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.
標(biāo)簽： Allocation Resource RAdio
上傳時(shí)間： 2020-06-01
上傳用戶：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.
標(biāo)簽： Management Spectrum RAdio
上傳時(shí)間： 2020-06-01
上傳用戶：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.
標(biāo)簽： Cognitive Systems Design RAdio RFIC for
上傳時(shí)間： 2020-06-01
上傳用戶：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.
標(biāo)簽： Software Defined RAdio
上傳時(shí)間： 2020-06-01
上傳用戶：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
標(biāo)簽： Software Defined RAdio for 3G
上傳時(shí)間： 2020-06-01
上傳用戶：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.
上傳時(shí)間： 2020-06-01
上傳用戶：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.
標(biāo)簽： Cognitive Networks RAdio
上傳時(shí)間： 2020-06-07
上傳用戶：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.
標(biāo)簽： Identification Frequency Sensors RAdio and
上傳時(shí)間： 2020-06-08
上傳用戶：shancjb
EIMAC Tube Catalog ( ref data) - RAdio and TV Broadcasters (z-lib.org)
標(biāo)簽： eimac
上傳時(shí)間： 2022-01-16
上傳用戶：
射頻識(shí)別(RAdio Frequency Identification，RFID)是一種允許非接觸式數(shù)據(jù)采集的自動(dòng)識(shí)別技術(shù)。其中工作在超高頻(Ultra High Frequency，UHF)頻段的無源RFID系統(tǒng)，由于在物流與供應(yīng)鏈管理等領(lǐng)域的潛在應(yīng)用，近年來得到了人們的廣泛關(guān)注。這種系統(tǒng)所使用的無源標(biāo)簽具有識(shí)別距離長(zhǎng)、體積小、成本低廉等突出特點(diǎn)。目前在市場(chǎng)上出現(xiàn)了各種品牌型號(hào)的UHF RFID無源標(biāo)簽，由于不同品牌型號(hào)的標(biāo)簽在設(shè)計(jì)與制造工藝上的差異，這些標(biāo)簽在性能表現(xiàn)上各不相同，這就給終端用戶選擇合適自己應(yīng)用的標(biāo)簽帶來了困難。RFID基準(zhǔn)測(cè)試就是在實(shí)際部署RFID系統(tǒng)前對(duì)RFID標(biāo)簽的性能進(jìn)行科學(xué)評(píng)估的有效手段。然而為了在常規(guī)實(shí)驗(yàn)室條件下得到準(zhǔn)確公正的測(cè)試結(jié)果，需要對(duì)基準(zhǔn)測(cè)試的性能指標(biāo)及測(cè)試方法學(xué)開展進(jìn)一步的研究。本文正是研究符合EPC Class1 Gen2標(biāo)準(zhǔn)的RFID標(biāo)簽基準(zhǔn)測(cè)試。 本文首先分析了當(dāng)前廣泛應(yīng)用的超高頻無源RFID標(biāo)簽基準(zhǔn)測(cè)試性能指標(biāo)與測(cè)試方法上的局限性與不足之處。例如，在真實(shí)的應(yīng)用環(huán)境中，由于受到各種環(huán)境因素的影響，對(duì)同一品牌型號(hào)的標(biāo)簽，很難得到一致的識(shí)讀距離測(cè)試結(jié)果。另外，在某些測(cè)試場(chǎng)景中，使用識(shí)讀速率作為測(cè)試指標(biāo)，所得到的測(cè)試結(jié)果數(shù)值非常接近，以致分辨度不足以區(qū)分不同品牌型號(hào)標(biāo)簽的性能差異。在這些分析基礎(chǔ)上，本文把路徑損耗引入了RFID基準(zhǔn)測(cè)試，通過有限點(diǎn)的測(cè)量與數(shù)據(jù)擬合分別得到不同類型標(biāo)簽的路徑損耗方程，結(jié)合讀寫器天線的輻射方向圖，進(jìn)一步得到各種標(biāo)簽受限于讀寫器接收靈敏度的覆蓋區(qū)域。無源標(biāo)簽由于其被動(dòng)式能量獲取方式，其實(shí)際工作區(qū)域仍然受限于前向鏈路。本文通過實(shí)驗(yàn)測(cè)試出這些標(biāo)簽的最小激活功率后，得出了各種標(biāo)簽在一定讀寫器發(fā)射功率下的激活區(qū)域。完成這些步驟后，根據(jù)這兩種區(qū)域的交集可以確定標(biāo)簽的工作區(qū)域，從而進(jìn)行標(biāo)簽間的比較并達(dá)到基準(zhǔn)測(cè)試的目的，并能找出限制標(biāo)簽工作范圍的瓶頸。 本文最后從功率損耗的角度研究了標(biāo)簽之間的相互干擾，為用戶在密集部署RFID標(biāo)簽的場(chǎng)景中設(shè)置標(biāo)簽之間的最小間隔距離具有重要的參考意義。
標(biāo)簽： 超高頻 射頻識(shí)別 基準(zhǔn)測(cè)試
上傳時(shí)間： 2013-04-24
上傳用戶：hbsunhui
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