91 research outputs found

    Cooperative Radio Communications for Green Smart Environments

    Get PDF
    The demand for mobile connectivity is continuously increasing, and by 2020 Mobile and Wireless Communications will serve not only very dense populations of mobile phones and nomadic computers, but also the expected multiplicity of devices and sensors located in machines, vehicles, health systems and city infrastructures. Future Mobile Networks are then faced with many new scenarios and use cases, which will load the networks with different data traffic patterns, in new or shared spectrum bands, creating new specific requirements. This book addresses both the techniques to model, analyse and optimise the radio links and transmission systems in such scenarios, together with the most advanced radio access, resource management and mobile networking technologies. This text summarises the work performed by more than 500 researchers from more than 120 institutions in Europe, America and Asia, from both academia and industries, within the framework of the COST IC1004 Action on "Cooperative Radio Communications for Green and Smart Environments". The book will have appeal to graduates and researchers in the Radio Communications area, and also to engineers working in the Wireless industry. Topics discussed in this book include: • Radio waves propagation phenomena in diverse urban, indoor, vehicular and body environments• Measurements, characterization, and modelling of radio channels beyond 4G networks• Key issues in Vehicle (V2X) communication• Wireless Body Area Networks, including specific Radio Channel Models for WBANs• Energy efficiency and resource management enhancements in Radio Access Networks• Definitions and models for the virtualised and cloud RAN architectures• Advances on feasible indoor localization and tracking techniques• Recent findings and innovations in antenna systems for communications• Physical Layer Network Coding for next generation wireless systems• Methods and techniques for MIMO Over the Air (OTA) testin

    Cooperative Radio Communications for Green Smart Environments

    Get PDF
    The demand for mobile connectivity is continuously increasing, and by 2020 Mobile and Wireless Communications will serve not only very dense populations of mobile phones and nomadic computers, but also the expected multiplicity of devices and sensors located in machines, vehicles, health systems and city infrastructures. Future Mobile Networks are then faced with many new scenarios and use cases, which will load the networks with different data traffic patterns, in new or shared spectrum bands, creating new specific requirements. This book addresses both the techniques to model, analyse and optimise the radio links and transmission systems in such scenarios, together with the most advanced radio access, resource management and mobile networking technologies. This text summarises the work performed by more than 500 researchers from more than 120 institutions in Europe, America and Asia, from both academia and industries, within the framework of the COST IC1004 Action on "Cooperative Radio Communications for Green and Smart Environments". The book will have appeal to graduates and researchers in the Radio Communications area, and also to engineers working in the Wireless industry. Topics discussed in this book include: • Radio waves propagation phenomena in diverse urban, indoor, vehicular and body environments• Measurements, characterization, and modelling of radio channels beyond 4G networks• Key issues in Vehicle (V2X) communication• Wireless Body Area Networks, including specific Radio Channel Models for WBANs• Energy efficiency and resource management enhancements in Radio Access Networks• Definitions and models for the virtualised and cloud RAN architectures• Advances on feasible indoor localization and tracking techniques• Recent findings and innovations in antenna systems for communications• Physical Layer Network Coding for next generation wireless systems• Methods and techniques for MIMO Over the Air (OTA) testin

