通信工程移动通信中英文对照外文翻译文献

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通信类中英文翻译、外文文献翻译

美国科罗拉多州大学关于在噪声环境下对大量连续语音识别系统的改进---------噪声环境下说话声音的识别工作简介在本文中，我们报道美国科罗拉多州大学关于噪声环境下海军研究语音词汇系统方面的最新改进成果。

特别地,我们介绍在有限语音数据的前提下，为了了解不确定观察者和变化的环境的任务(或调查方法)，我们必须在提高听觉和语言模式方面努力下工夫。

在大量连续词汇语音识别系统中,我们将展开MAPLR自适应方法研究。

它包括单个或多重最大可能线形回归。

当前噪声环境下语音识别系统使用了大量声音词汇识别的声音识别引擎。

这种引擎在美国科罗拉多州大学目前得到了飞速的发展，本系统在噪声环境下说话声音系统(SPINE-2)评价数据中单词错识率表现为30.5%，比起2001年的SPINE-2来,在相关词汇错识率减少16%。

1.介绍为获得噪声环境下的有活力的连续声音系统的声音，我们试图在艺术的领域做出计算和提出改善，这个工作有几方面的难点：依赖训练的有限数据工作；在训练和测试中各种各样的军事噪声存在；在每次识别适用性阶段中，不可想象的听觉溪流和有限数量的声音。

在2000年11月的SPIN-1和2001年11月SPIN-2中，海军研究词汇通过DARPT在工作上给了很大的帮助。

在2001年参加评估的种类有：SPIIBM,华盛顿大学，美国科罗拉多州大学，AT&T,奥瑞哥研究所，和梅隆卡内基大学。

它们中的许多先前已经报道了SPINE-1和SPLNE-2工作的结果。

在这方面的工作中不乏表现最好的系统.我们在特性和主模式中使用了自适应系统，同时也使用了被用于训练各种参数类型的多重声音平行理论(例如MFCC、PCP等)。

其中每种识别系统的输出通常通过一个假定的熔合的方法来结合。

这种方法能提供一个单独的结果，这个结果的错误率将比任何一个单独的识别系统的结果要低。

美国科罗拉多州大学参加了SPIN-2和SPIN-1的两次评估工作。

我们2001年11月的SPIN-2是美国科罗拉多州大学识别系统基础上第一次被命名为SONIC(大量连续语音识别系统)的。

GPS 通信系统外文翻译外文文献英文文献全球移动通信系统

译文全球移动通信系统移动系统跨越世界性成功标志是越来越朝着个人化、方便化方向发展。

在商业活动中，人们必须使用移动电话，以便无论何时何地都能实现电话的功能。

在快速的个人生活中，移动电话已成为一种必须，而不仅仅是为了方便。

不像固定通信系统那样，很大程度上依靠技术和通信标准，移动通信系统随着个人通信系统的革命而发生变化。

对移动通信系统而言，要获得调整后的武夫，有三个关键因素，即价格、电话的大小和重量以及网络的花费和质量。

如果上述因素实现有困难，特别是前两个，那么市场的发展将严格受限。

固定电话的服务是全球的，相互联系的范围从同轴电缆到光纤，以及人造卫星。

世界通信标准是不同的，但随着普通接口以及对接口转化，相互之间的联系能发生改变。

随着漫游的创建，需要一个复杂的网络工作系统，这对于移动通信而言是一个非常复杂的问题。

因此，移动通信的通信标准问题比固定通信系统标准问题更关键，此外，在移动通信领域无线电频谱分配问题也非常使人烦恼。

移动通信系统是最初工作在频带为450MHz模拟方式（现在仍然有），后来随着数字式GSM发展，工作在频带为900 MHz，之后随着个人通信系统的发展，工作的频带为1800 MHz。

移动通信系统的历史可分为几代。

第一代为美国的先进移动电话系统（AMPS），欧洲大部分的全通路通信系统（TACS），以及北欧的移动电话系统（NMTS），这些都是模拟系统。

第二代由第一个非常标准的计划支配这个计划由欧洲特殊移动通信系统委员会（GSM）制定，这个设计作为全球移动通信系统。

GSM系统基于蜂窝通信原理，其最早作为一个概念由美国贝尔实验室的工程师们提出，这一思想出自于增加网络容量的需要以及解决网络堵塞的问题。

在人口稠密地区运行的广播式移动网络系统会由于很少的几个用户同时呼叫而引起堵塞。

蜂窝系统的功能在于允许频率复用。

蜂窝的概念由两个特征定义，即频率复用和小区分裂。

频率复用的区域相隔非常远，不会产生同一通道的干扰问题。

通信工程专业英语文献翻译

Multi-Code TDMA (MC-TDMA) for Multimedia Satellite Communications用于多媒体卫星通信的MC--TDMA（多码时分多址复用）R. Di Girolamo and T. Le-NgocDepartment ofa Electricl and Computer Engineering - Concordia University1455 de Maisonneuve Blvd. West, Montreal, Quebec, Canada, H3G 1M8 ABSTRACT摘要In this paper, we propose a multiple access scheme basedon a hybrid combination of TDMA and CDMA,在这篇文章中，我们提出一种基于把时分多址复用和码分多址复用集合的多址接入方案。

referred toas multi-code TDMA (MC-TDMA). 称作多码—时分多址复用The underlying TDMAframe structure allows for the transmission of variable bitrate (VBR) information,以TDMA技术为基础的帧结构允许传输可变比特率的信息while the CDMA provides inherentstatistical multiplexing.和CDMA提供固有的统计特性多路复用技术The system is studied for a multimediasatellite environment with long-range dependentdata traffic,and VBR real-time voice and video traffic研究这个系统是为了在远程环境下依赖数据传输和可变比特率的语音和视频传输的多媒体卫星通信系统 . Simulationresults show that with MC-TDMA, the data packetdelay and the probability of real-time packet loss can bemaintained low. 仿真结果表明：采用MC-TDMA的多媒体卫星通信，数据包延时和实时数据丢失的可能性可以保持很低。

现代移动通信毕业论文外文翻译 (2)

一、英文原文Modern mobile communication technologyIn now highly the information society, the information and the correspondence have become the modern society “the life”. The information exchange mainly relies on the computer correspondence, but corresponds takes the transmission method, with the sensing technology, the computer technology fuses mutually, has become in the 21st century the international society and the world economic development powerful engine. In order to of adapt the time request, the new generation of mobile communication technology seasonable and lives, the new generation of mobile communication technology is the people said that third generation's core characteristic is the wide band addressing turns on non-gap roaming between the rigid network and numerous different communications system's, gains the multimedia communication services.Along with the time progress, the technical innovation, people's life request's enhancement, the mobile communication technology renewal speed is quite astonishing, almost every other ten year mobile communication technology has a transformation update, from the 1980s “the mobile phone” to present's 3G handset, during has had two mobile communication technology transformation, transits from 1G AMPS to 2G GSM, from GSM to IMT-2000 (i.e. 3G technology). Knows modern on me the mobile communication technology to have the following several aspect important technology:1. wideband modulation and multiple access techniqueThe wireless high speed data transmission cannot only depend on the frequency spectrum constantly the expansion, should be higher than the present number magnitude at least in the frequency spectrum efficiency, may use three technologies in the physical level, namely OFDM, UWB and free time modulation code. OFDM with other encoding method's union, nimbly OFDM and TDMA, FDMA, CDMA, SDMA combines the multiple access technique.In the 1960s the OFDM multi-channel data transmission has succeeded uses in complex and the Kathryn high frequency military channels. OFDM has used in 1.6 M bit/s high bit rate digital subscriber line (HDSL), 6 M bit/s asymmetrical digital subscriber line (ADSL), 100 M bit/s really high speed figure subscriber's line (VDSL), digital audio frequency broadcast and digital video broadcast and so on. OFDM applies on 5 GHz provides 54 M bit/s wireless local network IEEE 802.11 a and IEEE 802.11g, high performance this region network Hi per LAN/2 and ETSI-BRAN, but also takes metropolitan area network IEEE 802.16 and the integrated service digit broadcast (ISDB-T) the standard. Compares with the single load frequency modulation system service pattern, the OFDM modulation service pattern needs to solve the relatively big peak even power ratio (PAPR, Peak to Average Power Ratio) and to the frequency shifting and the phase noise sensitive question.High speed mobile communication's another request is under the wide noise bandwidth, must demodulate the signal-to-noise ratio to reduce as far as possible, thus increases the cover area. May adopt the anti-fading the full start power control and the pilot frequency auxiliary fast track demodulation technology, like the frequency range anti-fading's Rake receive and the track technology, the OFDMA technology which declines from the time domain and the frequencyrange resistance time and the frequency selectivity, the link auto-adapted technology, the union coding technique.2. frequency spectrum use factor lift techniqueThe fundamental research pointed out: In the independent Rayleigh scattering channel, the data rate and the antenna several tenth linear relationships, the capacity may reach Shannon 90%. Is launching and the receiving end may obtain the capacity and the frequency spectrum efficiency gain by the multi-antenna development channel space. The MIMO technology mainly includes the spatial multiplying and the space diversity technology, concurrent or the salvo same information enhances the transmission reliability on the independent channel.Receives and dispatches the bilateral space diversity is the high-capacity wireless communication system uses one of technical. Bell Lab free time's opposite angle BLAST (D-BLAST) capacity increase to receive and dispatch the bilateral smallest antenna number in administrative levels the function. The cross time domain which and the air zone expansion signal constitutes using MIMO may also resist the multi-diameter disturbance. V-BLAST system when indoor 24~34 dB, the frequency spectrum use factor is 20~40 bit/s/Hz. But launches and the receiving end uses 16 antennas, when 30 dB, the frequency spectrum use factor increases to 60~70 bit/s/Hz.The smart antenna automatic tracking needs the signal and the auto-adapted free time processing algorithm, produces the dimensional orientation wave beam using the antenna array, causes the main wave beam alignment subscriber signal direction of arrival through the digital signal processing technology, the side lobe or zero falls the alignment unwanted signal direction of arrival. The auto-adapted array antennas (AAA, Adaptive Array Antennas) disturbs the counter-balance balancer (ICE, Interference Canceling Equalizer) to be possible to reduce disturbs and cuts the emissive power.3. software radio technologyThe software radio technology is in the hardware platform through the software edition by a terminal implementation different system in many kinds of communication services. It uses the digital signal processing language description telecommunication part, downloads the digital signal processing hardware by the software routine (DSPH, Digital Signal Processing Hardware). By has the general opening wireless structure (OWA, Open Wireless Architecture), compatible many kinds of patterns between many kinds of technical standards seamless cut.UWB is also called the pulse to be radio, the modulation uses the pulse width in the nanosecond level fast rise and the drop pulse, the pulse cover frequency spectrum from the current to the lucky hertz, does not need in the radio frequency which the convention narrow band frequency modulation needs to transform, after pulse formation, may deliver directly to the antenna launch.4. software radio technologyThe software radio technology is in the hardware platform through the software edition by a terminal implementation different system in many kinds of communication services. It uses the digital signal processing language description telecommunication part, downloads the digital signal processing hardware by the software routine (DSPH, Digital Signal Processing Hardware). By has the general opening wireless structure (OWA, Open Wireless Architecture), compatible many kinds of patterns between many kinds of technical standards seamless cut.5. network security and QoSQoS divides into wireless and the wired side two parts, wireless side's QoS involves theradio resource management and the dispatch, the admission control and the mobility management and so on, the mobility management mainly includes the terminal mobility, individual mobility and service mobility. Wired side's QoS involves based on the IP differ discrimination service and the RSVP end-to-end resources reservation mechanism. Mechanism maps the wireless side IP differ IP the QoS. Network security including network turning on security, core network security, application security, safety mechanism visibility and configurable.In the above modern mobile communication key technologies' foundation, has had the land honeycomb mobile communication, the satellite communication as well as the wireless Internet communication, these mailing address caused the correspondence appearance to have the huge change, used the digital technique the modern wireless communication already to permeate the national economy each domain and people's daily life, for this reason, we needed to care that its trend of development, hoped it developed toward more and more convenient people's life's direction, will let now us have a look at the modern mobile communication the future trend of development.modern mobile communication technological development seven new tendencies :First, mobility management already from terminal management to individual management and intelligent management developmentSecond, network already from synchronized digital circuit to asynchronous digital grouping and asynchronous transfer mode (ATM) development;the three, software's developments actuated from the algorithm to the procedure-oriented and face the goal tendency development;the four, information processing have developed from the voice to the data and the image;five, wireless frequency spectrum processing already from narrow band simulation to the narrow band CDMA development;the six, computers have developed from central processing to the distributional server and intellectualized processing;the seven, semiconductor devices have developed from each chip 16,000,000,000,000 /150MHz speed VLSI to 0.5 /350MHz speed VLSI and 2,000,000,000,000,000 /550MHz speed VLSI.Under this tendency's guidance, the mobile service rapid development, it satisfied the people in any time, any place to carry on the correspondence with any individual the desire. The mobile communication realizes in the future the ideal person-to-person communication service way that must be taken. In the information support technology, the market competition and under the demand combined action, the mobile communication technology's development is progresses by leaps and bounds, presents the following several general trends: work service digitization, grouping; 2. networking wide band; working intellectualization; 4.higher frequency band; 5. more effective use frequency; 6.each kind of network tends the fusion. The understanding, grasps these tendencies has the vital practical significance to the mobile communication operator and the equipment manufacturer.二、英文翻译现代移动通信在当今高度信息化的社会，信息和通信已成为现代社会的“命脉”。

