Many wireless communications channels consist of multiple signal paths from the transmitter to receiver. This multiplicity of paths leads to a phenomenon known as multipath fading. The multiple paths are caused by the presence of objects in the physical environment that, through the mechanisms of propagation, alter the path of radiated energy. These objects are referred to as scatterers. In the past, researchers often looked at ways to mitigate multipath scattering, such as in diversity systems. Multiple-input, multiple-output (MIMO) systems, on the other hand, use multipath diversity to their advantage; a MIMO system has the ability to translate increased spatial diversity into increased channel capacity.
标签： Multiple-Output Multiple-Input Channel Models
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The family of recent wireless standards included the optional employment of MIMO tyechniques. This was motivated by the observation according to the classic Shannon-Hartley law the achiev- able channel capacity increases logarithmically with the transmit power. By contrast, the MIMO capacity increases linearly with the number of transmit antennas, provided that the number of receive antennas is equal to the number of transmit antennas.
标签： Multi-Functional Near-Capacity Systems MIMO
上传时间： 2020-05-31
上传用户：shancjb
The family of recent wireless standards included the optional employment of MIMO tyechniques. This was motivated by the observation according to the classic Shannon-Hartley law the achiev- able channel capacity increases logarithmically with the transmit power. By contrast, the MIMO capacity increases linearly with the number of transmit antennas, provided that the number of receive antennas is equal to the number of transmit antennas.
标签： Simulation Modeling Network and
上传时间： 2020-05-31
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Coverage of routing techniques in various wired and wireless networks is the unique proposition of this book. Routing protocols and algorithms are the brains of any network. The selection of topics in this book is clear: we attempt to explain routing in its entirety, starting from fundamental concepts, then moving through routing on the Internet, and finally cutting across the recent‐day cellular, ad hoc, and wireless networks.
标签： Fundamentals Applications Network Routing
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Informationnetworkinghasemergedasamultidisciplinarydiversifiedareaofresearchover thepastfewdecades.Fromtraditionalwiredtelephonytocellularvoicetelephonyandfrom wired access to wireless access to the Internet, information networks have profoundly impactedourlifestyle.Atthetimeofwriting,over3billionpeoplearesubscribedtocellular services and close to a billion residences have Internet connections.
上传时间： 2020-05-31
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European Research Framework programs are public policy instruments designed to strengthen European competitiveness through cooperation. Although they have a fixed time frame, determined research themes, and a specific expected impact, the achievements in research and development (R&D) made by these funded proj- ects pave the way for a research continuum.
标签： Communications Horizons Wireless Mobile New and in
上传时间： 2020-05-31
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European Research Framework Programs are a public policy instrument to strengthen European competitiveness through cooperation. Although they have a fixed timeframe, determined research themes, and specific expected impact, the achievements in research and development (R&D) made by the funded projects pave the way for a research continuum.
标签： New Horizons Mobile wireless
上传时间： 2020-05-31
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Mobile wireless communications are in constant evolution due to the continu- ously increasing requirements and expectations of both users and operators. Mass multimedia* services have been for a long time expected to generate a large amount of data traffic in future wireless networks [1]. Mass multimedia services are, by definition, purposed for many people. In general, it can be distinguished between the distribution of any popular content over a wide area and the distribu- tion of location-dependent information in highly populated areas. Representative examples include the delivery of live video streaming content (like sports compe- titions, concerts, or news) and file download (multimedia clips, digital newspa- pers, or software updates).
标签： Broadcasting Generation Mobile Next
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All wireless communication standards, existing and under development, adopt or consider adopting orthogonal frequency-division multiplexing (OFDM) as the modulation technique. It is clear that OFDM has become the definitive modulation scheme in current and future wireless communication systems.
标签： Baseband Receiver Design OFDM
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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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