    Broadband wireless communication systems for high mobility scenarios

    Get PDF
    Programa Oficial de Doutoramento en Tecnoloxías da Información e Comunicación en Redes Móbiles. 553V01[Resumen] A lo largo de los últimos años el uso de servicios multimedia y, en general, basados en el acceso a información “en la nube”, experimentó un auge sin precedentes. A diferencia respecto del pasado, los usuarios no solamente acceden a los servicios desde una ubicación estática; por contra, navegan libremente entre distintos lugares al tiempo que acceden, desde sus dispositivos móviles, a servicios en la nube. Debido al ritmo de vida actual, el tránsito entre zonas rurales y ciudades también se incrementó de modo notable, al ubicarse la mayor parte de los lugares de trabajo en ciudades o en sus respectivos entornos. Durante los períodos de transporte, cada vez más, los pasajeros emplean sus dispositivos móviles para trabajar, acceder a redes sociales o como dispositivos de entretenimiento. En la actualidad, GSM for Railways (GSM-R) es el sistema de comunicaciones más empleado entre los trenes y el resto de elementos involucrados en la infraestructura ferroviaria. Sin embargo, GSM-R no es adecuado para proporcionar servicios avanzados, tales como el control de piloto automático, así como para sustentar transmisiones de banda ancha a los operadores ferroviarios o proporcionar servicios de valor añadido a los pasajeros. Centrándonos en el mercado de dispositivos de comunicaciones de ámbito general, la explosión de usuarios y servicios multimedia de los últimos años motivó la migración, primero a las redes de tercera generación y, seguidamente, a las de cuarta, con Long Term Evolution (LTE) a la cabeza. Así, parece natural plantear a LTE como la tecnología candidata para la sustitución de GSM-R. En el presente trabajo se lleva a cabo un completo estudio de las prestaciones de sistemas de comunicaciones inalámbricas de banda ancha en vehículos de alta velocidad basado en campañas de medidas llevadas a cabo en entornos reales. Se estudió especialmente el caso de comunicaciones LTE en trenes de alta velocidad. Se proponen técnicas de reducción del coste y complejidad en relación a las evaluaciones en entornos de alta velocidad y se prueba su funcionamiento de modo analítico, mediante simulación y empíricamente. De cara a validar los desarrollos presentados en esta tesis en relación a los últimos avances en materia comunicaciones, se consideraron también las más novedosas propuestas para sistemas de quinta generación, actualmente aún en fase de definición. Es más, se evaluaron, tanto mediante simulación como vía medidas en entornos de alta velocidad, las prestaciones brindadas por las propuestas para sistemas de comunicaciones de quinta generación. El código fuente del GTEC Testbed y del GTEC 5G Simulator está disponible públicamente bajo la licencia GPLv3 en https://bitbucket.org/tomas_bolano/gtec_testbed_public.git.[Resumo] Ao longo dos últimos anos o uso de servizos multimedia e, en xeral, baseados no acceso a información contida “na nube”, experimentou un auxe sen precedentes. A diferencia respecto do pasado, os usuarios non soamente acceden aos servizos dende unha ubicación estática; pola contra, navegan libremente entre distintos lugares ao tempo que acceden, dende os seus dispositivos móbiles, a servizos na nube. Debido ao ritmo de vida actual, o tránsito entre zonas rurais e cidades tamén se incrementou de modo notable, ao ubicarse a maior parte dos lugares de traballo nas cidades ou nas súas respectivas contornas. Durante os períodos de transporte, cada vez máis, os pasaxeiros empregan os seus dispositivos móbiles para traballar, acceder a redes sociais ou como ferramenta de entretemento. O factor común da maior parte dos servizos típicamente empregados é a súa dependencia respecto do acceso á rede. Na actualidade, GSM for Railways (GSM-R), baseado no xa vetusto GSM, é o sistema de comunicacións máis empregado entre os trens e o resto dos elementos involucrados na infraestrutura ferroviaria. Sen embargo, GSM-R