[最新]通信专业的外文及外文翻译

Research,,,,,on,,,,,Carrier,,,,,T racking,,,,,in,,,,,Hybrid,,, ,,DS/FH,,,,,Spread,,,,,Spectrum,,,,,TT&C,,,,,SystemAbstractBecause,,,,,of,,,,,the,,,,,effect,,,,,of,,,,,carrier,,,,,frequency,,,,,hopping,,,,,,the,,,,,inp ut,,,,,IF,,,,,signal,,,,,of,,,,,carrier,,,,,tracking,,,,,loop,,,,,in,,,,,DS/FHSS,,,,,(Direct,,,,,Sequ ence/Frequency,,,,,Hopping,,,,,Spread,,,,,Spectrum),,,,,TT&C,,,,,(Telemetry,,,,,,Trackin g,,,,,&,,,,,Command),,,,,System,,,,,is,,,,,characterized,,,,,by,,,,,the,,,,,Doppler,,,,,frequen cy,,,,,agile.,,,,,The,,,,,tracking,,,,,loop,,,,,will,,,,,shift,,,,,to,,,,,the,,,,,frequency,,,,,step,,,,, response,,,,,state,,,,,ceaselessly,,,,,and,,,,,the,,,,,measurement,,,,,resolution,,,,,severely,,, ,,decline,,,,,,even,,,,,the,,,,,loop,,,,,is,,,,,likely,,,,,to,,,,,be,,,,,unlocked.,,,,,This,,,,,paper,,,, ,presents,,,,,a,,,,,carrier,,,,,tracking,,,,,loop,,,,,aided,,,,,by,,,,,frequency,,,,,hopping,,,,,pat tern.,,,,,In,,,,,order,,,,,to,,,,,keep,,,,,the,,,,,stability,,,,,of,,,,,the,,,,,tracking,,,,,loop,,,,,,the,, ,,,Doppler,,,,,frequency,,,,,agility,,,,,in,,,,,the,,,,,next,,,,,frequency,,,,,hopping,,,,,dwell,,,, ,is,,,,,estimated,,,,,and,,,,,timely,,,,,compensated,,,,,to,,,,,the,,,,,frequency,,,,,adjustment, ,,,,of,,,,,carrier,,,,,NCO,,,,,according,,,,,to,,,,,the,,,,,preset,,,,,frequency,,,,,hopping,,,,,pat tern,,,,,and,,,,,current,,,,,spacecraft,,,,,velocity.,,,,,Simulation,,,,,results,,,,,show,,,,,that,,, ,,this,,,,,method,,,,,effectively,,,,,eliminates,,,,,the,,,,,instability,,,,,due,,,,,to,,,,,carrier,,,,, frequency,,,,,hopping,,,,,,and,,,,,the,,,,,resolution,,,,,of,,,,,loop,,,,,meets,,,,,the,,,,,require ment,,,,,of,,,,,TT&C,,,,,system.,,,,,Keywords：carrier,,,,,tracking；DS/FHSS；frequency,,,,,agility；aided；TT&CI．INTRODUCTIONThe,,,,,main,,,,,function,,,,,of,,,,,TT&C,,,,,(Telemetry,,,,,,Tracking,,,,,and,,,,,Com mand),,,,,system,,,,,is,,,,,ranging,,,,,and,,,,,velocity,,,,,measurement.,,,,,Presently,,,,,,the, ,,,,most,,,,,common,,,,,used,,,,,TT&C,,,,,systems,,,,,are,,,,,unit,,,,,carrier,,,,,system,,,,,an d,,,,,unit,,,,,spread,,,,,spectrum,,,,,system.,,,,,For,,,,,the,,,,,unit,,,,,carrier,,,,,TT&C,,,,,sys tem,,,,,,ranging,,,,,is,,,,,realized,,,,,by,,,,,measuring,,,,,the,,,,,phase,,,,,difference,,,,,betw een,,,,,transmitted,,,,,and,,,,,received,,,,,tones,,,,,,and,,,,,for,,,,,the,,,,,unit,,,,,spread,,,,,sp ectrum,,,,,TT&C,,,,,system,,,,,,according,,,,,to,,,,,the,,,,,autocorrelation,,,,,properties,,,,, of,,,,,PN,,,,,code,,,,,,ranging,,,,,is,,,,,realized,,,,,by,,,,,measuring,,,,,the,,,,,phase,,,,,delay, ,,,,between,,,,,the,,,,,received,,,,,and,,,,,local,,,,,pseudonoise,,,,,(PN),,,,,code.,,,,,V elocity ,,,,,measurement,,,,,in,,,,,both,,,,,of,,,,,TT&C,,,,,systems,,,,,depends,,,,,on,,,,,extracting,, ,,,the,,,,,frequency,,,,,difference,,,,,resulting,,,,,from,,,,,the,,,,,Doppler,,,,,phenomena,,,,, between,,,,,the,,,,,transmitted,,,,,and,,,,,received,,,,,carrier.,,,,,While,,,,,all,,,,,the,,,,,proc esses,,,,,mentioned,,,,,above,,,,,are,,,,,finished,,,,,on,,,,,the,,,,,ground,,,,,of,,,,,high,,,,,res olution,,,,,carrier,,,,,tracking,,,,,,and,,,,,the,,,,,phase,,,,,lock,,,,,loop,,,,,is,,,,,the,,,,,comm on,,,,,used,,,,,method,,,,,to,,,,,implement,,,,,it,,,,,in,,,,,TT&C,,,,,system.,,,,,As,,,,,the,,,,,s pace,,,,,electromagnetism,,,,,environment,,,,,become,,,,,more,,,,,and,,,,,more,,,,,complic ated,,,,,,the,,,,,capability,,,,,of,,,,,anti-jamming,,,,,is,,,,,required,,,,,by,,,,,the,,,,,future,,,,, TT&C,,,,,system,,,,,[1].,,,,,So,,,,,we,,,,,consider,,,,,using,,,,,the,,,,,hybrid,,,,,DS/FHSS,,,, ,(Direct,,,,,Sequence/Frequency,,,,,Hopping,,,,,Spread,,,,,Spectrum),,,,,technology,,,,,to ,,,,,build,,,,,a,,,,,more,,,,,robust,,,,,TT&C,,,,,system.,,,,,,,,,,For,,,,,many,,,,,ordinary,,,,,hybrid,,,,,DS/FHSS,,,,,communication,,,,,systems,,,,,,th e,,,,,most,,,,,important,,,,,function,,,,,is,,,,,demodulating,,,,,data,,,,,but,,,,,not,,,,,measuri ng,,,,,,so,,,,,it,,,,,is,,,,,not,,,,,necessary,,,,,to,,,,,measure,,,,,the,,,,,carrier,,,,,frequency,,,,,p recisely.,,,,,However,,,,,,in,,,,,hybrid,,,,,DS/FHSS,,,,,TT&C,,,,,system,,,,,,measuring,,,,, and,,,,,tracking,,,,,the,,,,,carrier,,,,,precisely,,,,,is,,,,,the,,,,,foundation,,,,,of,,,,,system,,,,, ,so,,,,,some,,,,,special,,,,,problem,,,,,needs,,,,,to,,,,,be,,,,,solved.,,,,,In,,,,,the,,,,,hybrid,,,, ,DS/FHSS,,,,,TT&C,,,,,system,,,,,,even,,,,,the,,,,,received,,,,,signal,,,,,has,,,,,been,,,,,de hopped,,,,,by,,,,,the,,,,,pattern,,,,,synchronization,,,,,module,,,,,,due,,,,,to,,,,,the,,,,,Dopp ler,,,,,Effect,,,,,and,,,,,carrier,,,,,frequency,,,,,hopping,,,,,,the,,,,,input,,,,,frequency,,,,,of, ,,,,tracking,,,,,loop,,,,,contains,,,,,frequency,,,,,agility,,,,,severely.,,,,,As,,,,,a,,,,,result,,,,,, the,,,,,loop,,,,,is,,,,,likely,,,,,to,,,,,shift,,,,,to,,,,,the,,,,,frequency,,,,,step,,,,,responses,,,,,state,,,,,again,,,,,and,,,,,again,,,,,,and,,,,,it,,,,,seems,,,,,to,,,,,be,,,,,impossible,,,,,for,,,,,freq uency,,,,,measurement,,,,,and,,,,,carrier,,,,,tracking.,,,,,,,,,,The,,,,,paper,,,,,is,,,,,organize d,,,,,as,,,,,follows.,,,,,In,,,,,section,,,,,I,,,,,,the,,,,,frequency,,,,,hopping,,,,,pattern,,,,,sync hronization,,,,,module,,,,,in,,,,,the,,,,,DS/FHSS,,,,,TT&C,,,,,system,,,,,is,,,,,introduced., ,,,,In,,,,,section,,,,,II,,,,,,we,,,,,analyze,,,,,how,,,,,the,,,,,carrier,,,,,frequency,,,,,hopping,,, ,,influences,,,,,the,,,,,performance,,,,,of,,,,,the,,,,,carrier,,,,,tracking,,,,,loop.,,,,,In,,,,,sect ion,,,,,III,,,,,,a,,,,,carrier,,,,,tracking,,,,,loop,,,,,aided,,,,,by,,,,,frequency,,,,,hopping,,,,,pat tern,,,,,and,,,,,current,,,,,spacecraft,,,,,velocity,,,,,is,,,,,proposed.,,,,,In,,,,,section,,,,,IV,,,, ,,a,,,,,simulation,,,,,mode,,,,,on,,,,,the,,,,,ground,,,,,of,,,,,actual,,,,,requirement,,,,,of,,,,,T T&C,,,,,system,,,,,is,,,,,built,,,,,and,,,,,the,,,,,results,,,,,of,,,,,simulation,,,,,show,,,,,that,,, ,,this,,,,,method,,,,,is,,,,,very,,,,,simple,,,,,and,,,,,effective,,,,,for,,,,,DS/FHSS,,,,,TT&C,, ,,,system.,,,,,Finally,,,,,,some,,,,,conclusions,,,,,are,,,,,drawn,,,,,in,,,,,section,,,,,V.II．INPUT,,,,,SIGNAL,,,,,OF,,,,,CARRIER,,,,,TRACKING,,,,,LOOPAs,,,,,the,,,,,traditional,,,,,TT&C,,,,,and,,,,,communication,,,,,system,,,,,,the,,,,,inp ut,,,,,signal,,,,,of,,,,,carrier,,,,,tracking,,,,,loop,,,,,must,,,,,be,,,,,a,,,,,monotonous,,,,,inter mediate,,,,,frequency,,,,,signal,,,,,,so,,,,,the,,,,,received,,,,,RF,,,,,signal,,,,,should,,,,,be,,,, ,dehopped,,,,,by,,,,,the,,,,,frequency,,,,,hopping,,,,,patternsynchronization,,,,,module.,,,, ,In,,,,,FH,,,,,communication,,,,,system,,,,,,the,,,,,signal,,,,,during,,,,,a,,,,,hop,,,,,dwell,,,,, time,,,,,is,,,,,a,,,,,narrowband,,,,,signal,,,,,and,,,,,the,,,,,general,,,,,power,,,,,detector,,,,,is ,,,,,commonly,,,,,used,,,,,to,,,,,detect,,,,,the,,,,,frequency,,,,,hopping,,,,,signal,,,,,[2].,,,,,B ut,,,,,in,,,,,the,,,,,hybrid,,,,,DS/FHSS,,,,,TT&C,,,,,system,,,,,,the,,,,,signal,,,,,is,,,,,subme rged,,,,,in,,,,,the,,,,,noise,,,,,,it,,,,,is,,,,,impossible,,,,,to,,,,,acquire,,,,,signal,,,,,directly,,,,, by,,,,,power,,,,,detector,,,,,such,,,,,as,,,,,FH,,,,,communication,,,,,system.,,,,,However,,,, ,,the,,,,,signal,,,,,during,,,,,a,,,,,hop,,,,,dwell,,,,,time,,,,,in,,,,,the,,,,,system,,,,,just,,,,,is,,,,, a,,,,,direct,,,,,sequence,,,,,spread,,,,,spectrum,,,,,signal,,,,,,so,,,,,we,,,,,can,,,,,acquire,,,,,i t,,,,,based,,,,,on,,,,,the,,,,,acquisition,,,,,of,,,,,direct,,,,,sequence,,,,,spread,,,,,spectrum,,,, ,signal.,,,,,The,,,,,acquisition,,,,,methods,,,,,,such,,,,,as,,,,,serial-search,,,,,acquisition,,,,, ,parallel,,,,,acquisition,,,,,and,,,,,rapid,,,,,acquisition,,,,,based,,,,,on,,,,,FFT,,,,,have,,,,,be en,,,,,discussed,,,,,in,,,,,a,,,,,lot,,,,,of,,,,,papers,,,,,[3-5],,,,,,so,,,,,we,,,,,won’t,,,,,discuss,,, ,,the,,,,,problem,,,,,detailedly,,,,,in,,,,,this,,,,,paper.,,,,,In,,,,,our,,,,,system,,,,,,since,,,,,one,,,,,hop,,,,,dwell,,,,,time,,,,,is,,,,,very,,,,,short,,,,,,the,,,,,rapid,,,,,acquisition,,,,,based,,,,, on,,,,,FFT,,,,,which,,,,,can,,,,,extract,,,,,the,,,,,phase,,,,,delay,,,,,and,,,,,carrier,,,,,frequen cy,,,,,at,,,,,one,,,,,time,,,,,will,,,,,be,,,,,the,,,,,best,,,,,way,,,,,for,,,,,acquisition.,,,,,The,,,,,s cheme,,,,,of,,,,,the,,,,,frequency,,,,,hopping,,,,,patters,,,,,acquisition,,,,,,i.e.,,,,,,coarse,,,,, synchronization,,,,,,could,,,,,be,,,,,shown,,,,,as,,,,,Fig,,,,,1.Figure,,,,,1.,,,,,Scheme,,,,,of,,,,,frequency,,,,,hopping,,,,,pattern,,,,,synchronizationThe,,,,,synchronization,,,,,of,,,,,frequency,,,,,hopping,,,,,pattern,,,,,is,,,,,realized,,,,, by,,,,,the,,,,,local,,,,,frequency,,,,,synthesizer,,,,,rapid,,,,,searching,,,,,and,,,,,the,,,,,two,,, ,,dimension,,,,,rapid,,,,,acquisition,,,,,of,,,,,Direct,,,,,Sequence,,,,,PN,,,,,code,,,,,phase,,, ,,and,,,,,carrier,,,,,frequency.,,,,,At,,,,,the,,,,,beginning,,,,,,the,,,,,link,,,,,switch,,,,,is,,,,,o n,,,,,the,,,,,location,,,,,1,,,,,,and,,,,,the,,,,,output,,,,,signal,,,,,of,,,,,local,,,,,frequency,,,,,s ynthesizer,,,,,with,,,,,higher,,,,,hop,,,,,speed,,,,,than,,,,,the,,,,,received,,,,,one,,,,,is,,,,,mi xed,,,,,with,,,,,the,,,,,received,,,,,signal.,,,,,Then,,,,,,via,,,,,the,,,,,band,,,,,pass,,,,,filter,,,,, ,the,,,,,output,,,,,signal,,,,,of,,,,,mixer,,,,,is,,,,,fed,,,,,into,,,,,the,,,,,acquisition,,,,,module, ,,,,of,,,,,PN,,,,,code,,,,,and,,,,,carrier.,,,,,If,,,,,the,,,,,output,,,,,of,,,,,correlator,,,,,in,,,,,acq uisition,,,,,module,,,,,is,,,,,less,,,,,than,,,,,the,,,,,preset,,,,,threshold,,,,,,the,,,,,direct,,,,,se quence,,,,,spread,,,,,spectrum,,,,,signal,,,,,is,,,,,not,,,,,acquired,,,,,during,,,,,this,,,,,hop,,, ,,dwell,,,,,time,,,,,and,,,,,the,,,,,local,,,,,frequency,,,,,synthesizer,,,,,steps,,,,,the,,,,,next,,, ,,frequency.,,,,,By,,,,,contrast,,,,,,if,,,,,detection,,,,,variable,,,,,of,,,,,acquisition,,,,,modul