The growth of mobile technologies is remarkable. At a recent Mobile World Congress Conference, Eric Schmidt, CEO of Google predicted that within three years, smart phones will surpass Personal Com- puter sales. The number of mobile phones used worldwide has exceeded 4.6 billion with continued growth expected in the future. In fact, in the United States alone, the numbers of mobile phone users comprise over 80% of the population.
标签： Opportunities Consumption Technology Mobile
上传时间： 2020-05-30
上传用户：shancjb
The insinuation of telecommunications into the daily fabric of our lives has been arguably the most important and surprising development of the last 25 years. Before this revolution, telephone service and its place in our lives had been largely stable for more than a generation. The growth was, so to speak, lateral, as the global reach of telecommunications extended and more people got telephone service. The distinction between oversea and domestic calls blurred with the advances in switching and transmission, undersea cable, and communication satellites. Traffic on the network remained overwhelmingly voice, largely in analog format with facsimile (Fax) beginning to make inroads.
标签： Telecommunications Modeling Analysis and of
上传时间： 2020-05-31
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In case you haven’t noticed, multimedia communication over IP and wireless net- works is exploding. Applications such as BitTorrent, used primarily for video downloads, now take up the lion’s share of all traffic on the Internet. Music file sharing, once on the legal cutting edge of massive copyright infringement on col- lege campuses around the world, has moved into the mainstream with signifi- cant legal downloads of music and video to devices such as the iPod and nu- merous other portable media players.
标签： Multimedia Over IP
上传时间： 2020-05-31
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Wireless communication is witnessing tremendous growth with great proliferation of different standards covering wide ,local and personal area networks
标签： Multi-Standard Receivers Wireless CMOS
上传时间： 2020-05-31
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Rapid growth of wireless communication services in recent decades has created a huge demand of radio spectrum. Spectrum scarcity and utilization inefficiency limit the development of wireless networks. Cognitive radio is a promising tech- nology that allows secondary users to reuse the underutilized licensed spectrum of primary users. The major challenge for spectrum sharing is to achieve high spectrum efficiency while making non-intrusive access to the licensed bands. This requires in- formation of availability and quality of channel resources at secondary transmitters, however, is difficult to be obtained perfectly in practice.
标签： Opportunistic Spectrum Sharing
上传时间： 2020-05-31
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This book provides the essential design techniques for radio systems that operate at frequencies of 3 MHz to 100 GHz and which will be employed in the telecommunication service. We may also call these wireless systems, wireless being synonymous with radio, Telecommunications is a vibrant indus- try, particularly on the ‘‘radio side of the house.’’ The major supporter of this upsurge in radio has been the IEEE and its 802 committees. We now devote Ž . an entire chapter to wireless LANs WLANs detailed in IEEE 802.11. We also now have subsections on IEEE 802.15, 802.16, 802.20 and the wireless Ž . Ž metropolitan area network WMAN . WiFi, WiMax,, and UWB ultra wide- . band are described where these comparatively new radio specialties are demonstrating spectacular growth.
标签： Telecommunication Design System Radio for
上传时间： 2020-06-01
上传用户：shancjb
Radio frequency spectrum is a scarce and critical natural resource that is utilized for many services including surveillance, navigation, communication, and broadcast- ing. Recent years have seen tremendous growth in the use of spectrum especially by commercial cellular operators. Ubiquitous use of smartphones and tablets is one of the reasons behind an all-time high utilization of spectrum. As a result, cellular operators are experiencing a shortage of radio spectrum to meet bandwidth demands of users. On the other hand, spectrum measurements have shown that much spectrum not held by cellular operators is underutilized even in dense urban areas. This has motivated shared access to spectrum by secondary systems with no or minimal impact on incumbent systems. Spectrum sharing is a promising approach to solve the problem of spectrum congestion as it allows cellular operators access to more spectrum in order to satisfy the ever-growing bandwidth demands of commercial users.
标签： Spectrum Sharing Between Radars
上传时间： 2020-06-01
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The continuing explosive growth in mobile communication is demanding more spectrally efficient radio access technologies than the prevalent second generation (2G) systems such as GSM to handle just the voice traffic. We are already witnessing high levels of mobile penetration exceeding 70% in some countries. It is anticipated that by 2010 more than half of all communications will be carried out by mobile cellular networks. On the other hand, the information revolution and changing life habits are bringing the requirement of commu- nicating on a multimedia level to the mobile environment. But the data handling capabilities and flexibility of the 2G cellular systems are limited.
上传时间： 2020-06-01
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The information age is exploding around us, giving us access to dizzying amounts of data the instant it becomes available. Smart phones and tablets provide an untethered experience that offers stream- ing video, audio, and other media formats to just about any place on the planet. Even people who are not “computer literate” use Facebook to catch up with friends and family, use Google to research a new restaurant choice and print directions to get there, or Tweet their reactions once they have sampled the fare. The budding Internet-of-things will only catalyze this data eruption. The infrastructure supporting these services is also growing exponentially, and the technology that facilitates this rapid growth is virtualization.
上传时间： 2020-06-01
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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
上传时间： 2020-06-01
上传用户：shancjb
