The ever-Increasing demand for private and sensitive data transmission over wireless net- works has made security a crucial concern in the current and future large-scale, dynamic, and heterogeneous wireless communication systems. To address this challenge, computer scientists and engineers have tried hard to continuously come up with improved crypto- graphic algorithms. But typically we do not need to wait too long to find an efficient way to crack these algorithms. With the rapid progress of computational devices, the current cryptographic methods are already becoming more unreliable. In recent years, wireless re- searchers have sought a new security paradigm termed physical layer security. Unlike the traditional cryptographic approach which ignores the effect of the wireless medium, physi- cal layer security exploits the important characteristics of wireless channel, such as fading, interference, and noise, for improving the communication security against eavesdropping attacks. This new security paradigm is expected to complement and significantly increase the overall communication security of future wireless networks.
标签: Communications Physical Security Wireless Layer in
上传时间: 2020-05-31
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We are currently witnessing an increase in telecommunications norms and standards given the recent advances in this domain. The Increasing number of normalized standards paves the way for an increase in the range of offers and services available for each consumer. Moreover, the majority of available radio frequencies have already been allocated.
标签: Allocation Resource Radio
上传时间: 2020-06-01
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Wireless communications and networking technology are advancing at a very rapid pace. Newer technologies and standards are evolving to serve the ever-Increasing num- ber of users demanding different types of mobile applications and services. Research and development activities on wireless technology constitute one of the most impor- tant segments of research and development in the telecommunications area today.
标签: Management Resource Radio
上传时间: 2020-06-01
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Commoditization is a serious threat to the telecommunications industry. Most CSPs offer similar services at rates designed to win what has become a price war. As a result, many face decreasing margins and difficulty sustaining differentiation based on prices or products alone. On top of commoditization, CSPs also face competition from OTT providers and an Increasingly knowledgeable and demanding customer base. With access to growing amounts of data from an ever-Increasing number of sources and devices, today’s empowered, savvy consumers know what they want and expect to get it.
标签: RestoringConnections_IBM_CPL
上传时间: 2020-06-01
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This book was born from the perception that there is much more to spectrum use and sharing than one sees reflected in publications, whether academic, commercial or political. the former – in good research style – tend towards reductionism and concentrate on specific, detailed aspects. commercial publications tend to empha- size the positive aspects and they tend to put promise above practice. Given the ever Increasing pace of technology development and recent successes of new wireless technologies, some pundits predict large-scale spectrum scarcity, potentially lead- ing to economic catastrophe. Although economic theory has a hard time explaining recent events that shook the world economy, the notion of spectrum scarcity is intui- tively acceptable, even if not correct or immediately relevant.
上传时间: 2020-06-01
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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
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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
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The advent of modern wireless devices, such as smart phones and MID 1 terminals, has revolutionized the way people think of personal connectivity. Such devices encompass multiple applications ranging from voice and video to high-speed data transfer via wireless networks. The voracious appetite of twenty-first century users for supporting more wireless applications on a single device is ever Increasing. These devices employ multiple radios and modems that cover multiple frequency bands and multiple standards with a manifold of wireless applications often running simultaneously.
标签: Architectures Wireless Receiver Design and
上传时间: 2020-06-01
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Describing the relevant detection and estimation theory, this detailed guide provides the background knowledge needed to tackle the design of practical WLAN positioning systems. It sets out key system-level challenges and design considerations in Increasing positioningaccuracyandreducingcomputationalcomplexity,examinesdesigntradeoffs, and presents experimental results.
标签: Positioning Systems WLAN
上传时间: 2020-06-01
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Contamination and electrostatic discharge (ESD) are now becoming recognized as factors affecting yield and reliability in an ever-Increasing number of industries. Whereas contam- ination traditionally was recognized as affecting the semiconductor, disk drive, aerospace, pharmaceutical, and medical device industries, today such industries as automobile and food production are also discovering the benefits of contamination control. ESD control has experienced a similar growth in applications.
标签: Contamination Control and ESD
上传时间: 2020-06-05
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