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.
标签： HSDPAHSUPA Access Speed Radio UMTS High for
上传时间： 2020-05-27
上传用户：shancjb
This book addresses two aspects of network operation quality; namely, resource management and fault management. Network operation quality is among the functions to be fulfilled in order to offer quality of service, QoS, to the end user. It is characterized by four parameters: – packet loss; – delay; – jitter, or the variation of delay over time; – availability. Resource management employs mechanisms that enable the first three parameters to be guaranteed or optimized. Fault management aims to ensure continuity of service.
标签： Ethernet Networks MPLS and IP
上传时间： 2020-05-27
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In recent years, the research and developments in the area of RF and microwave technologies have progressed significantly due to the growing demand for applica- bility in wireless communication technologies. Starting from 1992, wireless com- munication technologies have become quite mature. In the modern era of electronic developments, design of wireless handsets is an example of integration of many di- verse skill sets. Classical books in the areas of microwave technology provide us with an in-depth knowledge of electromagnetic fundamentals.
标签： front-Ends Receiver Modern
上传时间： 2020-05-31
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This book is about multipoint cooperative communication, a key technology to overcome the long-standing problem of limited transmission rate caused by inter- point interference. However, the multipoint cooperative communication is not an isolated technology. Instead, it covers a vast range of research areas such as the multiple-input multiple-outputsystem, the relay network, channel state information issues, inter-point radio resource management operations, coordinated or joint transmissions, etc. We suppose that any attempt trying to thoroughly analyze the multipoint cooperative communication technology might end up working on a cyclopedia for modern communication systems and easily get lost in discussing all kinds of cooperative communication schemes as well as the associated models and their variations.
标签： Communication Multi-point Cooperative Systems
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The unguided transmission of information using electromagnetic waves at radio frequency (RF) is often referred to as wireless communications, the first demonstration of which took place at the end of the 19th cen- tury and is attributed to Hertz. The technology was, shortly thereafter, commercialised by, amongst others, Marconi in one of the first wire- less communication systems, i.e., wireless telegraphy. In the first half of the 20th century the technology was developed further to enable more than the mere transmission of Morse code. This first resulted in uni- directional radio broadcasting and several years later also in television broadcasting.
标签： Imperfections RF
上传时间： 2020-06-01
上传用户：shancjb
The following sections profile many of the vendors in the NFV market. The individual profiles were created through a collaborative effort between SDNCentral’s Research Team and the Vendor’s product experts. SDNCentral worked under the assumption the information provided by the vendors was factual, auditing the submissions only to remove unverifiable claims and hyperbole. Extended profiles can be viewed online. While every attempt has been made to validate the capabilities listed in the profiles, SDNCentral advises end users to verify the veracity of each claim for themselves in their actual deployment environments. SDNCentral cannot be held liable for unexpected operations, damages or incorrect operation due to any inaccuracies listed here. SDNCentral welcomes feedback and additional information from end users based on their real-world experiences with the products and technologies listed. The SDNCentral research team can be reached at
标签： SDxCentral-Mega-NFV-Report
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Ultra-wideband (UWB) technology enables high data-rate short-range communica- tion, in excess of hundredmegabit-per-secondsand up to multi-gigabit-per-seconds, over a wide spectrum of frequencies, while keeping power consumption at low lev- els. This low power operation results in a less-interfering co-existence with other existed communication technologies (e.g., UNII bands). In addition to carrying a huge amount of data over a distance of up to 230 feet at very low power (less than 0.5mW), the UWB signal has the ability to penetrate through the doors and other obstacles that tend to reflect signals at more limited bandwidths and higher power densities.
标签： Silicon-Based front-Ends RF
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The first practical examples of mobile communications were used in many countries like the USA, the UK and Germany in military services, and played a significant role in the First World War to transfer important information from the front to headquarters to take further actions. Good and secure wireless communications were an important need for all military services – army, navy and air force. In this respect, the Second World War was a big experimental battlefield for the development and evolution of mobile radio. It was in the interests of governments that after the Second World War the military investment should be paid back by civilian use, and all western European countries started their so-called first generation of mobile communication networks.
标签： Multimedia Business Mobile The
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A wireless ad-hoc network is a wireless network deployed without any infrastructure. In such a network, there is no access point or wireless router to forward messages among the computing devices. Instead, these devices depend on the ad-hoc mode of their wireless net‐ work interface cards to communicate with each other. If the nodes are within the transmis‐ sion range of the wireless signal, they can send messages to each other directly. Otherwise, the nodes in between will forward the messages for them. Thus, each node is both an end system and a router simultaneously.
上传时间： 2020-06-01
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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
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