474 research outputs found

    Cooperative Radio Communications for Green Smart Environments

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    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

    Antenna Designs Aiming at the Next Generation of Wireless Communication

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    Millimeter-wave (mm-wave) frequencies have drawn large attention, specically for the fifth generation (5G) of wireless communication, due to their capability to provide high data-rates. However, design and characterization of the antenna system in wireless communication will face new challenges when we move up to higher frequency bands. The small size of the components at higher frequencies will make the integration of the antennas in the system almost inevitable. Therefore, the individual characterization of the antenna can become more challenging compared to the previous generations.This emphasizes the importance of having a reliable, simple and yet meaningful Over-the-Air (OTA) characterization method for the antenna systems. To avoid the complexity of using a variety of propagation environments in the OTA performance characterization, two extreme or edge scenarios for the propagation channels are presented, i.e., the Rich Isotropic Multipath (RIMP) and Random Line-of-Sight (Random-LoS). MIMO efficiency has been defined as a Figure of Merit (FoM), based on the Cumulative Distribution Function (CDF) of the received signal, due to the statistical behavior of the signal in both RIMP and Random-LoS. Considering this approach, we have improved the design of a wideband antenna for wireless application based on MIMO efficiency as the FoM of the OTA characterization in a Random-LoS propagation environment. We have shown that the power imbalance and the polarization orthogonality plays major roles determining the 2-bitstream MIMO performance of the antenna in Random-LoS. In addition, a wideband dual-polarized linear array is designed for an OTA Random-LoS measurement set-up for automotive wireless systems. The next generation of wireless communications is extended throughout multiple narrow frequency bands, varying within 20-70 GHz. Providing an individual antenna system for each of these bands may not be feasible in terms of cost, complexity and available physical space. Therefore, Ultra-Wideband (UWB) antenna arrays, coveringmultiple mm-wave frequency bands represent a versatile candidate for these antenna systems. In addition to having wideband characteristics, these antennas should offer an easy integration capability with the active modules. We present a new design of UWB planar arrays for mm-wave applications. The novelty is to propose planar antenna layouts to provide large bandwidth at mm-wave frequencies, using simplified standard PCB manufacturing techniques. The proposed antennas are based on Tightly Coupled Dipole Arrays (TCDAs) concept with integrated feeding network

    The self-organizing radio networks and ultra wide band signals

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    The paper proposes to use impulse radio ultra wide band signals in self-organizing ad hoc and MANET networks to solve multiple access and widen networks coverage area problems. New methods of signals reception and information capacity increasing are proposed

    Radio Communications

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    In the last decades the restless evolution of information and communication technologies (ICT) brought to a deep transformation of our habits. The growth of the Internet and the advances in hardware and software implementations modified our way to communicate and to share information. In this book, an overview of the major issues faced today by researchers in the field of radio communications is given through 35 high quality chapters written by specialists working in universities and research centers all over the world. Various aspects will be deeply discussed: channel modeling, beamforming, multiple antennas, cooperative networks, opportunistic scheduling, advanced admission control, handover management, systems performance assessment, routing issues in mobility conditions, localization, web security. Advanced techniques for the radio resource management will be discussed both in single and multiple radio technologies; either in infrastructure, mesh or ad hoc networks

    Femtocell deployment; next generation in cellular systems

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    The final Bachelor’s Thesis that is shown below has such a final purpose of giving an overview of the inclusion of the so-called Femtocells (or Home Node B) in the current cellular systems. The main objective is to give a clear but simple idea about the concepts of Femtocells, as well as to explain the benefits and disadvantages of the mass uses of these services both for consumers and associated companies with this phenomenon. In this text it is also possible to find a brief review of wireless technologies throughout the history of telecommunications, as well as an introduction to the more current wireless technologies, with a special interest in the concept of cellular systems. In the last chapter a simple mathematical explanation of the key issue of interference between Femtocells and macrocellular networks is presented, with a brief argument about possible solutions

    A Survey of Air-to-Ground Propagation Channel Modeling for Unmanned Aerial Vehicles

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    In recent years, there has been a dramatic increase in the use of unmanned aerial vehicles (UAVs), particularly for small UAVs, due to their affordable prices, ease of availability, and ease of operability. Existing and future applications of UAVs include remote surveillance and monitoring, relief operations, package delivery, and communication backhaul infrastructure. Additionally, UAVs are envisioned as an important component of 5G wireless technology and beyond. The unique application scenarios for UAVs necessitate accurate air-to-ground (AG) propagation channel models for designing and evaluating UAV communication links for control/non-payload as well as payload data transmissions. These AG propagation models have not been investigated in detail when compared to terrestrial propagation models. In this paper, a comprehensive survey is provided on available AG channel measurement campaigns, large and small scale fading channel models, their limitations, and future research directions for UAV communication scenarios

    Converged wireline and wireless signal distribution in optical fiber access networks

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