The radio spectrum is one of the most precious resources which must be managed to ensure efficient access for the wireless communication ServiCEs which use it. The allocation and management of spectrum are administered by the regulatory authorities. Traditionally, spectrum allocation is carried out exclusively of its use in large geographic areas and assigning frequency bands to specific users or ServiCE providers is proved to be inefficient. Recently, substantial knowledge about dynamic spectrum access scheme has been accumulated to enable efficient spectrum sharing.
标签： Management Spectrum Access and
上传时间： 2020-06-01
上传用户：shancjb
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
上传用户：shancjb
Rapid progress in information and communications technology (ICT) induces improved and new telecommunications ServiCEs and contributes greatly to society in general and to vendors and network and ServiCE providers. In addition to existing ServiCEs such as telephony or leased line ServiCEs, spread of the Internet, the Internet Protocol (IP) phone, and new communications ServiCEs like IPTV are making great progress with the development of digital subscriber lines (DSL) and high - speed communications technologies like fi ber to the home (FTTH).
标签： Telecommunications Networks
上传时间： 2020-06-01
上传用户：shancjb
When 3GPP started standardizing the IMS a few years ago, most analysts expected the number of IMS deploymentsto grow dramatically as soon the initial IMS specifications were ready (3GPP Release 5 was functionallyfrozenin the first half of 2002and completedshortly after that). While those predictions have proven to be too aggressive owing to a number of upheavals hitting the ICT (Information and Communications Technologies) sector, we are now seeing more and more commercial IMS-based ServiCE offerings in the market. At the time of writing (May 2008), there are over 30 commercial IMS networks running live traffic, addingup to over10million IMS users aroundthe world; the IMS is beingdeployedglobally. In addition, there are plenty of ongoing market activities; it is estimated that over 130 IMS contracts have been awarded to all IMS manufacturers. The number of IMS users will grow substantially as these awarded contracts are launched commercially. At the same time, the number of IMS users in presently deployed networks is steadily increasing as new ServiCEs are introduced and operators running these networks migrate their non-IMS users to their IMS networks.
标签： Multimedia Subsystem The IMS 3G IP
上传时间： 2020-06-01
上传用户：shancjb
Fourth Generation (4G) wireless communication systems aim to allow peak data rates in the range of 1 Gbps for nomadic access and 100 Mbps for vehicular mobil- ity. 4G aims to support current and emergent multimedia ServiCEs, such as mobile TV, social networks and gaming, high-definition television and video telecon- ference, multimedia messaging ServiCE, using the All-over IP concept and with improved quality of ServiCE.
标签： Transmission Techniques Systems for 4G
上传时间： 2020-06-01
上传用户：shancjb
Having dealt with in-depth analysis of SS#7, GSM and GPRS networks I started to monitor UTRAN interfaces approximately four years ago. Monitoring interfaces means decoding the data captured on the links and analysing how the different data segments and messages are related to each other. In general I wanted to trace all messages belonging to a single call to prove if the network elements and protocol entities involved worked fine or if there had been failures or if any kind of suspicious events had influenced the normal call proceeding or the call’s quality of ServiCE. Cases showing normal network behaviour have been documented in Kreher and Ruedebusch (UMTS Signaling. John Wiley & Sons, Ltd, 2005), which provides examples for technical experts investigating call flows and network procedures.
标签： Performance Measurement Practical Guide UMTS
上传时间： 2020-06-01
上传用户：shancjb
Once upon a time, cellular wireless networks provided two basic ServiCEs: voice telephony and low-rate text messaging. Users in the network were separated by orthogonal multiple access schemes, and cells by generous frequency reuse patterns [1]. Since then, the proliferation of wireless ServiCEs, fierce competition, andthe emergenceof new ServiCE classes such as wireless data and multimediahave resulted in an ever increasing pressure on network operators to use resources in a moreefficient manner.In the contextof wireless networks,two of the most common resources are power and spectrum—and, due to regulations, these resources are typically scarce. Hence, in contrast to wired networks, overprovisioning is not feasible in wireless networks.
标签： Maximization Nonconvex Wireless Utility Systems in
上传时间： 2020-06-01
上传用户：shancjb
Mobile radio communications are evolving from pure telephony systems to multimedia platforms offering a variety of ServiCEs ranging from simple file transfers and audio and video streaming, to interactive applications and positioning tasks. Naturally, these ServiCEs have different constraints concerning data rate, delay, and reliability (quality-of-ServiCE (QoS)). Hence, future mobile radio systems have to provide a large flexibility and scal- ability to match these heterogeneous requirements.
标签： Communications Wireless Channels MIMO over
上传时间： 2020-06-01
上传用户：shancjb
The wide deployment of wireless networks and mobile technologies, along with the significant increase in the number of mobile device users, have created a very strong demand on various wireless-based, mobile-based software application systems and enabling technologies. This not only provides many new business opportunities and challenges to wireless and networking ServiCE providers, mobile technology ven- dors, and software industry and solution integrators, butalso changes and enhances people’s lives in many areas, including communications, information sharing and exchange, commerce, home environment, education, and entertainment. Business organizations and government agencies face new pressure fortechnology updatesto upgrade their networking infrastructures with wireless connectivity to enhance enterprise-oriented systems and solutions.
标签： Wireless-Based Software Systems
上传时间： 2020-06-01
上传用户：shancjb
With the proliferation of cloud computing and Internet online ServiCEs, more and more data and computation are migrated to geographical distributed Internet data centers (IDCs), which can provide reliability, management, and cost benefits. However, IDC operators encounter several major problems in IDC operations, such as huge energy consumption and energy cost, and high carbon emission. To deal with the above problems, IDC operators have to efficiently manage the way of energy consumption and energy supply. Considering the potential of smart grid, we focus on the energy management of IDCs in smart grid from several perspectives, i.e., power outage, carbon emission, heterogeneous ServiCE delay guarantees, and operation risk.
上传时间： 2020-06-07
上传用户：shancjb
