The continuing explosive growth in mobile communication is demanding more spectrally efficient radio access technologies than the prevalent second GeneratIOn (2G) systems such as GSM to handle just the voice traffic. We are already witnessing high levels of mobile penetration exceeding 70% in some countries. It is anticipated that by 2010 more than half of all communications will be carried out by mobile cellular networks. On the other hand, the information revolution and changing life habits are bringing the requirement of commu- nicating on a multimedia level to the mobile environment. But the data handling capabilities and flexibility of the 2G cellular systems are limited.
上传时间: 2020-06-01
上传用户:shancjb
Second-GeneratIOn telecommunication systems, such as the Global System for Mobile Communications (GSM), enabled voice traffic to go wireless: the number of mobile phones exceeds the number of landline phones and the mobile phone penetration is approaching 100% in several markets. The data-handling capabilities of second-GeneratIOn systems are limited, however, and third-GeneratIOn systems are needed to provide the high bit-rate services that enable high-quality images and video to be transmitted and received, and to provide access to the Web with higher data rates.
标签: Evolution WCDMA UMTS HSPA LTE for and
上传时间: 2020-06-01
上传用户:shancjb
This book is an outgrowth of the pioneering development work done by InterDigital Com- munication Corporation in 3rd GeneratIOn TDD WCDMA Technology. Many engineers and managers were involved in this development, which spanned a wide range of tech- nology areas, including system architecture, radio interface, radio modem design, radio resource management and hardware/software implementation. In addition, TDD WCDMA technology had many direct and indirect contributors across the globe in the context of the development of the 3GPP TDD WCDMA Standard.
上传时间: 2020-06-01
上传用户:shancjb
During the past three decades, the world has seen signifi cant changes in the telecom- munications industry. There has been rapid growth in wireless communications, as seen by large expansion in mobile systems. Wireless communications have moved from fi rst-GeneratIOn (1G) systems primarily focused on voice communications to third-GeneratIOn (3G) systems dealing with Internet connectivity and multi-media applications. The fourth-GeneratIOn (4G) systems will be designed to connect wire- less personal area networks (WPANs), wireless local area networks (WLANs) and wireless wide-area networks (WWANs).
标签: Communications Networking Wireless
上传时间: 2020-06-01
上传用户:shancjb
Wirelesscommunications,especiallyinitsmobileform,hasbroughtusthefreedomofmobility andhaschangedthelifestylesofmodernpeople.Waitingatafixedlocationtoreceiveormakea phone call, or sitting in front of a personal computer to send an e-mail or download a video program, has become an old story. Nowadays it is commonplace for people to talk over a cell phonewhilewalkingonthestreet,ortodownloadandwatchamoviewhiletravelingonatrain. Thisisthebenefitmadeavailabletousbythesuccessfulevolutionofwirelesscommunications over three GeneratIOns, with the fourth GeneratIOn being under way.
标签: Communications Management Wireless Resource
上传时间: 2020-06-01
上传用户:shancjb
Wireless Mesh Networks (WMN) are believed to be a highly promising technology and will play an increasingly important role in future GeneratIOn wireless mobile networks. WMN is characterized by dynamic self-organization, self-configuration and self-healing to enable quick deployment, easy maintenance, low cost, high scalability and reliable services, as well as enhancing network capacity, connect- ivity and resilience.
标签: Networking Wireless Mesh
上传时间: 2020-06-01
上传用户:shancjb
This chapter provides extensive coverage of existing mobile wireless technologies. Much of the emphasis is on the highly anticipated 3G cellular networks and widely deployed wireless local area networks (LANs), as the next-GeneratIOn smart phones are likely to offer at least these two types of connectivity. Other wireless technologies that either have already been commercialized or are undergoing active research and standardization are introduced as well. Because standardization plays a crucial role in developing a new technology and a market, throughout the discussion standards organizations and industry forums or consortiums of some technologies are introduced. In addition, the last section of this chapter presents a list of standards in the wireless arena.
标签: Networking Wireless Complete
上传时间: 2020-06-01
上传用户:shancjb
This book paves the path toward fourth GeneratIOn (4G) mobile communica- tion by introducing mobility in heterogeneous IP networks with both third GeneratIOn (3G) and wireless local area networks (WLANs), which is seen as one of the central issues in the becoming 4G of telecommunications networks and systems. This book presents a thorough overview of 3G networks and standards and discusses interworking and handover mechanisms between WLANs and the Universal Mobile Telecommunication System (UMTS).
标签: Wireless towards WLANs WPANs 4G
上传时间: 2020-06-01
上传用户:shancjb
Electricity has been chosen as the most convenient and useful form of energy, due to its ease of transportation over large distances and easy conversion to other energy forms. The biggest inconvenience with electricity is that it cannot be stored and must be utilized at the moment of GeneratIOn. The storage of a large amount of electrical energy is usually connected with its conversion to other types of energy, which significantly reduces the efficiency of such processes. The aim of the power system, often treated as the biggest and the most complex machine ever built, is to deliver uninterruptible electric energy of demanded quality parameters to consumers.
标签: Electromagnetic Interference Conducted
上传时间: 2020-06-07
上传用户:shancjb
This book is written for engineers involved in the operation, control, and planning of electric power systems. In addition, the book provides information and tools for researchers working in the fields of power system security and stability. The book consists of two volumes. The first volume provides traditional techniques for the stability analysis of large scale power systems. In addition, an overview of the main drivers and requirements for modernization of the traditional methods for online applications are discussed. The second volume provides techniques for online security assessment and corrective action studies. In addition, the impact of variable GeneratIOn on the security of power systems is considered in the second volume. The first volume may be considered as a background builder while the second volume is intended for the coverage of edge techniques and methods for online dynamic security studies.
上传时间: 2020-06-07
上传用户:shancjb