e,,,,,is,,,,,more,,,,,than,,,,,the,,,,,preset,,,,,threshold,,,,,,it,,,,,means,,,,,that,,,,,the,,,,,freque ncy,,,,,hopping,,,,,signal,,,,,is,,,,,acquired,,,,,and,,,,,the,,,,,mixer,,,,,outputs,,,,,a,,,,,stable, ,,,,district,,,,,spread,,,,,spectrum,,,,,signal.,,,,,After,,,,,that,,,,,,the,,,,,switch,,,,,is,,,,,on,,,,, the,,,,,location,,,,,2,,,,,and,,,,,the,,,,,local,,,,,frequency,,,,,synthesizer,,,,,will,,,,,timely,,,,, change,,,,,the,,,,,output,,,,,frequency,,,,,according,,,,,to,,,,,the,,,,,frequency,,,,,hopping,,, ,,pattern.,,,,,After,,,,,the,,,,,coarse,,,,,synchronization,,,,,mentioned,,,,,above,,,,,,the,,,,,D S/FHSS,,,,,signal,,,,,have,,,,,being,,,,,dehopped,,,,,is,,,,,fed,,,,,to,,,,,PN,,,,,code,,,,,tracking,,,,,loop,,,,,and,,,,,a,,,,,fine,,,,,alignment,,,,,between,,,,,the,,,,,received,,,,,PN,,,,,code,,,,,and,,,,,local,,,,,PN,,,,,code,,,,,is,,,,,achieved,,,,,by ,,,,,a,,,,,code,,,,,tracking,,,,,loop,,,,,na mely ,,,,,the,,,,,delay-locked,,,,,loop.,,,,,Then,,,,,,the,,,,,output,,,,,of,,,,,code,,,,,tracking,,,,,loop,,,,,,i.e.,,,,,,a,,,,,duplicate,,,,,of,,,,,received,,,,,PN,,,,,code,,,,,,is,,,,,mixed,,,,,to,,,,,th e,,,,,IF,,,,,direct,,,,,sequence,,,,,spread,,,,,spectrum,,,,,signal,,,,,dehopped,,,,,by ,,,,,coarse ,,,,,synchronization,,,,,,and,,,,,a,,,,,monotonous,,,,,intermediate,,,,,frequency ,,,,,narrowb and,,,,,,,,,,signal,,,,,which,,,,,will,,,,,be,,,,,fed,,,,,to,,,,,carrier,,,,,tracking,,,,,loop,,,,,is,,,,,o btained.III.,,,,,CHARACTERISTIC,,,,,OF,,,,,DS/FHSS,,,,,CARRIER,,,,,TRA CKING,,,,,LOOPCompared,,,,,with,,,,,the,,,,,carrier,,,,,tracking,,,,,loop,,,,,in,,,,,ordinarycommunica tion,,,,,system,,,,,,because,,,,,of,,,,,the,,,,,high,,,,,dynamic,,,,,of,,,,,the,,,,,spacecraft,,,,,,e specially,,,,,during,,,,,the,,,,,landing,,,,,,accelerating,,,,,and,,,,,decelerating,,,,,,the,,,,,car rier,,,,,tracking,,,,,loop,,,,,of,,,,,hybrid,,,,,DS/FHSS,,,,,TT&C,,,,,system,,,,,will,,,,,be,,,,,i nfluenced,,,,,more,,,,,severely ,,,,,by,,,,,the,,,,,Doppler,,,,,Effect,,,,,(up,,,,,to,,,,,100KHz).,,,,,Addition,,,,,to,,,,,that,,,,,,a,,,,,Doppler,,,,,frequency ,,,,,agility ,,,,,resulted,,,,,from,,,,,th e,,,,,carrier,,,,,frequency ,,,,,hopping,,,,,won’t,,,,,be,,,,,eliminated,,,,,by ,,,,,dehopping,,,,,t he,,,,,frequency ,,,,,hopping,,,,,carrier,,,,,,and,,,,,which,,,,,becomes,,,,,the,,,,,main,,,,,fact or,,,,,influencing,,,,,the,,,,,performance,,,,,of,,,,,carrier,,,,,tracking,,,,,loop,,,,,in,,,,,DS/F HSS,,,,,TT&C,,,,,system.,,,,,The,,,,,frequency ,,,,,of,,,,,downlink,,,,,signal,,,,,of,,,,,DS/F HSS,,,,,TT&C,,,,,system,,,,,may ,,,,,be,,,,,described,,,,,as:)()(1)()()()(000i v i f c i f i f i f i f d +=+= where,,,,,i,,,,,is,,,,,the,,,,,sequence,,,,,number,,,,,of,,,,,carrier,,,,,frequency ,,,,,,)(0i f is,,,,,the,,,,,,,,,,ith,,,,,carrier,,,,,frequency ,,,,,,,,,,,)(i f d is,,,,,the,,,,,Doppler,,,,,frequency ,,,,,offset,,,,,during,,,,,the,,,,,,,,,,ith,,,,,hop,,,,,dwell,,,,,time,,,,,and,,,,,,,,,,)(i v ,,,,,is,,,,,the,,,,,current,,,,,speed,,,,,of,,,,,spacecraft.,,,,,We,,,,,can,,,,,assume,,,,,that,,,,,the,,,,,synchroniz ation,,,,,of,,,,,frequency ,,,,,hopping,,,,,pattern,,,,,has,,,,,been,,,,,completed,,,,,,and,,,,,the,,,,,output,,,,,frequency ,,,,,of,,,,,local,,,,,frequency ,,,,,synthesizer,,,,,is)()()(i f i f i f o lo ∆-=,,,,,,,,,,,where,,,,,)(i f ∆is,,,,,the,,,,,frequency ,,,,,difference,,,,,between,,,,,the,,,,,received,,,,,and,,,,,local,,,,,frequency ,,,,,,i.e.,,,,,,the,,,,,intermediate,,,,,freque ncy ,,,,,of,,,,,input,,,,,signal,,,,,of,,,,,carrier,,,,,tracking,,,,,loop.,,,,,Passing,,,,,a,,,,,IF,,,,,ba nd,,,,,pass,,,,,filter,,,,,,a,,,,,IF,,,,,signal,,,,,,the,,,,,frequency ,,,,,of,,,,,which,,,,,is,,,,,)(i f ∆,,,,,,is,,,,,obtained.,,,,,According,,,,,to,,,,,the,,,,,relation,,,,,among,,,,,the,,,,,velocity ,,,,,,carrier,,,,,frequen cy ,,,,,and,,,,,Doppler,,,,,frequency ,,,,,offset,,,,,,the,,,,,input,,,,,frequency ,,,,,of,,,,,carrier,,,,,tracking,,,,,loop,,,,,is,,,,,derived,,,,,easily,,,,,as,,,,,follow:,,,,,)()(1)()()()(0i v i f c i f i f i f i f d in +=+=∆∆ Then,,,,,,between,,,,,the,,,,,interval,,,,,of,,,,,the,,,,,,,,,,ith,,,,,frequency ,,,,,and,,,,,the,,,,,(i+i)th,,,,,frequency ,,,,,,the,,,,,Doppler,,,,,frequency ,,,,,agility ,,,,,)(i f d ∆,,,,,is,,,,,genera ted,,,,,,and,,,,,can,,,,,be,,,,,expressed,,,,,as:,,,,,)]()()1()1([1)(00i v i f i v i f c i f d -++=∆ Generally,,,,,speaking,,,,,,we,,,,,assume,,,,,that,,,,,the,,,,,velocity ,,,,,of,,,,,spacecraft ,,,,,during,,,,,two,,,,,adjacent,,,,,frequency ,,,,,won’t,,,,,change,,,,,,i.e.)()1(i v i v =+,,,,,,s o )()(1)(0i f i v ci f d ∆∆=,,,,,,which,,,,,shows,,,,,,,,,,that,,,,,the,,,,,frequency,,,,,agility,,,,,is,,,,,a,,,,,function,,,,,of,,,,,the,,,,,frequency ,,,,,difference,,,,,of,,,,,two,,,,,adjacent,,,,,hop,,,,,a nd,,,,,the,,,,,current,,,,,speed,,,,,of,,,,,spacecraft.,,,,,,,,,,Then,,,,,,the,,,,,input,,,,,signal,,,,,of,,,,,the,,,,,carrier,,,,,tracking,,,,,loop,,,,,can,,,,,be ,,,,,expressed,,,,,as:,,,,,,,,,, )(])()()(1222sin[)(2)(0t n nT t p n f n v c t f t f t R P t s n ab +++-++∙=∑∞∞→∆∆τσπππ where,,,,,P,,,,,is,,,,,the,,,,,carrier,,,,,power,,,,,after,,,,,the,,,,,synchronization,,,,,of,,,,,freq uency ,,,,,hopping,,,,,pattern,,,,,,)(t R ,,,,,is,,,,,the,,,,,modulated,,,,,data,,,,,,∆f ,,,,,is,,,,,the,,,,,intermediate,,,,,frequency ,,,,,,d f and,,,,,τ,,,,,are,,,,,the,,,,,rudimental,,,,,frequency ,,,,,o ffset,,,,,and,,,,,rudimental,,,,,phase,,,,,offset,,,,,brought,,,,,from,,,,,acquisition,,,,,module ,,,,,respective.,,,,,;1)(,10=≤≤t p t otherwise,,,,,0)(=t p ,,,,,,T,,,,,is,,,,,one,,,,,hop,,,,,dw ell,,,,,time,,,,,,σ,,,,,,,,,,is,,,,,the,,,,,timing,,,,,error,,,,,of,,,,,the,,,,,synchronization,,,,,of,,,,,f requency ,,,,,hopping,,,,,patterns,,,,,,n(t),,,,,is,,,,,the,,,,,additive,,,,,white,,,,,Gaussian,,,,,noise,,,,,with,,,,,two-side,,,,,power,,,,,spectral,,,,,density ,,,,,2N W/Hz,,,,,and,,,,,c,,,,,is,,,,,t he,,,,,velocity ,,,,,of,,,,,light.,,,,,The,,,,,tracking,,,,,resolution,,,,,is,,,,,the,,,,,basic,,,,,description,,,,,of,,,,,the,,,,,loop,,,,,performance,,,,,,and,,,,,we,,,,,can,,,,,obtain,,,,,it,,,,,by ,,,,,the,,,,,error,,,,,transfer,,,,,fun ction,,,,,as,,,,,follow:,,,,,where,,,,,,F(s),,,,,is,,,,,the,,,,,transfer,,,,,function,,,,,of,,,,,loop,,,,,filter,,,,,,K,,,,,is,,,,,the,,,,,gain,,,,,of,,,,,open,,,,,loop.,,,,,Then,,,,,we,,,,,can,,,,,apply,,,,,the,,,,,limit,,,,,theorem,,,,,,which,,,,,is,,,,,expressed,,,,,as,,,,,)()()(0100lim s H s s s Θ=∞→θ,to,,,,,derive,,,,,the,,,,,steady-state,,,,,tracking,,,,,error.,,,,,Unfortunately ,,,,,,the,,,,,derivation,,,,,of,,,,,Laplacian,,,,,transfer,,,,,of,,,,,,,,,,is,,,,,seen,,,,,to,,,,,be,,,,,impossible,,,,,,so,,,,,we,,,,,can’t,,,,,calcula te,,,,,the,,,,,measuring,,,,,error,,,,,precisely ,,,,,and,,,,,only,,,,,analyze,,,,,it,,,,,by ,,,,,simula tion.,,,,,For,,,,,the,,,,,2edorder,,,,,loop,,,,,,the,,,,,acquisition,,,,,time,,,,,can,,,,,be,,,,,expre ssed,,,,,as:3202nT ξωωρ∆= where,,,,,,0ω,,,,,is,,,,,the,,,,,initial,,,,,frequency ,,,,,offset,,,,,,n ω,,,,,and,,,,,ξ,,,,,are,,,,,the,,,,,natural,,,,,frequency ,,,,,and,,,,,damping,,,,,factor,,,,,of,,,,,the,,,,,tracking,,,,,loop.,,,,,In,,,,,the,,,,,hybrid,,,,,DS/FHSS,,,,,TT&C,,,,,system,,,,,,0ω,,,,,just,,,,,is,,,,,the,,,,,freque ncy ,,,,,agility ,,,,,which,,,,,is,,,,,a,,,,,function,,,,,of,,,,,time,,,,,according,,,,,to,,,,,the,,,,,fre quency ,,,,,hopping,,,,,pattern.,,,,,Thereby ,,,,,,three,,,,,cases,,,,,are,,,,,discussed.,,,,,Case,,,,,1:,,,,,Tp<Tc,,,,,,,,,,,i.e.,,,,,,hop,,,,,dwell,,,,,time,,,,,is,,,,,more,,,,,than,,,,,the,,,,,loop,,,,,acquisition,,,,,time.The,,,,,carrier,,,,,tracking,,,,,loop,,,,,is,,,,,able,,,,,to,,,,,acqu ire,,,,,and,,,,,track,,,,,the,,,,,DS/FHSS,,,,,TT&C,,,,,signal,,,,,,but,,,,,shift,,,,,the,,,,,unlock ,,,,,state,,,,,immediately ,,,,,when,,,,,the,,,,,next,,,,,frequency ,,,,,signal,,,,,is,,,,,fed,,,,,to,,,,,the,,,,,loop.,,,,,The,,,,,loop,,,,,steps,,,,,to,,,,,lock,,,,,,unlock,,,,,,re-lock,,,,,,re-unlock,,,,,s tate,,,,,repeatedly,,,,,for,,,,,all,,,,,time,,,,,,and,,,,,the,,,,,Doppler,,,,,offset,,,,,can’t,,,,,be,,,,,extracted,,,,,accurately .Case,,,,,2:,,,,,Tp>Tc,,,,,,i.e.,,,,,,hop,,,,,dwell,,,,,time,,,,,is,,,,,less,,,,,than,,,,,the,,,,,lo op,,,,,acquisition,,,,,time.,,,,,During,,,,,the,,,,,acquisition,,,,,state,,,,,of,,,,,loop,,,,,,the,,,,,f requency ,,,,,of,,,,,input,,,,,signal,,,,,is,,,,,likely ,,,,,to,,,,,step,,,,,up,,,,,suddenly ,,,,,,and,,,,,t hen,,,,,the,,,,,loop,,,,,steps,,,,,to,,,,,the,,,,,acquisition,,,,,state,,,,,once,,,,,again.,,,,,For,,,,,t he,,,,,case,,,,,,the,,,,,tracking,,,,,loop,,,,,will,,,,,step,,,,,to,,,,,acquisition,,,,,state,,,,,again,,,,,and,,,,,again,,,,,for,,,,,all,,,,,time.,,,,,,,,,,Case,,,,,3:,,,,,For,,,,,the,,,,,non-ideal,,,,,2ed,,,,,or,,,,,high-degree,,,,,order,,,,,loop,,,,,,the,,,,,acquisition,,,,,band,,,,,p ω∆,,,,,is,,,,,limited,,,,,,and,,,,,the,,,,,hopping,,,,,frequenc y ,,,,,agility,,,,,)(i f d ∆,,,,,also,,,,,influences,,,,,the,,,,,performance,,,,,of,,,,,loop.,,,,,When )(i f d ∆<p ω∆,,,,,,,,,,,the,,,,,conclusion,,,,,is,,,,,same,,,,,as,,,,,the,,,,,analysis,,,,,,,,,,mentio ned,,,,,above,,,,,,and,,,,,when )(i f d ∆>p ω∆,,,,,,,,,,,the,,,,,tracking,,,,,loop,,,,,won’t,,,,,loc ked,,,,,the,,,,,signal,,,,,forever.The,,,,,simulation,,,,,result,,,,,of,,,,,2ed,,,,,order,,,,,tracking,,,,,loop,,,,,used,,,,,com monly,,,,,in,,,,,TT&C,,,,,field,,,,,is,,,,,shown,,,,,in,,,,,Fig,,,,,2.,,,,,The,,,,,Doppler,,,,,agilit y ,,,,,is,,,,,plotted,,,,,by ,,,,,broken,,,,,line,,,,,and,,,,,the,,,,,time,,,,,response,,,,,is,,,,,denoted ,,,,,by ,,,,,real,,,,,line.,,,,,Fig.,,,,,2(a),,,,,shows,,,,,the,,,,,tracking,,,,,performance,,,,,witho ut,,,,,Doppler,,,,,offset,,,,,agility;,,,,,the,,,,,time,,,,,response,,,,,as,,,,,Tp<Tc,,,,,is,,,,,descr ibed,,,,,in,,,,,Fig.,,,,,2(b),,,,,,the,,,,,loop,,,,,state,,,,,is,,,,,alternating,,,,,between,,,,,locked,,,,,and,,,,,,,,,,unlocked.,,,,,In,,,,,Fig.,,,,,2(c),,,,,,the,,,,,loop,,,,,is,,,,,acquiring,,,,,signal,,,,,f orever.,,,,,Because,,,,,the,,,,,frequency ,,,,,is,,,,,changed,,,,,before,,,,,stepping,,,,,to,,,,,the ,,,,,locked,,,,,state,,,,,,the,,,,,loop,,,,,won’t,,,,,acquire,,,,,any ,,,,,signal,,,,,at,,,,,all,,,,,time.,,,,,In,,,,,Fig,,,,,2(d),,,,,,when )(i f d ∆>p ω∆,,,,,,the,,,,,tracking,,,,,capability ,,,,,of,,,,,the,,,,,loop,,,,,is,,,,,invalid,,,,,entirely .Figure,,,,,2.,,,,,Time,,,,,response,,,,,of,,,,,tracking,,,,,loop,,,,,with,,,,,Doppler,,,,,offset,,,,,agility:,,,,,,,,,,,,,,,(a) No,,,,,hopping,,,,,,(b),,,,,Tp<Tc,,,,,,,,,,,,,,,,(c),,,,,Tp>T c,,,,,,(d),,,,,)(i f d ∆>pω∆IV.,,,,,THE,,,,,SCHEME,,,,,OF,,,,,CARRIER,,,,,TRACKING,,,,,LOO P,,,,,AIDED,,,,,BY,,,,,HOPPING,,,,,PA TTERNThe,,,,,structure,,,,,of,,,,,the,,,,,carrier,,,,,track,,,,,loop,,,,,aided,,,,,by,,,,,the,,,,,hoppi ng,,,,,frequency,,,,,pattern,,,,,is,,,,,shown,,,,,in,,,,,Fig,,,,,3.,,,,,Generally,,,,,speaking,,,,,, we,,,,,can,,,,,assume,,,,,that,,,,,the,,,,,velocity,,,,,during,,,,,the,,,,,interval,,,,,time,,,,,betw een,,,,,two,,,,,adjacent,,,,,frequency,,,,,will,,,,,keep,,,,,a,,,,,fixed,,,,,value,,,,,,then,,,,,the,,,,,doppler,,,,,frequency,,,,,offset,,,,,,,,,,in,,,,,the,,,,,next,,,,,frequency,,,,,interval,,,,,c an,,,,,be,,,,,calculated,,,,,by,,,,,the,,,,,current,,,,,velocity,,,,,of,,,,,spacecraft,,,,,combined,,,,,with,,,,,carrier,,,,,frequency.,,,,,The,,,,,is,,,,,added,,,,,timely,,,,,to,,,,,the,,,,,adjust ment,,,,,value,,,,,of,,,,,the,,,,,carrier,,,,,NCO,,,,,when,,,,,the,,,,,new,,,,,frequency,,,,,signa l,,,,,is,,,,,fed,,,,,to,,,,,the,,,,,loop.,,,,,So,,,,,the,,,,,output,,,,,frequency,,,,,of,,,,,NCO,,,,,also ,,,,,changes,,,,,synchronal,,,,,as,,,,,the,,,,,frequency,,,,,changing,,,,,of,,,,,input,,,,,signal,,, ,,,and,,,,,the,,,,,loop,,,,,keeps,,,,,stable.,,,,,Deserve,,,,,to,,,,,mentioned,,,,,,before,,,,,the,,,, ,loop,,,,,stepped,,,,,to,,,,,steady,,,,,state,,,,,,the,,,,,spacecraft,,,,,velocity,,,,,used,,,,,by,,,,,t he,,,,,scheme,,,,,is,,,,,given,,,,,from,,,,,the,,,,,acquisition,,,,,module.,,,,,After,,,,,having,,, ,,being,,,,,locked,,,,,state,,,,,,then,,,,,the,,,,,velocity,,,,,should,,,,,be,,,,,extracted,,,,,from,, ,,,the,,,,,loop,,,,,itself,,,,,directly.,,,,,By,,,,,this,,,,,way,,,,,,the,,,,,loop,,,,,is,,,,,able,,,,,to,,,,, keep,,,,,stable,,,,,even,,,,,on,,,,,the,,,,,high,,,,,dynamic,,,,,condition.,,,,,Figure,,,,,3.,,,,,Carrier,,,,,tracking,,,,,loop,,,,,aided,,,,,by,,,,,frequency,,,,,hopping,,,,,patternBesides,,,,,the,,,,,thermal,,,,,noise,,,,,jitter,,,,,,the,,,,,main,,,,,error,,,,,of,,,,,carrier,,,, ,tracking,,,,,loop,,,,,aided,,,,,by,,,,,the,,,,,frequency,,,,,hopping,,,,,pattern,,,,,is,,,,,the,,,,,f requency,,,,,jitter,,,,,of,,,,,the,,,,,frequency,,,,,synthesizer,,,,,and,,,,,timing,,,,,error,,,,,due ,,,,,to,,,,,frequency,,,,,pattern,,,,,synchronization.,,,,,The,,,,,former,,,,,one,,,,,depends,,,,, on,,,,,the,,,,,resolution,,,,,of,,,,,frequency,,,,,synthesizer,,,,,as,,,,,other,,,,,communication,,,,,and,,,,,we,,,,,only,,,,,discuss,,,,,the,,,,,latter,,,,,one.,,,,,Briefly,,,,,,when,,,,,the,,,,,local, ,,,,frequency,,,,,changing,,,,,of,,,,,the,,,,,local,,,,,frequency,,,,,synthesizer,,,,,is,,,,,advanc ed,,,,,or,,,,,retarded,,,,,to,,,,,the,,,,,one,,,,,of,,,,,receive,,,,,signal,,,,,,the,,,,,aiding,,,,,modu le,,,,,will,,,,,provide,,,,,a,,,,,frequency,,,,,offset,,,,,to,,,,,the,,,,,carrier,,,,,NCO,,,,,at,,,,,the, ,,,,wrong,,,,,time,,,,,and,,,,,the,,,,,loop,,,,,will,,,,,step,,,,,to,,,,,the,,,,,unlocked,,,,,state,,,,, at,,,,,once,,,,,,i.e.,,,,,,response,,,,,of,,,,,frequency,,,,,step.,,,,,Fortunately,,,,,,when,,,,,the,, ,,,frequency,,,,,of,,,,,input,,,,,signal,,,,,changes,,,,,actually,,,,,,the,,,,,loop,,,,,will,,,,,retur n,,,,,to,,,,,the,,,,,steady,,,,,state,,,,,rapidly.,,,,,But,,,,,as,,,,,the,,,,,increase,,,,,of,,,,,synchro nization,,,,,error,,,,,,it,,,,,also,,,,,be,,,,,likely,,,,,to,,,,,become,,,,,too,,,,,severe,,,,,to,,,,,me et,,,,,the,,,,,resolution,,,,,requirement,,,,,of,,,,,the,,,,,TT&C,,,,,system.V.,,,,,SIMULA TIOMThe,,,,,model,,,,,of,,,,,carrier,,,,,tracking,,,,,loop,,,,,of,,,,,hybrid,,,,,DS/FHSS,,,,,sys tem,,,,,is,,,,,shown,,,,,in,,,,,Fig,,,,,3,,,,,,which,,,,,is,,,,,built,,,,,in,,,,,the,,,,,simulink,,,,,of,, ,,,Matlab.,,,,,The,,,,,tracking,,,,,loop,,,,,is,,,,,the,,,,,standard,,,,,costas,,,,,loop,,,,,commo nly,,,,,used,,,,,in,,,,,the,,,,,TT&C,,,,,field,,,,,,which,,,,,is,,,,,able,,,,,to,,,,,eliminate,,,,,the,, ,,,inference,,,,,resulted,,,,,form,,,,,the,,,,,polarity,,,,,change,,,,,of,,,,,the,,,,,modulated,,,,, data,,,,,[9].,,,,,To,,,,,adapt,,,,,the,,,,,Doppler,,,,,frequency,,,,,change,,,,,due,,,,,to,,,,,the,,,, ,spacecraft,,,,,movement,,,,,,the,,,,,loop,,,,,is,,,,,designed,,,,,as,,,,,a,,,,,2ed,,,,,order,,,,,loo p,,,,,,and,,,,,the,,,,,loop,,,,,filter,,,,,is,,,,,a,,,,,1st,,,,,order,,,,,filter.,,,,,The,,,,,simulation,,,,, parameter,,,,,is,,,,,set,,,,,according,,,,,to,,,,,the,,,,,actual,,,,,TT&C,,,,,task,,,,,as,,,,,follow s:,,,,,Carrier,,,,,frequency:,,,,,2.2GHz~2.3GHz,,,,,Amount,,,,,of,,,,,frequencies:,,,,,128,,,,,Frequency,,,,,hopping,,,,,pattern:,,,,,based,,,,,on,,,,,m-sequence,,,,,Rudimental,,,,,frequency,,,,,offset,,,,,after,,,,,acquisition:,,,,,300Hz,,,,,Intermediate,,,,,frequency,,,,,of,,,,,the,,,,,carrier,,,,,tracking,,,,,loop:,,,,,4.8MHz,,,,,Sampling,,,,,frequency:,,,,,16.3Mbps,,,,,Noise,,,,,Bandwidth,,,,,of,,,,,the,,,,,loop:,,,,,10Hz,,,,,A.,,,,,The,,,,,time,,,,,response,,,,,on,,,,,uniform,,,,,motion,,,,,and,,,,,,,,,,uniformly,,,, ,accelerated,,,,,motionWe,,,,,assume,,,,,the,,,,,spacecraft,,,,,speed,,,,,is,,,,,7.9km/s,,,,,,by,,,,,the,,,,,relation ,,,,,among,,,,,the,,,,,Doppler,,,,,frequency,,,,,,carrier,,,,,frequency,,,,,and,,,,,velocity,,,,,,t he,,,,,frequency,,,,,offset,,,,,of,,,,,the,,,,,input,,,,,IF,,,,,signal,,,,,of,,,,,loop,,,,,is,,,,,obtaine d,,,,,as,,,,,Fig,,,,,4(a).,,,,,The,,,,,max,,,,,frequency,,,,,agility,,,,,is,,,,,up,,,,,to,,,,,2.3KHz.,,, ,,The,,,,,time,,,,,response,,,,,without,,,,,aid,,,,,is,,,,,shown,,,,,in,,,,,the,,,,,Fig,,,,,4(b),,,,,an d,,,,,the,,,,,one,,,,,with,,,,,aid,,,,,by,,,,,hopping,,,,,pattern,,,,,is,,,,,shown,,,,,in,,,,,Fig4(c)., ,,,,The,,,,,results,,,,,show,,,,,that,,,,,the,,,,,loop,,,,,without,,,,,aid,,,,,is,,,,,unlocked,,,,,com pletely,,,,,,while,,,,,the,,,,,one,,,,,with,,,,,aid,,,,,can,,,,,track,,,,,the,,,,,carrier,,,,,accurately .,,,,,When,,,,,the,,,,,spacecraft,,,,,is,,,,,on,,,,,the,,,,,uniformly,,,,,accelerated,,,,,motion,,,,, (the,,,,,initial,,,,,speed,,,,,is,,,,,7.9km/s,,,,,,and,,,,,speed,,,,,accelerator,,,,,is,,,,,30g),,,,,,th e,,,,,time,,,,,response,,,,,is,,,,,shown,,,,,in,,,,,Fig,,,,,5.,,,,,The,,,,,same,,,,,conclusion,,,,,is, ,,,,obtained,,,,,as,,,,,pre-paragraph.,,,,,Figure,,,,,4.,,,,,,,,,,The,,,,,time,,,,,response,,,,,on,,,,,uniform,,,,,,,,,,,,,,,motion:,,,,,(a)doppler,,,,,frequency,(b)without,,,,,aid,,,,,,(c),,,,,with,,,,,aid.Figure,,,,,5.,,,,,Time,,,,,response,,,,,on,,,,,uniformly,,,,,accelerated,,,,,motion:(a)doppler,,,,,frequency,(b)without,,,,,aid,,,,,(c),,,,,with,,,,,aidB.,,,,,Tracking,,,,,resolution,,,,,on,,,,,different,,,,,hopping,,,,,speedIn,,,,,this,,,,,simulation,,,,,,the,,,,,resolution,,,,,of,,,,,carrier,,,,,tracking,,,,,loop,,,,,is, ,,,,obtained,,,,,by,,,,,calculating,,,,,variance.,,,,,The,,,,,relation,,,,,between,,,,,tracking,,,, ,resolution,,,,,and,,,,,hopping,,,,,speed,,,,,is,,,,,shown,,,,,in,,,,,Fig,,,,,6,,,,,on,,,,,different,, ,,,input,,,,,SNR,,,,,and,,,,,the,,,,,minimum,,,,,value,,,,,insuring,,,,,the,,,,,demodulating,,,, ,correctly,,,,,in,,,,,TT&C,,,,,system,,,,,is,,,,,13,,,,,dB.,,,,,The,,,,,result,,,,,of,,,,,simulation ,,,,,testified,,,,,that,,,,,the,,,,,resolution,,,,,is,,,,,not,,,,,sensitive,,,,,to,,,,,the,,,,,hopping,,,,, speed,,,,,and,,,,,the,,,,,scheme,,,,,is,,,,,very,,,,,robust,,,,,for,,,,,different,,,,,hopping,,,,,spe ed.Figure,,,,,6.,,,,,Stead-state,,,,,tracking,,,,,resolution,,,,,vs,,,,,hopping,,,,,speedC.,,,,,Tracking,,,,,resolution,,,,,on,,,,,different,,,,,timing,,,,,error,,,,,of,,,,,frequency, ,,,,,,,,,pattern,,,,,,,,,,synchronization,,,,,,,,,,For,,,,,carrier,,,,,tracking,,,,,loop,,,,,aided,,,,,by,,,,,the,,,,,frequency,,,,,hopping,,,,,p attern,,,,,,according,,,,,to,,,,,the,,,,,above,,,,,discussion,,,,,the,,,,,main,,,,,factor,,,,,impact ing,,,,,the,,,,,stability,,,,,of,,,,,loop,,,,,is,,,,,the,,,,,timing,,,,,error,,,,,caused,,,,,by,,,,,the,,,,, patterns,,,,,synchronization.,,,,,Fig,,,,,7,,,,,shows,,,,,the,,,,,stead-state,,,,,tracking,,,,,acc uracies,,,,,on,,,,,different,,,,,timing,,,,,error,,,,,of,,,,,synchronization,,,,,pattern,,,,,on,,,,,d ifferent,,,,,input,,,,,SNR.,,,,,The,,,,,measuring,,,,,error,,,,,is,,,,,increase,,,,,as,,,,,increasin g,,,,,of,,,,,timing,,,,,error,,,,,and,,,,,the,,,,,measurement,,,,,error,,,,,resulted,,,,,from,,,,,the ,,,,,SNR,,,,,even,,,,,can,,,,,be,,,,,ignored,,,,,when,,,,,the,,,,,time,,,,,error,,,,,is,,,,,up,,,,,to,,, ,,some,,,,,specified,,,,,value.,,,,,Consequently,,,,,,we,,,,,can,,,,,infer,,,,,that,,,,,the,,,,,trac k,,,,,accuracy,,,,,won’t,,,,,meet,,,,,the,,,,,requirement,,,,,of,,,,,TT&C,,,,,system,,,,,finally ,,,,,,and,,,,,the,,,,,problem,,,,,needs,,,,,to,,,,,be,,,,,researched,,,,,in,,,,,the,,,,,future.Figure,,,,,7.,,,,,Stead-state,,,,,tracking,,,,,resolution,,,,,vs,,,,,timing,,,,,error,,,,,of,,,,,,,,,,pattern,,,,,synchronization。

