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2020

  • Enhanced+Radio+Access+Technologies

    Following chapter introduces the mobile communication, gives a short history of wireless communication evolution, and highlights some application scenarios predestined for the use of mobile devices. Cellular and wireless based systems related to different generations of mobile communication, including GSM, IS-95, PHS, AMPS, D-AMPS, cdma2000 and WCDMA are also described by this Chapter. Much attention in this chapter is given to express the wireless based networks, such as Wi-Fi and WiBro/WiMax, and wireless broadcasting systems, including DMB, DVB-H, and ISDB-T. We conclude the chapter with the future vision of mobile communication evolution

    标签: Technologies Enhanced Access Radio

    上传时间: 2020-05-27

    上传用户:shancjb

  • EPC and 4G Packet Networks

    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

    上传时间: 2020-05-27

    上传用户:shancjb

  • Essentials+of+LTE+and+LTE-A

    The next-generation wireless broadband technology is changing the way we work, live, learn, and communicate through effective use of state- of-the-art mobile broadband technology. The packet-data-based revolu- tion started around 2000 with the introduction of 1x Evolved Data Only (1xEV-DO) and 1x Evolved Data Voice (1xEV-DV) in 3GPP2 and High Speed Downlink Packet Access (HSDPA) in 3GPP. The wireless broad- band fourth-generation technology (4G) is an evolution of the packet- based 3G system and provides a comprehensive evolution of the Universal Mobile Telecommunications System specifications so as to remain competitive with other broadband systems such as 802.16e (WiMAX)

    标签: Essentials LTE-A LTE and of

    上传时间: 2020-05-27

    上传用户:shancjb

  • Essentials+of+Radio+Wave+Propagation

    The objective of this book is to allow the reader to predict the received signal power produced by a particular radio transmitter. The first two chapters examine propagation in free space for point-to-point and point-to-area transmission, respectively. This is combined with a dis- cussion regarding the characteristics of antennas for various purposes. In chapter 3, the effect of obstacles, whether buildings or mountains, is discussed and analytical methods, whereby the strength of a signal is the shadow of an obstacle can be predicted, are presented. 

    标签: Propagation Essentials Radio Wave of

    上传时间: 2020-05-27

    上传用户:shancjb

  • Essentials+of+Short-Range+Wireless

    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

    上传时间: 2020-05-27

    上传用户:shancjb

  • Essentials+of+Wireless+Mesh+Networking

    Wirelessmeshnetworkingisahotandgrowingtopic,stillinitsinfancyin some ways, whilst already shown to be capable in others. From a military beginning, mesh networks moved to civilian use and are now being deployed worldwide as both local area networks (LANs) and metro- politan area networks (MANs). However, these deployments are still ‘leading edge’ and it is not yet clear what the most enduring applications of mesh will be – particularly as the market moves from early adopters towards widespread take up.

    标签: Essentials Networking Wireless Mesh of

    上传时间: 2020-05-27

    上传用户:shancjb

  • Fading+and+Shadowing+in+Wireless+Systems

    During the past two decades there has been a substantial growth in research in wireless communications. The number of journals published from various parts of the world catering to the research community has grown exponentially. Despite such a growth, the engineering community still needs more information so as to thoroughly comprehend wireless channel characteristics. What specifically must be understood are the effects of channel degradation brought on by statistical fluctua- tions in the channel. 

    标签: Shadowing Wireless Systems Fading and in

    上传时间: 2020-05-27

    上传用户:shancjb

  • Feedback+Strategies+for+Wireless+Communication

    During the past decade, many wireless communication techniques have been developedto achievevariousgoals suchas higherdata rate,morerobustlink quality, and higher number of users in a given bandwidth. For wireless communication systems, depending on the availability of a feedback link, two approaches can be considered: namely open and closed loop. Open loop communication system that does not exploit the channel knowledge at the transmitter is now well understood from both a theoretical and practical point of view. 

    标签: Communication Strategies Feedback Wireless for

    上传时间: 2020-05-27

    上传用户:shancjb

  • Femtocells+Technologies+and+Deployment

    In cellular networks, it is estimated that 2 3 of calls and over 90% of data services occur indoors. However, some surveys show that many households and businesses experience a poor indoor coverage problem. It has been identified that poor coverage is the main reason for churn, which is very costly for operators in saturated markets. How to provide good indoor coverage cost effectively is thus a demanding challenge for operators.

    标签: Technologies Femtocells Deployment and

    上传时间: 2020-05-27

    上传用户:shancjb

  • Free+Space+Optical+Communication+System

    Free Space Optical Communication (FSOC) is an effective alternative technology to meet the Next Generation Network (NGN) demands as well as highly secured (mili- tary) communications. FSOC includes various advantages like last mile access, easy installation, free of Electro Magnetic Interference (EMI)/Electro Magnetic Compatibil- ity (EMC) and license free access etc. In FSOC, the optical beam propagation in the turbulentatmosphereisseverelyaffectedbyvariousfactorssuspendedinthechannel, geographicallocationoftheinstallationsite,terraintypeandmeteorologicalchanges. Therefore a rigorous experimental study over a longer period becomes significant to analyze the quality and reliability of the FSOC channel and the maximum data rate that the system can operate since data transmission is completely season dependent.

    标签: Communication Optical System Space Free

    上传时间: 2020-05-27

    上传用户:shancjb