The General Packet Radio Service (GPRS) allows an end user to send and receive data in packet transfer mode within a public land mobile network (PLMN) without using a permanent connection between the mobile station (MS) and the external network during data transfer. This way, GPRS opti- mizes the use of network and radio resources (RRs) since, unlike circuit- switched mode, no connection between the MS and the external network is established when there is no data flow in progress. Thus, this RR optimiza- tion makes it possible for the operator to offer more attractive fees.
上传时间: 2020-05-27
上传用户:shancjb
Your Cisco Networking Academy Course Booklet is designed as a study resource you can easily read, high- light, and review on the go, wherever the Internet is not available or practical: ■ The text is extracted directly, word-for-word, from the online course so you can highlight important points and take notes in the “Your Chapter Notes” section. ■ Headings with the exact page correlations provide a quick reference to the online course for your class- room discussions and exam preparation. ■ An icon system directs you to the online curriculum to take full advantage of the images, labs, Packet Tracer activities, and dynamic Flash-based activities embedded within the Networking Academy online course interface.
标签: Switching Wireless LAN and
上传时间: 2020-05-27
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This books presents the research work of COST 273 Towards Mobile Broadband Multimedia Networks, hence, it reports on the work performed and on the results achieved within the project by its participants. The material presented here corresponds to the results obtained in four years of collaborative work by more than 350 researchers from 137 institutions (universities, operators, manufacturers, regulators, independent laboratories and others – a full list is provided in Appendix B) belonging to 29 countries (mainly European, but also from Asia and North America) in the area of mobileradio. Theobjectiveofpublishingtheseresultsasabookisessentiallytomakethemavailable to an audience wider than the project. In fact, it just follows a ‘tradition’ of previous COST Actions in this area of telecommunications, i.e. COST 207, 231 and 259.
标签: Multimedia Techniques Broadband Networks Mobile
上传时间: 2020-05-30
上传用户:shancjb
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 telecommunications industry has seen a rapid boost within the last decade. New realities and visions of functionalities in various telecommunications networks have brought forward the concept of next-generation networks (NGNs). The competitions among operators for support- ing various services, lowering of the cost of having mobile and cellular phones and smartphones, increasing demand for general mobility, explosion of digital traffic, and advent of convergence network technologies added more dynamism in the idea of NGNs. In fact, facilitating con- vergence of networks and convergence of various types of services is a significant objective of NGNs.
标签: Next-Generation Converged Networks
上传时间: 2020-05-31
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The outcome of the 3GPP SAE (system architecture evolution) technical study and specification work is a set of standards that specifies the evolution of the packet core network for GSM/GPRS and WCDMA/HSPA to an all-IP architec- ture and enables a feature-rich ‘common packet core’ for radio accesses devel- oped within 3GPP and also by other standardization fora.
标签: Evolved Packet Core SAE and the
上传时间: 2020-06-01
上传用户:shancjb
Spread-spectrum communication is a core area within the field of digital communication. Originally used in military networks as countermeasures against the threats of jamming and interception, spread-spectrum systems are now widely used in commercial applications and are part of several wireless and mobile communication standards. Although spread-spectrum communication is a staple topic in textbooks on digital communication, its treatment is usually cursory. This book is designed to provide a more intensive examination of the subject that is suitable for graduate students and practicing engineers with a solid background in the theory of digital communication. As the title indicates, this book stresses principles rather than specific current or planned systems, which are described in manyotherbooks.My goal in this bookis to providea concisebut lucidexplanation of the fundamentals of spread-spectrum systems with an emphasis on theoretical principles.
标签: Spread-Spectrum Communication Systems 2nd
上传时间: 2020-06-01
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Regulation is a pervasive feature of the telecommunications services industry today. Government-appointed regulators and judicial or quasi-judicial bodies oversee it in countries at all stages of economic development. Its primary purpose is to encourage, nourish and maintain competition in national and international telecommunications services markets. It is, therefore, a fundamental feature of the legal and commercial landscape within which network owners and service providers operate. The modern development of regulation may be traced to the liberalisation of the industry from national monopolies from the 1980s onwards.
标签: Telecommunications Regulation
上传时间: 2020-06-01
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The digital dilemma: Telecoms fi rms prepare for the future is an Economist Intelligence Unit (EIU) report commissioned by WIPRO. The report strives to identify the key issues that companies within the telecoms sector are facing as they attempt to reshape their businesses to compete in a more digitised world.
上传时间: 2020-06-01
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Wireless communications has become a field of enormous scientific and economic interest. Recent success stories include 2G and 3G cellular voice and data services (e.g., GSM and UMTS), wireless local area networks (WiFi/IEEE 802.11x), wireless broadband access (WiMAX/IEEE 802.16x), and digital broadcast systems (DVB, DAB, DRM). On the physical layer side, traditional designs typically assume that the radio channel remains constant for the duration of a data block. However, researchers and system designers are increasingly shifting their attention to channels that may vary within a block. In addition to time dispersion caused by multipath propagation, these rapidly time-varying channels feature frequency dispersion resulting from the Doppler effect. They are, thus, often referred to as being “doubly dispersive.”
标签: Time-Varying Channels
上传时间: 2020-06-01
上传用户:shancjb