non é axeitado para proporcionar servizos avanzados, tales como o control de piloto automático, así como para sustentar transmisións de banda ancha aos operadores ferroviarios ou proporcionar servizos de valor engadido aos pasaxeiros. Botando unha ollada ao mercado de dispositivos de comunicacións de ámbito xeral, a explosión de usuarios e servizos multimedia dos últimos anos motivou a migración, primeiro ás redes de terceira xeración e, seguidamente, ás de cuarta, con Long Term Evolution (LTE) á cabeza. Así, parece natural plantexar LTE como o candidato para a substitución de GSM-R. No presente traballo lévase a cabo un completo estudo das prestacións de sistemas de comunicacións sen fíos de banda ancha en vehículos de alta velocidade baseado en campañas de medidas levadas a cabo en contornas reais de alta velocidade. Estudouse especialmente o caso de comunicacións LTE en trens de alta velocidade. Propóñense técnicas de redución de custo e complexidade en relación ás avaliacións en contornas de alta velocidade e valídase o seu funcionamento de xeito analítico, mediante simulación e empíricamente. Os desenvolvementos presentados nesta tese foron validados para os sistemas de quinta xeración, aínda en fase de definición. Avaliáronse, mediante simulación e experimentalmente en contornas de alta velocidade, as prestacións brindadas polas propostas para sistemas de comunicacións de quinta xeración. O código fonte do GTEC Testbed e do GTEC 5G Simulator está dispoñible públicamente baixo a licenza GPLv3 en https://bitbucket.org/tomas_bolano/gtec_testbed_public.git.[Abstract] Over the last few years multimedia and data-based services experienced a non-stopping growth. Unlike before, people do not use the services only from a static location, but they are continuously on the move between different scenarios, using their mobile devices to access data-based services. In parallel, commuter traffic from rural areas is also rising, since most of work places are in and around cities. During transportation, people intensively employ mobile devices to work, access to social networks, or as an entertainment means. Internet access is required for most of these services. Currently, GSM for Railways (GSM-R), which is based on the Global System for Mobile Communications (GSM), is the most widely used communication system between trains and the elements involved in operation, control, and intercommunication within the railway infrastructure. However, GSM-R is not well suited for supporting advanced services such as automatic pilot applications or provisioning broadband services to the train staff and passengers. Besides trains, the increasing number of broadband services available for mobile devices motivated the migration from third-generation mobile networks to fourth generation ones, mainly Long Term Evolution (LTE). Therefore, LTE seems to be a good candidate to substitute the GSM as the fundamental technology for railway communications. In this work a complete study on the performance of high capacity broadband wireless communication systems for high speed vehicles is presented, based on measurement campaigns in actual high speed environments. Special attention is devoted to the case of LTE in high speed trains. Techniques to greatly reduce the cost and complexity of measurement-based evaluations in high speed scenarios are proposed and proven to work analytically, by means of simulations and by measurements in actual high speed environments. With the aim of checking the validity of the findings of this work for the latest advances in wireless communication systems, proposals for fifth generation (5G) communication systems, currently still under definition, were also considered. Moreover, the performance of the proposals for 5G communication systems was also evaluated by means of simulations as well as by measuring in high speed environments. The source code of both the GTEC Testbed and the GTEC 5G Simulator is publicly available under the GPLv3 license at https://bitbucket.org/tomas_bolano/gtec_testbed_public.git

