Cognitive radio has emerged as a promising technology for maximizing the utiliza- tion of the limited radio bandwidth while accommodating the increasing amount of services and applications in wireless networks. A cognitive radio (CR) transceiver is able to adapt to the dynamic radio environment and the network parameters to maximize the utilization of the limited radio resources while providing flexibility in wireless access. The key features of a CR transceiver are awareness of the radio envi- ronment (in terms of spectrum usage, power spectral density of transmitted/received signals, wireless protocol signaling) and intelligence.
標簽： Cognitive Wireless Network
上傳時間： 2020-05-26
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Mobile communication has gained significant importance in today’s society. As of 2010, the number of mobile phone subscribers has surpassed 5 billion [ABI10], and the global annual mobile revenue is soon expected to top $1 trillion [Inf10]. While these numbers appear promising for mobile operators at first sight, the major game-changer that has come up recently is the fact that the market is more and more driven by the demand for mobile data traffic [Cis10].
上傳時間： 2020-05-27
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While teaching classes on digital transmission and mobile communications for undergraduate and graduate students, I was wondering if it would be possible to write a book capable of giving them some insight about the practical meaning of the concepts, beyond the mathematics; the same insight that experience and repetitive contact with the subject are capable to construct; the insight that is capable of build- ing the bridge between the theory and how the theory manifests itself in practice.
標簽： Transmission Digital
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Fundamentals of WiMAX was consciously written to appeal to a broad audience, and to be of value to anyone who is interested in the IEEE 802.16e standards or wireless broadband networks more generally. The book contains cutting-edge tutorials on the technical and theoretical under- pinnings to WiMAX that are not available anywhere else, while also providing high-level over- views that will be informative to the casual reader.
標簽： Understanding Fundamentals WiMAX of
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The writing of this book was prompted by two main developments in wireless communications in the past decade. First is the huge surge of research activities in physical-layer wireless communication theory. While this has been a subject of study since the 60’s, recent developments in the field, such as opportunistic and multi-input multi-output (MIMO) communication techniques, have brought completely new per- spectives on how to communicate over wireless channels.
標簽： Communication Fundamentals Wireless of
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Providing QoS while optimizing the LTE network in a cost efficient manner is very challenging. Thus, radio scheduling is one of the most important functions in mobile broadband networks. The design of a mobile network radio scheduler holds several objectives that need to be satisfied, for example: the scheduler needs to maximize the radio performance by efficiently distributing the limited radio re- sources, since the operator’s revenue depends on it.
標簽： Communications Future Mobile LTE
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This book is intended to help electric power and telephone company personnel and individuals interested in properly protecting critical tele- communications circuits and equipment located in high voltage (HV) environments and to improve service reliability while maintaining safe working conditions. Critical telecommunications circuits are often located in HV environments such as electric utility power plants, substations, cell sites on power towers, and standalone telecommuni- cations facilities such as 911 call centers and mountaintop telecom- munications sites.
標簽： Protection Voltage High
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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.
標簽： HSDPAHSUPA Access Speed Radio UMTS High for
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There are few technologies that have had a more profound effect on people’s lives than mobile communications. As recently as twenty years ago no one had a mobile phone, while today 1.4 billion men, women and children depend on them. This now exceeds the number of landline users, where it took the preceding one hundred years to reach the 1 billion mark. The ability to make mobile voice calls turns out to be the answer to a deeply felt need across different cultures who simply want to communicate.
標簽： Communications Wireless Mobile and
上傳時間： 2020-05-30
上傳用戶：shancjb
With this book at your fingertips, you, the reader, and I have something in common. We share the same interest in mobile radio channels. This area attracted my interest first in autumn 1992 whenImovedfromindustrytoacademiatofindachallengeinmylifeandtopursueascientific career. Since then, I consider myself as a student of the mobile radio channel who lives for modelling, analyzing, and simulating them. While the first edition of this book resulted from my teaching and research activities at the Technical University of Hamburg-Harburg (TUHH), Germany, the present second edition is entirely an outcome of my work at the University of Agder, Norway.
上傳時間： 2020-05-30
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