GSM移动通信系统综述——通信类外文文献翻译、中英文翻译

GSM移动通信系统综述GSM的历史在十九世纪八十年代，蜂窝电话系统在欧洲迅速发展起来，特别是在斯堪的纳维亚和联合国，还有法国和德国。

每个国家发展自己的系统，在设备和运营方面和别的其他国家不相同。

这是一个不受欢迎的情况，因为移动设备不仅受国界的限制，（这在统一的欧洲变的越来越不重要），而且还受每种设备类型的市场限制，以至于如此的经济规模和储蓄不能被实现。

欧洲首先认识到这种情况，在1982年欧洲邮电行政大会成立了一个欧洲移动特别小组，简称GSM，形成这个小组为了研究和发展欧洲的移动陆地通信系统，所提出的这个系统必须遵循以下几个标准；●好的话音质量。

●低的终端服务成本。

●支持国际漫游。

●支持手持终端。

●支持新的服务和设备。

●高效的光谱。

●ISDN兼容性。

在1989年，GSM的责任是被欧洲电讯学会标准所接受。

GSM规范的第一阶段于1990年被公布，商业服务在1991年被推行，到1993年，在22个国家有36个GSM网络。

虽然标准定型在欧洲，但GSM不只是欧洲的标准，超过200个GSM 网络（包括DCS1800和PCS1900）在世界上110个国家运营。

在1994年初，世界上有1.3百万个用户，到1997年10月已经超过了55百万个用户。

北美洲进入GSM领域比较晚，而且随之有一个GSM派生物叫PCS1900，GSM在每个大陆存在，而缩写词GSM代表了全球移动通信系统。

GSM 的发展选择了一个（在时间上）被分割的数字系统，相反的是，像美洲的AMPS和联合国TACS 一样标准的模拟的细胞系统。

他们相信那个处于压缩状态的算法和数字信号处理器的进展，允许实现原来的标准和在连续不断改进的系统方面的质量和费用。

超过八千页的GSM系统介绍尽量允许给中间供给者以灵活性和竞争性，但是足够的标准化保证在系统组成部分之间互相交织。

这个被通过为每个在系统中的定义的功能实体提供功能和交织描述。

GSM所提供的服务从开始，GSM的计划者想在提供的服务和信号使用的控制方面考虑ISDN 的兼容性。

通信工程外文文献

外文资料和中文翻译外文资料：Review of UMTS1.1 UMTS Network ArchitectureThe European/Japanese 3G standard is referred to as UMTS. UMTS is one of a number of standards ratified by the ITU-T under the umbrella of IMT-2000. It is currently the dominant standard, with the US CDMA2000 standard gaining ground, particularly with operators that have deployed cdmaOne as their 2G technology. At time of writing,Japan is the most advanced in terms of 3G network deployment. The three incumbent operators there have implemented three different technologies: J-Phone is using UMTS,KDDI has a CDMA2000 network, and the largest operator NTT DoCoMo is using a system branded as FOMA (Freedom of Multimedia Access). FOMA is based on the original UMTS proposal, prior to its harmonization and standardization.The UMTS standard is specified as a migration from the second generation GSM standard to UMTS via the General Packet Radio System (GPRS) and Enhanced Data for Global Evolution (EDGE), as shown in Figure. This is a sound rationale since as of April 2003, there were over 847 Million GSM subscribers worldwide1, accounting for68% of the global cellular subscriber figures. The emphasis is on keeping as much ofthe GSM network as possible to operate with the new system.We are now well on the road towards Third Generation (3G), where the network will support all traffic types: voice, video and data, and we should see an eventual explosion in the services available on the mobile device. The driving technology for this is the IP protocol. Many cellular operators are now at a position referred to as 2.5G, with the deployment of GPRS, which introduces an IP backbone into the mobile core network.The diagram below, Figure 2, shows an overview of the key components in a GPRS network, and how it fits into the existing GSM infrastructure.The interface between the SGSN and GGSN is known as the Gn interface and uses the GPRS tunneling protocol (GTP, discussed later). The primary reason for the introduction of this infrastructure is to offer connections to external packet networks, such as the Internet or a corporate Intranet.This brings the IP protocol into the network as a transport between the SGSN and GGSN. This allows data services such as email or web browsing on the mobile device,with users being charged based on volume of data rather than time connected.The dominant standard for delivery of 3G networks and services is the Universal Mobile Telecommunications System, or UMTS. The first deployment of UMTS is the Release ’99 architecture, shown below in Figure 3.In this network, the major change is in the radio access network (RAN) with the introduction of CDMA technology for the air interface, and ATM as a transport in the transmission part. These changes have been introduced principally to support the transport of voice, video and data services on the same network. The core network remains relatively unchanged, with primarily software upgrades. However, the IP protocol pushes further into the network with the RNC now communicating with the 3G SGSN using IP.The next evolution step is the Release 4 architecture, Figure 4. Here, the GSM core is replaced with an IP network infrastructure based around Voice over IP technology.The MSC evolves into two separate components: a Media Gateway (MGW) and an MSC Server (MSS). This essentially breaks apart the roles of connection and connection control. An MSS can handle multiple MGWs, making the network more scaleable.Since there are now a number of IP clouds in the 3G network, it makes sense to merge these together into one IP or IP/ATM backbone (it is likely both options will be available to operators.) This extends IP right across the whole network, all the way to the BTS.This is referred to as the All-IP network, or the Release 5 architecture, as shown in Figure 5. The HLR/VLR/EIR are generalised and referred to as the HLR Subsystem(HSS).Now the last remnants of traditional telecommunications switching are removed, leaving a network operating completely on the IP protocol, and generalised for the transport of many service types. Real-time services are supported through the introduction of a new network domain, the IP Multimedia Subsystem (IMS).Currently the 3GPP are working on Release 6, which purports to cover all aspects not addressed in frozen releases. Some call UMTS Release 6 4G and it includes such issues as interworking of hot spot radio access technologies such as wireless LAN.1.2 UMTS FDD and TDDLike any CDMA system, UMTS needs a wide frequency band in which to operate to effectively spread signals. The defining characteristic of the system is the chip rate, where a chip is the width of one symbol of the CDMA code. UMTS uses a chip rate of 3.84Mchips/s and this converts to a required spectrum carrier of 5MHz wide. Since this is wider than the 1.25MHz needed for the existing cdmaOne system, the UMTS air interface is termed ‘wideband’ CDMA.There are actually two radio technologies under the UMTS umbrella: UMTS FDD and TDD. FDD stands for Frequency Division Duplex, and like GSM, separates traffic in the uplink and downlink by placing them at different frequency channels. Therefore an operator must have a pair of frequencies allocated to allow them to run a network, hence the term ‘paired spectrum’. TDD or Time Division Duplex requires only one frequency channel, and uplink and downlink traffic are separated by sending them at different times. The ITU-T spectrum usage, as shown in Figure 6, for FDD is 1920- 980MHz for uplink traffic, and 2110-2170MHz for downlink. The minimum allocation an operator needs is two paired 5MHz channels, one for uplink and one for downlink, at a separation of 190MHz. However, to provide comprehensive coverage and services, it is recommended that an operator be given three channels. Considering the spectrum allocation, there are 12 paired channels available, and many countries have now completed the licencing process for this spectrum, allocating between two and four channels per licence. This has tended to work out a costly process for operators, since the regulatory authorities in some countries, notably in Europe, have auctioned these licences to the highest bidder. This has resulted in spectrum fees as high as tens of billions of dollars in some countries.The Time Division Duplex (TDD) system, which needs only one 5MHz band in which to operate, often referred to as unpaired spectrum. The differences between UMTS FDD and TDD are only evident at the lower layers, particularly on the radio interface. At higher layers, the bulk of the operation of the two systems is the same. As the name suggests, the TDD system separates uplink and downlink traffic by placing them in different time slots. As will be seen later, UMTS uses a 10ms frame structure which is divided into 15 equal timeslots. TDD can allocate these to be either uplink or downlink,with one or more breakpoints between the two in a frame defined. In this way, it is well suited to packet traffic, since this allows great flexibility in dynamically dimensioning for asymmetry in traffic flow.The TDD system should not really be considered as an independent network, but rather as a supplementfor an FDD system to provide hotspot coverage at higher data rates. It is rather unsuitable for large scale deployment due to interference between sites, since a BTS may be trying to detect a weak signal from a UE, which is blocked out by a relatively strong signal at the same frequency from a nearby BTS. TDD is ideal for indoor coverage over small areas.Since FDD is the main access technology being developed currently, the explanations presented here will focus purely on this system.1.3 UMTS Bearer ModelThe procedures of a mobile device connecting to a UMTS network can be split into two areas: the access stratum (AS) and the non-access stratum (NAS). The access stratum involves all the layers and subsystems that offer general services to the non-access stratum. In UMTS, the access stratum consists of all of the elements in the radio access network, including the underlying ATM transport network, and the various mechanisms such as those to provide reliable information exchange. All of the non-access stratum functions are those between the mobile device and the core network, for example, mobility management. Figure 7 shows the architecture model. The AS interacts with the NAS through the use of service access points (SAPs).UMTS radio access network (UTRAN) provides this separation of NAS and AS functions, and allows for AS functions to be fully controlled and implemented within the UTRAN. The two major UTRAN interfaces are the Uu, which is the interface between the mobile device, or User Equipment (UE) and the UTRAN, and the Iu, which is the interface between the UTRAN and the core network. Both of these interfaces can be divided into control and user planes each with appropriate protocol functions.A Bearer Service is a link between two points, which is defined by a certain set of characteristics. In the case of UMTS, the bearer service is delivered using radio access bearers.A Radio access bearer (RAB) is defined as the service that the access stratum (i.e.UTRAN) provides to the non-access stratum for transfer of user data between the User Equipment and Core Network. A RAB can consist of a number of subflows, which are data streams to the core network within the RAB that have different QoS characteristics,such as different reliabilities. A common example of this is different classes of bits with different bit error rates can be realised as different RAB subflows. RAB subflows are established and released at the time the RAB is established and released, and are delivered together over the same transport bearer.A Radio Link is defined as a logical association between a single User Equipment (UE) and a single UTRAN access point, such as an RNC. It is physically comprised of one or more radio bearers and should not be confused with radio access bearer.Looking within the UTRAN, the general architecture model is as shown in Figure 8 below. Now shown are the Node B or Base Station (BTS) and Radio Network Controller (RNC) components, and their respective internal interfaces. The UTRAN is subdivided into blocks referred to as Radio Network Subsystems (RNS), where each RNS consists of one controlling RNC (CRNC) and all the BTSs under its control. Unique to UMTS is the interface between RNSs, the Iur interface, which plays a key role in handover procedures. The interface between the BTS and RNC is the Iub interface.All the ‘I’ interfaces: Iu, Iur and Iub, currently3 use ATM as a transport layer. In the context of ATM, the BTS is seen as a host accessing an ATM network, within which the RNC is an ATM switch. Therefore, the Iub is a UNI interface, whereas the Iu and Iur interfaces are considered to be NNI, as illustrated in Figure 9.This distinction is because the BTS to RNC link is a point-to-point connection in that a BTS or RNC will only communicate with the RNC or BTS directly connected to it, and will not require communication beyond that element to another network element.For each user connection to the core network, there is only one RNC, which maintains the link between the UE and core network domain, as highlighted in Figure 10. This RNC is referred to as the serving RNC or SRNC. That SRNC plus the BTSs under its control is then referred to as the SRNS. This is a logical definition with reference to that UE only. In an RNS, the RNC that controls a BTS is known as the controlling RNC or CRNC. This is with reference to the BTS, cells under its control and all the common and shared channels within.As the UE moves, it may perform a soft or hard handover to another cell. In the case of a soft handover, the SRNC will activate the new connection to the new BTS. Should the new BTS be under the control of another RNC, the SRNC will also alert this new RNC to activate a connection along the Iur interface. The UE now has two links, one directly to the SRNC, and the second, through the new RNC along the Iur interface. In this case, this new RNC is logically referred to as a drift RNC or DRNC, see Figure 10. It is not involved in any processing of the call and merely relays it to the SRNC for connection to the core. In summary, SRNC and DRNC are usually associated with the UE and the CRNC is associated with the BTS. Since these are logical functions it is normal practice that a single RNC is capable of dealing with all these functions.A situation may arise where a UE is connected to a BTS for which the SRNC is not the CRNC for that BTS. In that situation, the network may invoke the Serving RNC Relocation procedure to move the core network connection. This process is described inSection 3.中文翻译：通用移动通信系统的回顾1.1 UMTS网络架构欧洲/日本的3G标准，被称为UMTS。

