Cellular communication systems

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  • This book focuses on issues related to multiple access for cellular mobile communications, with a specific interest in access arbitration through multiple access protocols situated at the lower sub-layer of the second OSI layer, namely the medium access control (MAC) layer. In this chapter, first an introduction to cellular mobile communication systems is provided.

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  • The third generation (3G) mobile communication system is the next big thing in the world of mobile telecommunications. The first generation included analog mobile phones [e.g., Total Access Communications Systems (TACS), Nordic Mobile Telephone (NMT), and Advanced Mobile Phone Service (AMPS)], and the second generation (2G) included digital mobile phones [e.g., global system for mobile communications (GSM), personal digital cellular (PDC), and digital AMPS (D-AMPS)].

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  • As stated in Chapter 1, Section 1.2, requirements for International Mobile Telecommunications-2000 (IMT-2000) include system flexibility, economy and conditions on data transmission speed defined in numerical terms. The minimum performance requirement in terms of transmission speed is 2 Mbit/s in an indoor environment, 384 kbit/s in a pedestrian mode and 144 kbit/s in a vehicle mode.

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  • The previous chapters have concentrated on the two leading second generation (2G) cellular systems: GSM and IS-95. These systems are deployed in many parts of the world and will continue to operate and evolve during the next decade as third generation (3G) systems are rolled out. We may expect that the new 3G systems will be harmonised with their evolved 2G counterparts, and that slowly 2G spectra will be refarmed to provide extra 3G spectra. No 3G systems are currently deployed, although trials are in progress. As a consequence, this chapter, which deals with systems that are about to be...

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  • Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Cross-Layer Design and Analysis of Downlink Communications in Cellular CDMA Systems

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  • The generic cellular communication system, shown in Fig.l, is an integrated network comprising a land base wire line telephone network and a composite wired-wireless network. The land base network is the traditional telephone system in which all telephone subscribers are connected to a central switching network, commonly known as PSTN (Public Switching Telephone Network). It is a digital switching system, providing: i) Switching, ii) Billing, iii) 911 dialing, iv)l-800 and 1-900 calling features, v)...

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  • GSM (Global System for Mobile Communications, originally Groupe Spécial Mobile), is a standard set developed by the European Telecommunications Standards Institute (ETSI) to describe technologies for second generation (2G) digital cellular networks. Developed as a replacement for first generation (1G) analog cellular networks, the GSM standard originally described a digital, circuit switched network optimized for full duplex voice telephony.

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  • Generation Change in Cellular Systems In Japan, mobile communications systems based on cellular technology have evolved, as illustrated in Figure 1.1. The first-generation analog car phones were first introduced in 1979, followed by the commercialization of the second-generation digital phones in 1993. Mobile phone subscribers have rapidly increased in number since then, owing to the liberation of terminal sales and continuous price reductions. In March 2000, the number of mobile phone subscribers outnumbered those of fixed telephones.

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  • Our first chapter puts LTE into its historical context, and lays out its requirements and key technical features. We begin by reviewing the architectures of UMTS and GSM, and by introducing some of the terminology that the two systems use. We then summarize the history of mobile telecommunication systems, discuss the issues that have driven the development of LTE, and show how UMTS has evolved first into LTE and then into an enhanced version known as LTE-Advanced. The chapter closes by reviewing the standardization process for LTE....

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  • Mobile communication networks were commercially launched as Circuit-Switched (CS) systems centering on speech communication services. The First-Generation (1G) analog system evolved into the Second-Generation (2G) digital system, followed by the introduction of Packet-Switched (PS) communication system. These conventional mobile communication systems were realized with different technologies by country and region, and there was no internationally unified standard.

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  • As discussed in the previous chapters, the International Mobile Telecommunications-2000 (IMT-2000) system is now an up-and-running system after its studies commenced in 1985 in pursuit of a future mobile communications system. IMT-2000 is expected to develop further into a more advanced and diversified system in response to growing demand and need. Efforts to make the IMT-2000 system more sophisticated are continuing at the International Telecommunication Union (ITU) and at various other organizations.

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  • CELLULAR MOBILE COMMUNICATION SYSTEMS: FROM 1G TO 4G The basic principles of cellular communications were explained in the introductory chapter, and terms such as cluster size and reuse efficiency introduced. In the following, some more considerations on the advantages and limitations of the cellular concept will be made before reviewing first generation (1G) and second generation (2G) cellular communication systems.

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  • Wireless communications is, by any measure, the fastest growing segment of the communications industry. As such, it has captured the attention of the media and the imagination of the public. Cellular systems have experienced exponential growth over the last decade and there are currently around two billion users worldwide. Indeed, cellular phones have become a critical business tool and part of everyday life in most developed countries, and are rapidly supplanting antiquated wireline systems in many developing countries....

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  • MULTIPLE ACCESS IN CELLULAR COMMUNICATION SYSTEMS To examine the problem of multiple access in cellular communications, first the relevant OSI layers need to be identified, which is not necessarily straightforward. A split into basic multiple access schemes such as CDMA, TDMA, and FDMA, associated with the physical layer, and multiple access protocols, situated at the medium access control layer, is adopted here. After a discussion of basic multiple access schemes, approaches chosen for medium access control in 2G cellular communication systems are briefly reviewed....

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  • Over many years, RF-MEMS have been a hot topic in research at the technology and device level. In particular, various kinds of mechanical Si-MEMS resonators and piezoelectric BAW (bulk acoustic wave) resonators have been developed. The BAW technology has made its way to commercial products for passive RF filters, in particular for duplexers in RF transceiver front ends for cellular communications. Beyond their use in filters, micromachined resonators can also be used in conjunction with active devices in innovative circuits and architectures.

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  • Mobility is the most important feature of a wireless cellular communication system. Usually, continuous service is achieved by supporting handoff (or handover) from one cell to another. Handoff is the process of changing the channel (frequency, time slot, spreading code, or combination of them) associated with the current connection while a call is in progress. It is often initiated either by crossing a cell boundary or by a deterioration in quality of the signal in the current channel.

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  • Ultra wideband (UWB) has advanced and merged as a technology, and many more people are aware of the potential for this exciting technology. The current UWB field is changing rapidly with new techniques and ideas where several issues are involved in developing the systems. Among UWB system design, the UWB RF transceiver and UWB antenna are the key components. Recently, a considerable amount of researches has been devoted to the development of the UWB RF transceiver and antenna for its enabling high data transmission rates and low power consumption.

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  • The fusion of computer and telecommunication technologies has heralded the age of information superhighway over wireline and wireless networks. Mobile cellular communication systems and wireless networking technologies are growing at an ever-faster rate, and this is likely to continue in the foreseeable future. Wireless technology is presently being used to link portable computer equipment to corporate distributed computing and other sources of necessary information.

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  • A book that writer feel can be useful to readers on the following fronts: as a textbook as well as a handbook, since it covers new systems and technologies, as a guide to broadband wireless access and cellular systems, as a reference book for executives, as a textbook for college seniors and graduate students.

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  • Continued advances in information technologies are enabling a growing number of physical devices to be imbued with computing and communications capabilities. Aircraft, cars, household appliances, cellular telephones, and health monitoring devices all contain microprocessors that are being linked with other information processing devices. Such examples represent only the very beginning of what is possible. As microprocessors continue to shrink, wireless radios are also becoming more powerful and compact.

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