Recent advances in wireless communication technologies have had a transforma- tive impact on society and have directly contributed to several economic and social aspects of daily life. Increasingly, the untethered exchange of information between devices is becoming a prime requirement for further progress, which is placing an ever greater demand on wireless bandwidth. The ultra wideband (UWB) system marks a major milestone in this progress. Since 2002, when the FCC allowed the unlicensed use of low-power, UWB radio signals in the 3.1–10.6GHz frequency band, there has been significant synergistic advance in this technology at the cir- cuits, architectural and communication systems levels. This technology allows for devices to communicate wirelessly, while coexisting with other users by ensuring that its power density is sufficiently low so that it is perceived as noise to other users.
上传时间： 2020-06-01
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Once upon a time, cellular wireless networks provided two basic services: voice telephony and low-rate text messaging. Users in the network were separated by orthogonal multiple access schemes, and cells by generous frequency reuse patterns [1]. Since then, the proliferation of wireless services, fierce competition, andthe emergenceof new service classes such as wireless data and multimediahave resulted in an ever increasing pressure on network operators to use resources in a moreefficient manner.In the contextof wireless networks,two of the most common resources are power and spectrum—and, due to regulations, these resources are typically scarce. Hence, in contrast to wired networks, overprovisioning is not feasible in wireless networks.
标签： Maximization Nonconvex Wireless Utility Systems in
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Visible light communications (VLC) is the name given to an optical wireless communication system that carries information by modulating light in the visible spectrum (400–700 nm) that is principally used for illumination [1–3]. The communications signal is encoded on top of the illumination light. Interest in VLC has grown rapidly with the growth of high power light emitting diodes (LEDs) in the visible spectrum. The motivation to use the illumination light for communication is to save energy by exploiting the illumination to carry information and, at the same time, to use technology that is “green” in comparison to radio frequency (RF) technology, while using the existing infrastructure of the lighting system.
标签： Communication Visible Light
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This book is concerned with integrated circuits and systems for wireless and mobile communications. Circuit techniques and implementation of reconfigurable low-voltage and low-power single-chip CMOS transceivers for multiband and multi- mode universal wireless communications are the focus of the book. Applications encompass both long-range mobile cellular communications (GSM and UMTS) and short-range wireless LANs (IEEE802.11 and Bluetooth). Recent advances in research into transceiver architecture, RF frontend, analogue baseband, RF CAD and automatic testing are reported.
标签： Communication Wireless Circuits Systems and
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Digital radios have undergone an astonishing evolution in the last century. Born as a set of simple and power-hungry electrical and electromechanical devices for low data rate transmission of telegraph data in the Marconi age, they have transformed, thanks to substantial advances in electronic technology, into a set of small, reliable and sophisticated integrated devices supporting broadband multimedia communications. This, however, would not have been possible unless significant progress had been made in recent decades in the field of signal processing algorithms for baseband and passband signals. In fact, the core of any modern digital radio consists of a set of algorithms running over programmable electronic hardware. This book stems from the research and teaching activities of its co-authors in the field of algorithmic techniques for wireless communications. A huge body of technical literature has accumulated in the last four decades in this area, and an extensive coverage of all its important aspects in a single textbook is impossible. For this reason, we have selected a few important topics and, for ease of reading, organized them into two parts.
标签： Communications Algorithmic Techniques Wireless
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For more than three decades, Micro Electro Mechanical Systems (MEMS) have steadily transitioned out of research labs and into production forming a more than $10 billion market [1]. MEMS devices such as accelerometers, pressure sensors and microphones, to name a few, have seen immense utilization, particularly in the consumer electronics market, because of their compact sizes and minute power consumptions. In addition, these devices benefit from batch fabrication, which has enabled year-over-year reductions in cost [2]. In recent years,
上传时间： 2020-06-06
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District energy (DE) systems use central heating and/or cooling facilities to provide heating and/or cooling services for communities. The advantages of district energy over conventional heating and cooling include improved efficiency, reliability and safety, reduced environmental impact, and for many situations better economics. DE systems can be particularly beneficial when integrated with cogeneration plants for electricity and heat, i.e., with combined heat and power (CHP) plants. One of the main impediments to increased use of cogeneration-based district energy is a lack of understanding of the behavior of integrated forms of such systems. This book is aimed at providing information on district energy and cogeneration tech- nologies, as well as systems that combine them.
标签： Cogeneration District Systems Energy and
上传时间： 2020-06-07
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n its Framework and Roadmap for Smart Grid Interoperability Standards, the US National Institute of Standards and Technology declares that a twenty-first-century clean energy economy demands a twenty-first-century electric grid. 1 The start of the twenty-first century marked the acceleration of the Smart Grid evolution. The goals of this evolution are broad, including the promotion of widespread and distributed deployment of renewable energy sources, increased energy efficiency, peak power reduction, automated demand response, improved reliability, lower energy delivery costs, and consumer participation in energy management.
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The large-scale deployment of the smart grid (SG) paradigm could play a strategic role in supporting the evolution of conventional electrical grids toward active, flexible and self- healing web energy networks composed of distributed and cooperative energy resources. From a conceptual point of view, the SG is the convergence of information and operational technologies applied to the electric grid, providing sustainable options to customers and improved security. Advances in research on SGs could increase the efficiency of modern electrical power systems by: (i) supporting the massive penetration of small-scale distributed and dispersed generators; (ii) facilitating the integration of pervasive synchronized metering systems; (iii) improving the interaction and cooperation between the network components; and (iv) allowing the wider deployment of self-healing and proactive control/protection paradigms.
标签： Computational Intelligence
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Electricity has been chosen as the most convenient and useful form of energy, due to its ease of transportation over large distances and easy conversion to other energy forms. The biggest inconvenience with electricity is that it cannot be stored and must be utilized at the moment of generation. The storage of a large amount of electrical energy is usually connected with its conversion to other types of energy, which significantly reduces the efficiency of such processes. The aim of the power system, often treated as the biggest and the most complex machine ever built, is to deliver uninterruptible electric energy of demanded quality parameters to consumers.
标签： Electromagnetic Interference Conducted
上传时间： 2020-06-07
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