通信类英文原文及译文

ABSTRACTIn this paper, we present a system using an Android smartphone that collects, displays sensor data on the screen and streams to the central server simultaneously. Bluetooth and wireless Internet connections are used for data transmissions among the devices. Also, using Near Field Communication (NFC) technology, we have constructed a more efficient and convenient mechanism to achieve an automatic Bluetooth connection and application execution. This system is beneficial on body sensor networks (BSN) developed for medical healthcare applications. For demonstration purposes, an accelerometer, a temperature sensor and electrocardiography (ECG) signal data are used to perform the experiments. Raw sensor data are interpreted to either graphical or text notations to be presented on the smartphone and the central server. Furthermore, a Java-based central server application is used to demonstrate communication with the Android system for data storage and analysis.1INTRODUCTIONMobile communication devices are designed to achieve multiple purposes but mostly are focused on voice and short messaging services. Wireless technology has the benefit of improving data mobility, using different protocols such as Wi- Fi and Bluetooth. In the medical field, many studies introduced body sensor networks (BSN) for healthcare applications. BSN improves the patient’s monitoring system with the help of the modern technology. This can be done by various wearable sensors equipped with wireless capabilities, In addition, as seen in various researches, it is desirable to develop a low power system. Different types of sensors can be used for monitoring movements, temperature changes, heart-beat, blood pressure and more to establish a patient monitoring system. Bluetooth is one of the widely available options for managing wireless networks to simultaneously connect up to 7 ancillary devices.In this paper, we introduce a microcontroller system that communicates via Bluetooth with the smartphone for data collections, and streams data simultaneously to the central server for data storage and analysis via the Internet. This system provides a solution for mobile patients by forming a wireless BSN in Bluetooth and Wi-Fi/cellular Internet connections with a common Android smartphone which can monitor the patient status via wireless data transmission.2SYSTEM DESIGNFigure 1 represents the Mobile Sensor Data Collector that involves Bluetooth, Near Field Communication (NFC) and wireless Internet connections for collecting, streaming, storing and analyzing sensor data in real-time. Three different sensors transfer sampled data to the MSP430BT5190 which communicate with the CC2560 Bluetooth transmitter via UART and sends data to a smartphone using the Android and Bluetooth system. On the phone, it displays received data on the screen and streams to the server for storage and data analysis. The term “real-time” in this paper is used to express that data transfers are achieved without perceivable delays among the devices. Also, since the Android system is capable of running application software in the background mode, the application used in this paper has the ability to transfer data during a phone call.Figure 1Overall Design of Mobile Sensor Data CollectorA Java-based UDP server application is used to collect data sent from the smartphone via the Internet. When receiving data from the smartphone, the server application displays and saves all received data to a text file for later analysis. For experimental purposes, this server was implemented with an ordinary desktop to demonstrate our fundamental idea. Also, UDP protocol was chosen over TCP because UDP usually achieves faster transmission than the TCP protocol by not waiting for an acknowledgment signal back to the origin.3EXPERIMENT RESULTSAs shown in Figure 1, all experiments are initiated using an NFC tagging process to start the Android application and initiate the Bluetooth connection automatically. In this particular smartphone, the NFC tag reader is located on the backside. The user needs to tap on the NFC tag as shown in Figure 2 to run the program. The NFC tag containing theBluetooth MAC address of the CC2560 Bluetooth device is attached to demonstrate where the tag should be located.Figure 2Initiating connection processUp to 7 ancillary sensor nodes can be simultaneously connected to the Android system. However, a single sensor Bluetooth connection was employed for testing purposes.3.1Accelerometer Data CollectionIn this paper, the Android 2.3.3 and 4.0.3 operating systems are tested using Google Nexus S to display collected data and stream data to the server. The design of the new system is achieved first by collecting sensor data from the MSP430BT5190, transferred via the CC2560 Bluetooth transmitter. Then, the Bluetooth transmitter sends data to the smartphone, which displays the collected data in real-time. As an example, Figure 3(a) shows the accelerometer data collected and displayed on the smartphone in text and Figure 3(b) shows the data in the graphical notation.Figure 3Received real-time acceleration data display(a) text notation;(b) graphical notationThese data are being sent to the central server either via Wi-Fi or cellular networks for storage and analysis at the same time. Figure 4 shows the received data from the smartphone displayed on the server. The server also saves data to a text file in the designated directory for data analysis.Figure 4Received real-time acceleration data on server An axis value representation depends on the raw sensor data and this raw data could differ from the sensors. There are 3 axes provided from the sensor and each set of data needs to be interpreted. For this particular device used in this paper, x- axis data between -60 and -50 represents LEFT, between +50 and +60 represents RIGHT. This rule applies similarly to the other two axes. This differs from other sensors where the data output of acceleration is normally represented in terms of m/s2. However, a translation algorithm shares the same idea. Figure 5 is the result of translating the accelerometer data based on accelerometer movements.Figure5Accelerometer data translationThis type of the accelerometer translation was extended to the Snake Game sample provided by Android Developers [9]. The original game uses touch screen inputs to control the snake. The touch screen inputs were replaced by accelerometer movements to provide data in LEFT, RIGHT, UP and DOWN. The data analysis was done on the phone itself for test purposes. Figure 6 shows the movement of the snake on the phone that is controlled by accelerometer data from the MSP430 eZ430-RF2560.Figure 6Remote controlling Snake GameThis example emphasizes that accelerometer data can be adapted for the patientmovement detection system. Multiple accelerometers could be implemented to produce more advanced movement analysis.3.2Temperature Sensor Data CollectionA temperature sensor monitoring the real-time room temperature is used to perform the experiment. The procedure of the experiment resembles the previous section but with the different data interpretation. In this particular experiment, a heat gun was used to heat up or cool down the sensor for testing purposes as shown in Figure 7. Similar to the previous accelerometer application, Figure 8(a) shows the text notation of the received data in real-time and Figure 8(b) shows the graphical notation of the received data in real-time. Particularly in the graphical notation output, we provide a warning message if the temperature exceeds more than 35 degrees Celsius. Also, the graphical notation has a range of between 0 degrees Celsius to 50 degrees Celsius for this demonstration.Figure 9 shows the server displaying the received data from the smartphone. It delivers similar outputs compared to the accelerometer demonstration and also saves it to a text file.Figure 7Testing temperature sensor data transmissionFigure 8Received real-time temperature data display(a) text notation;(b) graphical notationFigure 9Received real-time temperature data on server3.3Electrocardiography (ECG) Data CollectionThe ECG signal is an important part of a patient monitoring system. Currently, ECG machines are dependent on wired connections which limit their data mobility. Our system using the Bluetooth protocol for ECG signal collections greatly enhances the mobility. This ECG signal is also sent simultaneously to the server via a wireless Internet connection through the smartphone in real-time. Figure 10 shows the display of received ECG signal on the smartphone and Figure 11 shows the same result transmitted to the server in the text format.Figure 10Received real-time ECG data in graphical notationFigure 11Received real-time ECG data on serverHeart-beat rate (BPM) can be determined after analysis of the data either on the smartphone or the server. In this particular example, it represents a patient’s stablecondition with a normal heart-beat rate at approximately 72 BPM. This type of data can be diagnostically valuable and easily transmitted for consultations with distant experts.3.4Overall Data Transmission Rate (DTR)The Data Transmission Rate (DTR) is another important part of the system considering the data size. In our system, DTR depends on the microcontroller, the Bluetooth transmitter and the wireless Internet connection speed. An UART connection between the sensor and microcontroller is established at the baud rate of 115200 bps which achieves a communication bandwidth up to 15KB/s. This emphasizes that our system is capable of the data transmission by integrating multiple types of sensors for a body sensor network system that can be important for patient monitoring, real-time data analysis and diagnosis.4CONCLUSIONSIn this paper, we introduced a system using the smartphone for collecting real-time sensor data and simultaneously streaming the data to the server using Bluetooth and Internet connections. This design is the advancement over ordinary wired sensor networks which are restricted to a fixed monitoring location. In the proposed system, an accelerometer, a temperature sensor and ECG signals have been selected for data transmission using Bluetooth and wireless Internet connections. Having the Bluetooth transmitter on the smartphone, the Android system receives and displays the data on the screen in the graphical or text format and streams the collected data to the central server for data analysis, diagnosis and archiving. Taking advantage of the Android system, NFC technology was used to reduce the unnecessary Bluetooth connection process. This system is highly scalable to include more sensors to produce an upgraded patient monitoring system that is both more accurate and responsive. Furthermore, storing history of collected sensor data in the central server is extremely critical for reliable patient diagnosis.摘要在本文中，我们提出了一个使用Android智能手机，收集传感器数据显示在屏幕上并同步到中央服务器的数据流同步系统。