    Over-The-Air (OTA) Measurement Method for MIMO-enabled Mobile Terminals

    Get PDF
    Over-The-Air (OTA) test methods for performance evaluation play an important role in the certification process of commercial User Equipment (UE) and for admission of UE to cellular networks. Novel OTA test methods and metrics are required for state-of-the-art mobile communication standards such as 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) due to the extensive use of Multiple Input – Multiple Output (MIMO) transmission techniques. The variety of different MIMO operating modes and the almost unlimited choice of possible multi-path channel conditions under which UE performance may be evaluated is not accounted for by established Single Input – Single Output (SISO) OTA performance metrics like Total Isotropic Sensitivity (TIS) and Total Radiated Power (TRP). As pointed out in this dissertation, meaningful metrics and cost effective, low complexity measurement methods can nevertheless be derived by focusing on characterization of the physical attributes of UE and by adopting statistical metrics. Starting from an overview of existing OTA measurement methods for SISO devices, extensions which are necessary to evaluate UE performance in the different MIMO operating modes which are foreseen in the 3GPP LTE standard are discussed. Relations between UE implementation attributes and the UE performance which is observed in different MIMO operating modes are derived using generic antenna and propagation models. Based on these models existing proposals for OTA test methods are reviewed. Their suitability and the relevance of different implementation aspects therein are discussed. The main result of this dissertation is a novel MIMO OTA test plan which focuses on the characterization of relevant UE attributes and meets the goals of low complexity and high reproducibility. Two complementary metrics and corresponding measurement procedures for evaluation of MIMO OTA performance are developed in order to address the diversity of possible propagation scenarios. The theoretical results are supported by extensive measurements using preliminary implementations of the proposed method. These include results from an international round-robin measurement campaign for High-Speed Packet Access (HSPA) devices and results from a variety of measurements on LTE devices which were performed at different test sites. Additional validation and investigation of specific aspects is addressed by simulation.Over-The-Air (OTA) Messverfahren für MIMO-fähige mobile Endgeräte Over-The-Air (OTA) Testverfahren für die Bewertung der Qualität von kommerziellen Endgeräten (User Equipment (UE)) sind von großer Bedeutung im Rahmen der Zertifizierung von UE und der Zulassung zu Mobilfunknetzwerken. Im Zusammenhang mit den aktuellen mobilen Kommunikationsstandards, wie etwa dem 3rd Generation Partnership Project (3GPP) Standard Long Term Evolution (LTE), sind, aufgrund der Verwendung von Multiple Input – Multiple Output (MIMO) Übertragungstechniken neuartige Metriken und Messverfahren erforderlich. Die Vielfalt der verschiedenen MIMO Betriebsarten und die fast unbegrenzte Auswahl möglicher Kanalbedingungen (Mehrwegeausbreitung), unter denen die Qualität von UE bewertet werden kann, wird von den etablierten Single Input – Single Output (SISO) OTA Metriken Total Isotropic Sensitivity (TIS) und Total Radiated Power (TRP) nicht abgedeckt. Wie in dieser Arbeit gezeigt wird, lassen sich durch Fokussierung auf die Charakterisierung der maßgeblichen physikalischen Eigenschaften des UE sowie Einführung statistischer Metriken dennoch aussagekräftige Metriken und kostengünstige Messmethoden geringer Komplexität gewinnen. Ausgehend von einem Überblick existierender OTA Testverfahren für SISO Endgeräte werden die Erweiterungen diskutiert, die notwendig sind, um die Qualität von Endgeräten unter den verschiedenen MIMO Betriebsarten, die der Standard 3GPP LTE vorsieht, bewerten zu können. Unter Verwendung generischer Modelle für Antennen und Ausbreitungsszenarien werden Beziehungen zwischen den Eigenschaften von UE und der in den verschiedenen MIMO Betriebsarten zu beobachtenden Emfangsqualität abgeleitet. Darauf aufbauend werden existierende Vorschläge für OTA Testverfahren untersucht. Deren Eignung und die Relevanz der verschiedener Aspekte in ihrer Implementierung werden diskutiert. Das wesentliche Ergebnis dieser Arbeit ist ein neuartiges MIMO OTA Testkonzept, bei dem die Charakterisierung der relevanten UE Eigenschaften im Mittelpunkt steht und welches den Anforderungen geringer Komplexität und hoher Reproduzierbarkeit genügt. Es werden zwei einander ergänzende Metriken definiert und die zugehörigen Testvorschriften vorgestellt, mit dem Ziel die Vielfalt der möglichen Übertragungszenarien abzudecken. Der theoretische Herleitungen werden durch umfangreiche Messungen mit vorläufigen Implementierungen des vorgeschlagenen Testkonzeptes unterstüzt. Dazu gehören Ergebnisse aus einer internationalen Round-Robin-Messkampagne für High-Speed Packet Access (HSPA)-Endgeräte und Ergebnisse aus zahlreichen Messungen an LTE Endgeräten, die in verschiedenen Laboren durchgeführt wurden. Eine Zusätzliche Validierung sowie die Untersuchung einiger spezifischer Aspekte erfolgt mit Hilfe von Simulationen

    Real-time Monitoring of Low Voltage Grids using Adaptive Smart Meter Data Collection

    Get PDF

    Detection of OFDM Signals Using Pilot Tones and Applications to Spectrum Sensing for Cognitive Radio Systems

