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
上传用户:shancjb
An understanding of the policies, regulations, standards and techniques of RADIO spectrum management is useful to those who manage and administrate it, to operators, to equipment providers and to the users of wireless communication (i.e., all of us). For many years the author has been deeply involved in ruling the RF spectrum at the national, regional and global levels. The book is based on the professional experience of the author, his academic courses, presenta- tions and tutorials in five continents. The book reflects this legacy and will be of use to engineers, lawyers and economists, who serve the global industry of the wireless world; in it they may find solutions to the problems they frequently encounter.
标签: Management Spectrum RADIO
上传时间: 2020-06-01
上传用户:shancjb
Cognitive RADIOs have become a vital solution that allows sharing of the scarce frequency spectrum available for wireless systems. It has been demonstrated that it can be used for future wireless systems as well as integrated into 4G/5G wireless systems. Although there is a great amount of literature in the design of cognitive RADIOs from a system and networking point of view, there has been very limited available literature detailing the circuit implementation of such systems. Our textbook, RADIO Frequency Integrated Circuit Design for Cognitive RADIOs, is the first book to fill a disconnect in the literature between Cognitive RADIO systems and a detailed account of the circuit implementation and architectures required to implement such systems. In addition, this book describes several novel concepts that advance state-of-the-art cognitive RADIO systems.
标签: Cognitive Systems Design RADIO RFIC for
上传时间: 2020-06-01
上传用户:shancjb
Until the mid-1990s most readers would probably not have even come across the term soft- ware defined RADIO (SDR), let alone had an idea what it referred to. Since then SDR has made the transition from obscurity to mainstream, albeit still with many different understandings of the terms – software RADIO, software defined RADIO, software based RADIO, reconfigurable RADIO.
上传时间: 2020-06-01
上传用户:shancjb
Software defined RADIO (SDR) is an exciting new field for the wireless indus- try; it is gaining momentum and beginning to be included in commercial and defense products. The technology offers the potential to revolutionize the way RADIOs are designed, manufactured, deployed, and used. SDR prom- ises to increase flexibility, extend hardware lifetime, lower costs, and reduce time to market
标签: Software Defined RADIO for 3G
上传时间: 2020-06-01
上传用户:shancjb
Software RADIO (SR) is one of the most important emerging technologies for the future of wireless communication services. By moving RADIO functionality into software, it promises to give flexible RADIO systems that are multi-service, multi- standard, multi-band, reconfigurable and reprogrammable by software. Today’s RADIOs are matched to a particular class of signals that are well defined bytheircarrierfrequencies,modulationformatsandbandwidths.ARADIOtransmitter today can only up convert signals with well-defined bandwidths over defined center frequencies, while, on the other side of the communication chain, a RADIO receiver can only down convert well-defined signal bandwidths, transmitted over specified carrier frequencies.
上传时间: 2020-06-01
上传用户:shancjb
Resource allocation is an important issue in wireless communication networks. In recent decades, cognitive RADIO technology and cognitive RADIO-based networks have obtained more and more attention and have been well studied to improve spectrum utilization and to overcomethe problem of spectrum scarcity in future wireless com- munication systems. Many new challenges on resource allocation appear in cogni- tive RADIO-based networks. In this book, we focus on effective solutions to resource allocation in several important cognitive RADIO-based networks, including a cogni- tive RADIO-basedopportunisticspectrum access network, a cognitiveRADIO-basedcen- tralized network, a cognitive RADIO-based cellular network, a cognitive RADIO-based high-speed vehicle network, and a cognitive RADIO-based smart grid.
上传时间: 2020-06-07
上传用户:shancjb
There is an unprecedented enthusiasm for RADIO frequency identification (RFID) technologies today. RFID is based on the exchange of information carried by electromagnetic waves between a label, or tag, and a reader. This technology is currently in full economic expansion, which has manifested itself in widely backed research activities, some of which will be examined in this book.
标签: Identification Frequency Sensors RADIO and
上传时间: 2020-06-08
上传用户:shancjb
EIMAC Tube Catalog ( ref data) - RADIO and TV Broadcasters (z-lib.org)
标签: eimac
上传时间: 2022-01-16
上传用户:
射频识别(RADIO Frequency Identification,RFID)是一种允许非接触式数据采集的自动识别技术。其中工作在超高频(Ultra High Frequency,UHF)频段的无源RFID系统,由于在物流与供应链管理等领域的潜在应用,近年来得到了人们的广泛关注。这种系统所使用的无源标签具有识别距离长、体积小、成本低廉等突出特点。目前在市场上出现了各种品牌型号的UHF RFID无源标签,由于不同品牌型号的标签在设计与制造工艺上的差异,这些标签在性能表现上各不相同,这就给终端用户选择合适自己应用的标签带来了困难。RFID基准测试就是在实际部署RFID系统前对RFID标签的性能进行科学评估的有效手段。然而为了在常规实验室条件下得到准确公正的测试结果,需要对基准测试的性能指标及测试方法学开展进一步的研究。本文正是研究符合EPC Class1 Gen2标准的RFID标签基准测试。 本文首先分析了当前广泛应用的超高频无源RFID标签基准测试性能指标与测试方法上的局限性与不足之处。例如,在真实的应用环境中,由于受到各种环境因素的影响,对同一品牌型号的标签,很难得到一致的识读距离测试结果。另外,在某些测试场景中,使用识读速率作为测试指标,所得到的测试结果数值非常接近,以致分辨度不足以区分不同品牌型号标签的性能差异。在这些分析基础上,本文把路径损耗引入了RFID基准测试,通过有限点的测量与数据拟合分别得到不同类型标签的路径损耗方程,结合读写器天线的辐射方向图,进一步得到各种标签受限于读写器接收灵敏度的覆盖区域。无源标签由于其被动式能量获取方式,其实际工作区域仍然受限于前向链路。本文通过实验测试出这些标签的最小激活功率后,得出了各种标签在一定读写器发射功率下的激活区域。完成这些步骤后,根据这两种区域的交集可以确定标签的工作区域,从而进行标签间的比较并达到基准测试的目的,并能找出限制标签工作范围的瓶颈。 本文最后从功率损耗的角度研究了标签之间的相互干扰,为用户在密集部署RFID标签的场景中设置标签之间的最小间隔距离具有重要的参考意义。
上传时间: 2013-04-24
上传用户:hbsunhui