la densidad espectral de potencia Doppler). Además, para la nueva interfaz aérea de las redes 5G, una de las preguntas principales ha sido la forma de onda a usar. Finalmente, el 3rd Generation Partnership Project (3GPP) decidió usar la tecnología de multiplexación por división de frecuencias ortogonales (OFDM por sus siglas en inglés). Esta es una elección lógica, debido a las muchas ventajas exhibidas por OFDM y dado que también es la técnica de modulación empleada en las redes 4G. Sin embargo, en los últimos años, los esquemas multiportadora basados en bancos de filtros (FBMC por sus siglas en inglés) han recibido una gran atención como una alternativa a OFDM debido a sus ventajas: no usan un prefijo cíclico (lo que proporciona una mayor eficiencia espectral), los usuarios no necesitan sincronizarse en el enlace ascendente, y un mejor rendimiento teórico en escenarios de alta velocidad debido a una menor interferencia entre subportadoras. En este trabajo comparamos experimentalmente el rendimiento de FBMC y OFDM en entornos de alta velocidad. También analizamos el rendimiento de FBMC y OFDM en el caso de uso práctico de un vehículo aéreo ligero tripulado remotamente. La mayor parte del trabajo llevado a cabo en esta tesis requirió el diseño y desarrollo del denominado GTEC 5G Simulator, que se utilizó junto con el GTEC Testbed para realizar la mayoría de las campañas de medidas y evaluaciones de rendimiento por medio de transmisiones por aire.[Abstract] Multimedia and data-based services experienced a non-stopping growth over the last few years and are expected to grow even more in the following years. People are using more and more their mobile devices to access data-based services for work-related purposes, entertainment or online socialization. Moreover, massive machine-type communications are also on the rise (e.g., transport and logistics communications, sensors, Internet of Things, etc.), and will be very important for the new generation of wireless communication systems. To cope with the expected increase in the usage of multimedia and data-based services, as well as to support new use cases which are not possible today, a new generation of wireless systems is required. For this, 5G wireless communication systems are expected to bring the necessary improvements: higher data rates, lower latencies, better energy efficiency, high reliability, etc. Knowledge of the wireless channel characteristics is fundamental for the planning of wireless communication networks and transceivers design. As a first step, this work centered in the channel characterization for different scenarios such as high-speed trains, subways, and vehicle-to-infrastructure in roads. The channel was characterized by means of assessing the signal-to-noise ratio, the path loss, and the so-called channel condensed parameters (e.g., the K-factor, the power delay profile, and the Doppler power spectral density). Moreover, for the new air interface of 5G networks, one of the main questions was the waveform to be used. Finally, the 3rd Generation Partnership Project (3GPP) decided to use orthogonal frequencydivision multiplexing (OFDM). This seems a natural choice due to the many advantages exhibited by OFDM and it is also the modulation technique employed by 4G networks. However, over the last few years, schemes based on filter bank multicarrier (FBMC) using quadrature amplitude modulation have received a great attention as an alternative to OFDM due to their advantages: they do not use a cyclic prefix (thus providing a higher bandwidth efficiency), users do not need to be synchronized in the uplink, and they achieve a theoretical better performance in high-speed scenarios due to a lower inter-carrier interference. In this work, we have experimentally compared the performance of FBMC versus OFDM in high-speed scenarios. We have also analyzed the performance of FBMC versus OFDM in the practical use case of a lightweight remotely piloted aircraft. The majority of the work carried out in this thesis required the design and development of the so-called GTEC 5G Simulator, which was used in conjunction with the GTEC Testbed to perform most of the measurement campaigns and performance evaluations by means of over-the-air transmissions