    Get PDF
    Nowadays there are an increasing number of wireless devices which support wireless networking and the need for higher data rate communication is increasing rabidly. As more and more systems go wireless, approaching technologies will face spectral crowding and existence of wireless devices will be an important issue. Because of the limited bandwidth availability, accepting the request for higher capacity and data rates is a challenging task, demanding advanced technologies that can offers new methods of using the available radio spectrum. Cognitive radio introduces a key solution to the spectral increasing issue by presenting the opportunistic usage of spectrum that is not heavily occupied by licensed users. It is a latest idea in wireless communications systems which objective to have more adaptive and aware communication devices which can make better use of available natural resources. Cognitive radio appears to be an attractive solution to the spectral congestion problem by introducing the notion of opportunistic spectrum use. Cognitive radios can operate as a secondary systems on top of existence system which are called primary (or licensed) systems. In this case, secondary (cognitive) users need to detect the unused spectrum in order to be able to access it. Because of its many advantages, orthogonal frequency division multiplexing (OFDM) has been successfully used in numerous wireless standards and technologies. It\u27s shown that OFDM will play an important role in realizing the cognitive radio concept as well by providing a proven, scalable, and adaptive technology for air interface. Researches show that OFDM technique is considered as a candidate for cognitive radio systems. The objective of this dissertation is to explore detecting of OFDM modulated signals using pilot tones information. Specifically we applying Time-Domain Symbol Cross-Correlation (TDSC) method in the confect of actual 4G wireless standards such as WIMAX and LTE. This detection is only based upon the knowledge of pilot structures without knowledge of received signal so that, it can be performed on every portion of the received signal. The approach induces Cross-Correlation between pilots subcarriers and exploits the deterministic and periodic characteristics of pilot mapping in the time frequency domain

    Software Defined Applications in Cellular and Optical Networks

    Get PDF
    abstract: Small wireless cells have the potential to overcome bottlenecks in wireless access through the sharing of spectrum resources. A novel access backhaul network architecture based on a Smart Gateway (Sm-GW) between the small cell base stations, e.g., LTE eNBs, and the conventional backhaul gateways, e.g., LTE Servicing/Packet Gateways (S/P-GWs) has been introduced to address the bottleneck. The Sm-GW flexibly schedules uplink transmissions for the eNBs. Based on software defined networking (SDN) a management mechanism that allows multiple operator to flexibly inter-operate via multiple Sm-GWs with a multitude of small cells has been proposed. This dissertation also comprehensively survey the studies that examine the SDN paradigm in optical networks. Along with the PHY functional split improvements, the performance of Distributed Converged Cable Access Platform (DCCAP) in the cable architectures especially for the Remote-PHY and Remote-MACPHY nodes has been evaluated. In the PHY functional split, in addition to the re-use of infrastructure with a common FFT module for multiple technologies, a novel cross functional split interaction to cache the repetitive QAM symbols across time at the remote node to reduce the transmission rate requirement of the fronthaul link has been proposed.Dissertation/ThesisDoctoral Dissertation Electrical Engineering 201

    5G Outlook – Innovations and Applications

    Get PDF
    5G Outlook - Innovations and Applications is a collection of the recent research and development in the area of the Fifth Generation Mobile Technology (5G), the future of wireless communications. Plenty of novel ideas and knowledge of the 5G are presented in this book as well as divers applications from health science to business modeling. The authors of different chapters contributed from various countries and organizations. The chapters have also been presented at the 5th IEEE 5G Summit held in Aalborg on July 1, 2016. The book starts with a comprehensive introduction on 5G and its need and requirement. Then millimeter waves as a promising spectrum to 5G technology is discussed. The book continues with the novel and inspiring ideas for the future wireless communication usage and network. Further, some technical issues in signal processing and network design for 5G are presented. Finally, the book ends up with different applications of 5G in distinct areas. Topics widely covered in this book are: • 5G technology from past to present to the future• Millimeter- waves and their characteristics• Signal processing and network design issues for 5G• Applications, business modeling and several novel ideas for the future of 5
    corecore