通信工程外文文献翻译

毕业设计（论文）的外文文献翻译原始资料的题目/来源：Fundamentals of wireless communications by David Tse翻译后的中文题目：无线通信基础专业通信工程学生王晓宇学号110240318班号1102403指导教师杨洪娟翻译日期2015年6月15日外文文献的中文翻译7．mimo：空间多路复用与信道建模本书我们已经看到多天线在无线通信中的几种不同应用。

在第3章中，多天线用于提供分集增益，增益无线链路的可靠性，并同时研究了接受分解和发射分解，而且，接受天线还能提供功率增益。

在第5章中，我们看到了如果发射机已知信道，那么多采用多幅发射天线通过发射波束成形还可以提供功率增益。

在第6章中，多副发射天线用于生产信道波动，满足机会通信技术的需要，改方案可以解释为机会波束成形，同时也能够提供功率增益。

章以及接下来的几章将研究一种利用多天线的新方法。

我们将会看到在合适的信道衰落条件下，同时采用多幅发射天线和多幅接收天线可以提供用于通信的额外的空间维数并产生自由度增益，利用这些额外的自由度可以将若干数据流在空间上多路复用至MIMO信道中，从而带来容量的增加：采用n副发射天线和接受天线的这类MIMO 信道的容量正比于n。

过去一度认为在基站采用多幅天线的多址接入系统允许若干个用户同时与基站通信，多幅天线可以实现不同用户信号的空间隔离。

20世纪90年代中期，研究人员发现采用多幅发射天线和接收天线的点对点信道也会出现类似的效应，即使当发射天线相距不远时也是如此。

只要散射环境足够丰富，使得接受天线能够将来自不同发射天线的信号分离开，该结论就成立。

我们已经了解到了机会通信技术如何利用信道衰落，本章还会看到信道衰落对通信有益的另一例子。

将机会通信与MIMO技术提供的性能增益的本质进行比较和对比是非常的有远见的。

机会通信技术主要提供功率增益，改功率增益在功率受限系统的低信噪比情况下相当明显，但在宽带受限系统的高信噪比情况下则很不明显。

通信类英文文献及翻译

姓名：峻霖班级：通信143班学号：2014101108附录一、英文原文：Detecting Anomaly Trafﬁc using Flow Data in thereal VoIP networkI. INTRODUCTIONRecently, many SIP[3]/RTP[4]-based VoIP applications and services have appeared and their penetration ratio is gradually increasing due to the free or cheap call charge and the easy subscription method. Thus, some of the subscribers to the PSTN service tend to change their home telephone services to VoIP products. For example, companies in Korea such as LG Dacom, Samsung Net- works, and KT have begun to deploy SIP/RTP-based VoIP services. It is reported that more than ﬁve million users have subscribed the commercial VoIP services and 50% of all the users are joined in 2009 in Korea [1]. According to IDC, it is expected that the number of VoIP users in US will increase to 27 millions in 2009 [2]. Hence, as the VoIP service becomes popular, it is not surprising that a lot of VoIP anomaly trafﬁc has been already known [5]. So, Most commercial service such as VoIP services should provide essential security functions regarding privacy, authentication, integrity andnon-repudiation for preventing malicious trafﬁc. Particu- larly, most of current SIP/RTP-based VoIP services supply the minimal security function related with authentication. Though secure transport-layer protocols such as Transport Layer Security (TLS) [6] or Secure RTP (SRTP) [7] have been standardized, they have not been fully implemented and deployed in current VoIP applications because of the overheads of implementation and performance. Thus, un-encrypted VoIP packets could be easily sniffed and forged, especially in wireless LANs. In spite of authentication,the authentication keys such as MD5 in the SIP header could be maliciously exploited, because SIP is a text-based protocol and unencrypted SIP packets are easily decoded. Therefore, VoIP services are very vulnerable to attacks exploiting SIP and RTP. We aim at proposing a VoIP anomaly trafﬁc detection method using the ﬂow-based trafﬁc measurement archi-tecture. We consider three representative VoIP anomalies called CANCEL, BYE Denial of Service (DoS) and RTP ﬂooding attacks in this paper, because we found that malicious users in wireless LAN could easily perform these attacks in the real VoIP network. For monitoring VoIP packets, we employ the IETF IP Flow Information eXport (IPFIX) [9] standard that is based on NetFlow v9. This trafﬁc measurement method provides a ﬂexible and extensible template structure for various protocols, which is useful for observing SIP/RTP ﬂows [10]. In order to capture and export VoIP packets into IPFIX ﬂows, we deﬁne two additional IPFIX templates for SIP and RTP ﬂows. Furthermore, weadd four IPFIX ﬁelds to observe 802.11 packets which are necessary to detect VoIP source spooﬁng attacks in WLANs.II. RELATED WORK[8] proposed a ﬂooding detection method by the Hellinger Distance (HD) concept. In [8], they have pre- sented INVITE, SYN and RTP ﬂooding detection meth-ods. The HD is the difference value between a training data set and a testing data set. The training data set collected trafﬁc over n sampling period of duration Δ t.The testing data set collected trafﬁc next the training data set in the same period. If the HD is close to ‘1’, this testing data set is regarded as anomaly trafﬁc. For using this method, they assumed that initial training data set did not have any anomaly trafﬁc. Since this method was based on packet counts, it might not easily extended to detect other anomaly trafﬁc except ﬂooding. On the other hand, [11] has proposed a VoIP anomaly trafﬁc detection method using Extended Finite State Machine (EFSM). [11] has suggested INVITE ﬂooding, BYE DoS anomaly trafﬁc and media spamming detection methods. However, the state machine required more memory because it had to maintain each ﬂow. [13] has presented NetFlow-based VoIP anomaly detection methods for INVITE, REGIS-TER, RTP ﬂooding, and REGISTER/INVITE scan. How-ever, the VoIP DoS attacks considered in this paper were not considered. In [14], an IDS approach to detect SIP anomalies was developed, but only simulation results are presented. For monitoring VoIP trafﬁc, SIPFIX [10] has been proposed as an IPFIX extension. The key ideas of the SIPFIX are application-layer inspection andSDP analysis for carrying media session information. Yet, this paper presents only the possibility of applying SIPFIX to DoS anomaly trafﬁc detection and prevention. We described the preliminary idea of detecting VoIP anomaly trafﬁc in [15]. This paper elaborates BYE DoS anomaly trafﬁc and RTP ﬂooding anomaly trafﬁc detec-tion method based on IPFIX. Based on [15], we have considered SIP and RTP anomaly trafﬁc generated in wireless LAN. In this case, it is possible to generate the similiar anomaly trafﬁc with normal VoIP trafﬁc, because attackers can easily extract normal user information from unencrypted VoIP packets. In this paper, we have extended the idea with additional SIP detection methods using information of wireless LAN packets. Furthermore, we have shown the real experiment results at the commercial VoIP network.III. THE VOIP ANOMALY TRAFFIC DETECTION METHODA. CANCEL DoS Anomaly Trafﬁc DetectionAs the SIP INVITE message is not usually encrypted, attackers could extract ﬁelds necessary to reproduce the forged SIP CANCEL message by snifﬁng SIP INVITE packets, especially in wireless LANs. Thus, we cannot tell the difference between the normal SIP CANCEL message and the replicated one, because the faked CANCEL packet includes the normal ﬁelds inferred from the SIP INVITE message. The attacker will perform the SIP CANCEL DoS attack at the same wireless LAN, because the purpose of the SIP CANCEL attack is to prevent the normal call estab-lishment when a victim is waiting for calls. Therefore, as soonas the attacker catches a call invitation message for a victim, it will send a SIP CANCEL message, which makes the call establishment failed. We have generated faked SIP CANCEL message using sniffed a SIP INVITE message.Fields in SIP header of this CANCEL message is the same as normal SIP CANCEL message, because the attacker can obtain the SIP header ﬁeld from unencrypted normal SIP message in wireless LAN environment. Therefore it is impossible to detect the CANCEL DoS anomaly trafﬁc using SIP headers, we use the different values of the wireless LAN frame. That is, the sequence number in the 802.11 frame will tell the difference between a victim host and an attacker. We look into source MAC address and sequence number in the 802.11 MAC frame including a SIP CANCEL message as shown in Algorithm 1. We compare the source MAC address of SIP CANCEL packets with that of the previously saved SIP INVITE ﬂow. If the source MAC address of a SIP CANCEL ﬂow is changed, it will be highly probable that the CANCEL packet is generated by a unknown user. However, the source MAC address could be spoofed. Regarding 802.11 source spooﬁng detection, we employ the method in [12] that uses sequence numbers of 802.11 frames. We calculate the gap between n-th and (n-1)-th 802.11 frames. As the sequence number ﬁeld in a 802.11 MAC header uses 12 bits, it varies from 0 to 4095. When we ﬁnd that the sequence number gap between a single SIP ﬂow is greater than the threshold value of N that will be set from the experiments, we determine that the SIP host address as been spoofed for the anomaly trafﬁc.B. BYE DoS Anomaly Trafﬁc DetectionIn commercial VoIP applications, SIP BYE messages use the same authentication ﬁeld is included in the SIP IN-VITE message for security and accounting purposes. How-ever, attackers can reproduce BYE DoS packets through snifﬁng normal SIP INVITE packets in wireless LANs.The faked SIP BYE message is same with the normal SIP BYE. Therefore, it is difﬁcult to detect the BYE DoS anomaly trafﬁc using only SIP header information.After snifﬁng SIP INVITE message, the attacker at the same or different subnets could terminate the normal in- progress call, because it could succeed in generating a BYE message to the SIP proxy server. In the SIP BYE attack, it is difﬁcult to distinguish from the normal call termination procedure. That is, we apply the timestamp of RTP trafﬁc for detecting the SIP BYE attack. Generally, after normal call termination, the bi-directional RTP ﬂow is terminated in a bref space of time. However, if the call termination procedure is anomaly, we can observe that a directional RTP media ﬂow is still ongoing, whereas an attacked directional RTP ﬂow is broken. Therefore, in order to detect the SIP BYE attack, we decide that we watch a directional RTP ﬂow for a long time threshold of N sec after SIP BYE message. The threshold of N is also set from the experiments.Algorithm 2 explains the procedure to detect BYE DoS anomal trafﬁc using captured timestamp of the RTP packet. We maintain SIP session information between clients with INVITE and OK messages including the same Call-ID and 4-tuple (source/destination IP Address and port number) of the BYEpacket. We set a time threshold value by adding Nsec to the timestamp value of the BYE message. The reason why we use the captured timestamp is that a few RTP packets are observed under 0.5 second. If RTP trafﬁc is observed after the time threshold, this will be considered as a BYE DoS attack, because the VoIP session will be terminated with normal BYE messages. C. RTP Anomaly Trafﬁc Detection Algorithm 3 describes an RTP ﬂooding detection method that uses SSRC and sequence numbers of the RTP header. During a single RTP session, typically, the same SSRC value is maintained. If SSRC is changed, it is highly probable that anomaly has occurred. In addition, if there is a big sequence number gap between RTP packets, we determine that anomaly RTP trafﬁc has happened. As inspecting every sequence number for a packet is difﬁcult, we calculate the sequence number gap using the ﬁrst, last, maximum and minimum sequence numbers. In the RTP header, the sequence number ﬁeld uses 16 bits from 0 to 65535. When we observe a wide sequence number gap in our algorithm, we consider it as an RTP ﬂooding attack.IV. PERFORMANCE EVALUATIONA. Experiment EnvironmentIn order to detect VoIP anomaly trafﬁc, we established an experimental environment as ﬁgure 1. In this envi-ronment, we employed two VoIP phones with wireless LANs, one attacker, a wireless access router and an IPFIX ﬂow collector. For the realistic performance evaluation, we directly used one of the working VoIP networks deployed in Korea where an 11-digit telephone number (070-XXXX-XXXX) has been assigned to a SIP phone.With wireless SIP phones supporting 802.11, we could make calls to/from the PSTN or cellular phones. In the wireless access router, we used two wireless LAN cards- one is to support the AP service, and the other is to monitor 802.11 packets. Moreover, in order to observe VoIP packets in the wireless access router, we modiﬁed nProbe [16], that is an open IPFIX ﬂow generator, to create and export IPFIX ﬂows related with SIP, RTP, and 802.11 information. As the IPFIX collector, we have modiﬁed libipﬁx so that it could provide the IPFIX ﬂow decoding function for SIP, RTP, and 802.11 templates. We used MySQL for the ﬂow DB.B. Experimental ResultsIn order to evaluate our proposed algorithms, we gen-erated 1,946 VoIP calls with two commercial SIP phones and a VoIP anomaly trafﬁc generator. Table I shows our experimental results with precision, recall, and F-score that is the harmonic mean of precision and recall. In CANCEL DoS anomaly trafﬁc detection, our algorithm represented a few false negative cases, which was related with the gap threshold of the sequence number in 802.11 MAC header. The average of the F-score value for detecting the SIP CANCEL anomaly is 97.69%.For BYE anomaly tests, we generated 755 BYE mes-sages including 118 BYE DoS anomalies in the exper-iment. The proposed BYE DoS anomaly trafﬁc detec-tion algorithm found 112 anomalies with the F-score of 96.13%. If an RTP ﬂow is terminated before the threshold, we regard the anomaly ﬂow as a normal one. In this algorithm, we extract RTP session information from INVITE and OK or session description messages using the same Call-ID of BYE message. It is possible not to capture those packet, resulting in a few false-negative cases. The RTP ﬂooding anomaly trafﬁc detection experiment for 810 RTP sessions resulted in the F score of 98%.The reason of false-positive cases was related with the sequence number in RTP header. If the sequence number of anomaly trafﬁc is overlapped with the range of the normal trafﬁc, our algorithm will consider it as normal trafﬁc.V. CONCLUSIONSWe have proposed a ﬂow-based anomaly trafﬁc detec-tion method against SIP and RTP-based anomaly trafﬁc in this paper. We presented VoIP anomaly trafﬁc detection methods with ﬂow data on the wireless access router. We used the IETF IPFIX standard to monitor SIP/RTP ﬂows passing through wireless access routers, because its template architecture is easily extensible to several protocols. For this purpose, we deﬁned two new IPFIX templates for SIP and RTP trafﬁc and four new IPFIX ﬁelds for 802.11 trafﬁc. Using these IPFIX ﬂow templates,we proposed CANCEL/BYE DoS and RTP ﬂooding trafﬁc detection algorithms. From experimental results on the working VoIP network in Korea, we showed that our method is able to detect three representative VoIP attacks on SIP phones. In CANCEL/BYE DoS anomaly trafﬁcdetection method, we employed threshold values about time and sequence number gap for classﬁcation of normal and abnormal VoIP packets. This paper has not been mentioned the test result about suitable threshold values. For the future work, we will show the experimental result about evaluation of the threshold values for our detection method.二、英文翻译：交通流数据检测异常在真实的世界中使用的VoIP网络一 .介绍最近,多SIP[3],[4]基于服务器的VoIP应用和服务出现了,并逐渐增加他们的穿透比及由于自由和廉价的通话费且极易订阅的法。

