Optical communication technology has been extensively developed over the last 50 YEARS, since the proposed idea by Kao and Hockham [1]. However, only during the last 15 YEARS have the concepts of communication foundation, that is, the modulation and demodulation techniques, been applied. This is pos- sible due to processing signals using real and imaginary components in the baseband in the digital domain. The baseband signals can be recovered from the optical passband region using polarization and phase diversity tech- niques, as well as technology that was developed in the mid-1980s.
标签: Transmission Processing Digital Optical
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The continued reduction of integrated circuit feature sizes and commensurate improvements in device performance are fueling the progress to higher functionality and new application areas. For example, over the last 15 YEARS, the performance of microprocessors has increased 1000 times. Analog circuit performance has also improved, albeit at a slower pace. For example, over the same period the speed/resolution figure-of-merit of analog-to-digital converters improved by only a factor 10.
标签: Digitally Assisted Pipeline ADCs
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The rapid growth in mobile communications has led to an increasing demand for wide- band high data rate communications services. In recent YEARS, Distributed Antenna Systems (DAS) has emerged as a promising candidate for future (beyond 3G or 4G) mobile communications, as illustrated by projects such as FRAMES and FuTURE. The architecture of DAS inherits and develops the concepts of pico- or micro-cell systems, where multiple distributed antennas or access points (AP) are connected to and con- trolled by a central unit.
标签: Distributed Antenna Systems
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Wireless Fidelity (Wi-Fi) networks have become mainstream over the last few YEARS. What started out as cable replacement for static desktops in indoor networks has been extended to fully mobile broadband applications involving moving vehicles, high-speed trains, and even airplanes.
标签: Technologies Emerging Wireless Theory LANs in
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The telecommunications industry is undoubtedly in a period of radical change with the advent of mobile broadband radio access and the rapid convergence of Internet and mobile services. Some of these changes have been enabled by a fundamental shift in the underlying technologies; mobile networks are now increasingly based on a pure Internet Protocol (IP) network architecture. Since the first edition of this book was published in 2009, a multitude of connected devices from eBook readers to smartphones and even Machine-to-Machine (M2M) technologies have all started to benefit from mobile broadband. The sea change over the last few YEARS is only the beginning of a wave of new services that will fundamentally change our economy, our society, and even our environment. The evolution towards mobile broadband is one of the core underlying parts of this revolution and is the focus of this book.
标签: Networks Packet EPC and 4G
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Over the past ten YEARS there has been a revolution in the devel- opment and acceptance of mobile products. In that period, cel- lular telephony and consumer electronics have moved from the realm of science fiction to everyday reality. Much of that revolu- tion is unremarkable – we use wireless, in its broadest sense, for TV remote controls, car keyfobs, travel tickets and credit card transactions every day. At the same time, we have increased the number of mobile devices that we carry around with us. However, in many cases the design and function of these and other static products are still constrained by the wired connections that they use to transfer and share data.
标签: Short-Range Essentials Wireless of
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Throughout the course of my work in multihop mobile ad hoc networks (MANET) over the last several YEARS, I reached the conclusion that mobility models and perfor- mance metrics need to be treated in detail in designing these networks that are the ultimatefrontierinwirelesscommunications. Awidevarietyofmobilitymodelscan be used by mobile nodes.
标签: Handbook Networks Mobility Mobile Models Hoc for Ad of
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The first Third Generation Partnership Project (3GPP) Wideband Code Division Multiple Access (WCDMA) networks were launched during 2002. By the end of 2005 there were 100 open WCDMA networks and a total of over 150 operators having frequency licenses for WCDMA operation. Currently, the WCDMA networks are deployedinUniversalMobileTelecommunicationsSystem(UMTS)bandaround2GHz in Europe and Asia including Japan and Korea. WCDMA in America is deployed in the existing 850 and 1900 spectrum allocations while the new 3G band at 1700/2100 is expected to be available in the near future. 3GPP has defined the WCDMA operation also for several additional bands, which are expected to be taken into use during the coming YEARS.
标签: HSDPAHSUPA Access Speed Radio UMTS High for
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The genesis for this book was my involvement with the development of the SystemView (now SystemVue) simulation program at Elanix, Inc. Over several YEARS of development, technical support, and seminars, several issues kept recur- ring. One common question was, “How do you simulate (such and such)?” The sec- ond set of issues was based on modern communication systems, and why particular developers did what they did. This book is an attempt to gather these issues into a single comprehensive source.
标签: Communication Introduction Systems to
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To meet the future demand for huge traffic volume of wireless data service, the research on the fifth generation (5G) mobile communication systems has been undertaken in recent YEARS. It is expected that the spectral and energy efficiencies in 5G mobile communication systems should be ten-fold higher than the ones in the fourth generation (4G) mobile communication systems. Therefore, it is important to further exploit the potential of spatial multiplexing of multiple antennas. In the last twenty YEARS, multiple-input multiple-output (MIMO) antenna techniques have been considered as the key techniques to increase the capacity of wireless communication systems. When a large-scale antenna array (which is also called massive MIMO) is equipped in a base-station, or a large number of distributed antennas (which is also called large-scale distributed MIMO) are deployed, the spectral and energy efficiencies can be further improved by using spatial domain multiple access. This paper provides an overview of massive MIMO and large-scale distributed MIMO systems, including spectral efficiency analysis, channel state information (CSI) acquisition, wireless transmission technology, and resource allocation.
标签: Large-scale Antenna Systems
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