通信工程专业外语 unit13原文与翻译

Unit 13Comparison between GSM and CDMA GSM与CDMA之比较Using CDMA/FDD technology, subscribers of CDMA cellular mobile communication system can transmit their information simultaneously through the same channel. On the other hand, the GSM system adopts TDMA/FDD method to transmit and distinguish information from different GSM mobile stations. In addition, in favor of QCELP arithmetic, RAKE receiver, power control and soft switching etc., CDMA shows more advantages in its system performance than the GSM, such as greater anti-interference capability, bigger system capacity, higher successful connection ratio, fewer off-line chances, low probability of intercept(LPI), and so on.使用码分多址/频分双工技术，用户的蜂窝移动通信系统的传输信息的同时，通过同样的渠道。

另一方面，该系统采用时分多址/频分双工传输的方法和识别信息从不同的移动台。

此外，有利于中国电信集团广州研发中心算术，耙式接收器，功率控制和软开关等，显示出更多的优势在码分多址系统性能比，如更高的抗干扰能力，更大的系统容量，连接成功率较高，离线的机会少，低截获概率（低截获概率），等。

5G无线通信网络中英文对照外文翻译文献

5 G 无线通信网络中英文对照外文翻译文献(文档含英文原文和中文翻译 )翻译：5G 无线通信网络的蜂窝结构和关键技术摘要第四代无线通信系统已经或者即将在许多国家部署。

然而，随着无线移动设备和服务的激增，仍然有一些挑战尤其是4G 所不能容纳的，例如像频谱危机和高能量消耗。

无线系统设计师们面临着满足新型无线应用对高数据速率和机动性要求的持续性增长的需求，因此他们已经开始研究被期望于 2020 年后就能部署的第五代无线系统。

在这篇文章里面，我们提出一个有内门和外门情景之分的潜在的蜂窝结构，并且讨论了多种可行性关于5G 无线通信系统的技术，比如大量的MIMO 技术，节能通信，认知的广播网络和可见光通信。

面临潜在技术的未知挑战也被讨论了。

介绍信息通信技术（ICT）创新合理的使用对世界经济的提高变得越来越重要。

无线通信网络在全球 ICT 战略中也许是最挑剔的元素，并且支撑着很多其他的行业，它是世界上成长最快最有活力的行业之一。

欧洲移动天文台（EMO）报道2010 年移动通信业总计税收1740 亿欧元,从而超过了航空航天业和制药业。

无线技术的发展大大提高了人们在商业运作和社交功能方面通信和生活的能力无线移动通信的显著成就表现在技术创新的快速步伐。

从 1991 年二代移动通信系统(2G)的初次登场到 2001 年三代系统（3G）的首次起飞，无线移动网络已经实现了从一个纯粹的技术系统到一个能承载大量多媒体内容网络的转变。

4G 无线系统被设计出来用来满足 IMT-A 技术使用 IP 面向所有服务的需求。

在 4G 系统中，先进的无线接口被用于正交频分复用技术（OFDM ），多输入多输出系统（MIMO）和链路自适应技术。

4G 无线网络可支持数据速率可达 1Gb/s 的低流度，比如流动局域无线访问，还有速率高达 100M /s 的高流速，例如像移动访问。

LTE 系统和它的延伸系统 LTE-A，作为实用的 4G 系统已经在全球于最近期或不久的将来部署。

通信工程移动通信中英文对照外文翻译文献

中英文翻译(文档含英文原文和中文翻译)附件1：外文资料翻译译文通用移动通信系统的回顾1.1 UMTS网络架构欧洲/日本的3G标准，被称为UMTS。

UMTS是一个在IMT-2000保护伞下的ITU-T 批准的许多标准之一。

随着美国的CDMA2000标准的发展，它是目前占主导地位的标准，特别是运营商将cdmaOne部署为他们的2G技术。

在写这本书时，日本是在3G 网络部署方面最先进的。

三名现任运营商已经实施了三个不同的技术：J - PHONE 使用UMTS，KDDI拥有CDMA2000网络，最大的运营商NTT DoCoMo正在使用品牌的FOMA（自由多媒体接入）系统。

FOMA是基于原来的UMTS协议，而且更加的协调和标准化。

UMTS标准被定义为一个通过通用分组无线系统（GPRS）和全球演进的增强数据技术（EDGE）从第二代GSM标准到UNTS的迁移，如图。

这是一个广泛应用的基本原理，因为自2003年4月起，全球有超过847万GSM用户，占全球的移动用户数字的68％。

重点是在保持尽可能多的GSM网络与新系统的操作。

我们现在在第三代（3G）的发展道路上，其中网络将支持所有类型的流量：语音，视频和数据，我们应该看到一个最终的爆炸在移动设备上的可用服务。

此驱动技术是IP协议。

现在，许多移动运营商在简称为2.5G的位置，伴随GPRS的部署，即将IP骨干网引入到移动核心网。

在下图中，图2显示了一个在GPRS网络中的关键部件的概述，以及它是如何适应现有的GSM基础设施。

SGSN和GGSN之间的接口被称为Gn接口和使用GPRS隧道协议（GTP的，稍后讨论）。

引进这种基础设施的首要原因是提供连接到外部分组网络如，Internet或企业Intranet。

这使IP协议作为SGSN和GGSN之间的运输工具应用到网络。

这使得数据服务，如移动设备上的电子邮件或浏览网页，用户被起诉基于数据流量，而不是时间连接基础上的数据量。

通信工程外文翻译文献

中英文对照外文翻译文献(文档含英文原文和中文翻译)计算机网络冗余GPS时间同步电路板的设计与实现摘要：如今，在计算机网络系统中准确和可靠的时间是一个基本要求。

为实现这一必要性，时间同步想法产生了。

同时在某些情况下，可靠的时间是如此的重要，以致于一个冗余的结构得以应用。

在本文中，时间同步系统的主要研究是设计和实施一个时间同步电路，该电路能够通过NTP协议与计算机网络同步时间。

在本设计中还嵌入了冗余方案以便提供更高的可靠性。

关键字：计算机网络GPS时间NTP 冗余时间同步时间同步协议时间服务器1. 引言我们通常会把电脑的时间和手表的误差设置在一两分钟内，但另一方面，准确和可靠的时间对于财务和法律事务、运输、分销系统，和许多其他涉及资源分布广泛的应用程序是必要的。

举一个例子说明，在一个分布式的机票预订系统，如果分布式计算机时间不同，座椅可以卖出两倍价格甚至更多，或者在网上股票交易完成之前会产生法律后果。

在这方面，世界协调时和时钟同步已开发出来。

基础的时间尺度已随着历史得到改进，以地球自转为基础的地球时和原子时也产生了。

一些重要的时间尺度还包括国际原子时（TAI）、通用协调时间尺度（UTC）、和标准时间或民用时间。

时钟同步协议的想法是，即使最初设置准确，但电脑的内部时钟也可能与世界时钟不同。

之后，由于时钟漂移，会有相当大的误差，所以总是有必要将这些漂移的时钟同步到参考时钟源。

时间同步源包括地球上的无线电同步技术（WWV, WWVH, WWVB, DCF77 and LORAN-C）、卫星时间同步技术（GOES, GPS, GLONASS, and Galileo）、互联网时间同步技术以及电话拨号时间同步技术。

在这些时钟源中，全球定位系统（GPS）提供了一些特殊的优点，如时间精度、抗噪声干扰、在世界各地都可用、并不断引用国际标准。

如今，相比其他时钟资源，全球定位系统时钟的使用更为广泛。

图1显示了一个典型的时间同步结构，其中时间服务器从GPS接收的数据作为时间同步源。

通信工程类外文翻译、中英文翻译、外文文献翻译

宽带，稳定增益，FET输入的运算放大器特征：●400MHz稳态增益带宽●低输入偏置电流:5pA●高输入电阻:1012Ω或1.0pF●极低的dG/dP :0.006%/0.009°●低扭曲:在5MHz为90dB●快速设置：17ns(0.01%)●高输出电流：60mA●超速传动快速恢复应运：●宽带光电二极管放大器●峰值检测●CCD输出缓冲器●ADC输入缓冲器●高速积分仪●检测和测量前端宽带光电二极管转移阻抗放大器一种包含宽带，稳态增益，电压反馈运算OPA655，当有FET输入时，能为ADC 缓冲器和转移阻抗设备提供十分宽广的动态放大范围。

良好的脉冲设置和极低的调和扭曲将支持更高要求的ADC输入缓冲需要。

宽带稳态增益和FET输入在高速，低噪声积分器中允许特殊的操作。

由FET输入所提供的高输入阻抗和低偏置电流能被极低的输入电压噪声支持，在宽带光电二极管设备中达到极低的积分噪声。

给定的OPA655高达240MHZ的增益带宽产品可以提供高宽带转移阻抗。

如下图所示，来自于47PF 的电容高达1兆欧的转移阻抗可以提供1MHZ，-3增益的带宽。

性能讨论：使用FET输入阻抗的放大器具有同那些用biploar阻抗相似的功能外，还有一些重要的优点。

在标准运算中，低输入偏置电流可以减少由于一个非常高或者未知源的阻抗所产生的直流电压错误。

在绝大多数OPA655使用中，输出直流错误只是由于低于1mv输入激励电压所造成的。

类似地，输入电流噪声几乎对输出电流噪声影响很小。

对于低电流噪声和低于6nv/ 输入电压噪声的OPA655对于宽带阻抗的应用极为有益。

OPA655的高宽带增益和近乎线性的输出，可以通过5MHz对于2v的峰值电压摆动在100Ω处，来控制调和扭曲低于-90dbc.在低频率或高负载阻抗时，这种显著地减少扭曲可以被观察到。

图1 放大器的内部原理操作时需考虑的问题对于PC板外形的仔细观察可以实现如典型性能曲线中所示的特殊操作。

中英论文翻译-对照全球移动通信系统本科学位论文

GSM（Global System for Mobile Communication）The success of mobile systems across the world is a sign that communication is moving towards a more personalized, convenient system. People who have to use a mobile phone on business soon begin to realize that the ability to phone any time, any place in one's personal life rapidly becomes a necessity, not a convenience.The speed and rapidity with which the personal communications revolution takes place is, unlike fixed transmission systems, highly dependent on technology and communication standards.For mobile the three key elements to achieving service take-up are the cost, the size and the weight of the phone, and the cost and quality of the link.3 If any of these are wrong, especially the first two, then market growth is liable to be severely restricted. The fixed telephone service is global and the interconnection varies from coaxial cable to optical fibre and satellite.The national standards are different, but with common interfaces and interface conversion, interconnection can take place. For mobile the problem is far more complex, with the need to roam creating a need for complex networks and systems. Thus in mobile the question of standards is far more crucial to success than fixed systems. 4 In addition, there is also the vexed question of spectrum allocation in the mobile area.Mobile systems originally operated in analog mode in the 450 MHz band, moving later to 900 MHz with digital GSM and then to 1,800 MHz with personal communication systems. The history of mobility can split into generations. The first generation systems were the advanced mobile phone systems (AMPS) in the US, total access communication system (TACS) in most of Europe and Nordic mobile telephone system (NMT); which were all analogue systems. The second generation is vary much dominated by the standard first set out in Europe by the group special mobile (GSM) committee, which was designed as a global mobile communication system.The GSM system is based on a cellular communications principle which wasfirst proposed as a concept in the 1940s by Bell System engineers in the US. The idea came out of the need to increase network capacity and got round the fact that broadcast mobile networks, operating in densely populated areas, could be jammed by a very small number of simultaneous calls. 5 The power of the cellular system was that it allowed frequency reuse.The cellular concept is defined by two features, frequency reuse and cell splitting. Frequency reuse comes into play by using radio channels on the same frequency in coverage areas that are far enough apart not to cause co-channel interference. This allows handling of simultaneous calls that exceed the theoretical spectral capacity. Cell splitting is necessary when the traffic demand on a cell has reached the maximum and the cell is then divided into a micro-cellular system. The shape of cell in a cellular system is always depicted as a hexagon and the cluster size can be seven, nine or twelve.The GSM system requires a number of functions to be created for a fully operational mobile system.The cell coverage area is controlled by a base station which is itself made up of two elements. The first element is the transmission system which communicates out to the mobile and also receives information from it to set up and maintain calls when actually in operation. The base station transceiver (BST) is controlled by the base station controller (BSC), which communicates with the mobile switching center (MSC) ---- the essential link to the local public switched telephone network (PSTN), and to the subscriber data which is stored in registers within the system. The subscriber registers allow the GSM system to check a subscriber who requests the use of the network, allow access and then set up the charging function, etc. 6 The GSM system was allocated part of the 900 MHz band at the 1978 World Administration Conference (WAC), the actual bands being 890 to 915 MHz for the uplink transmission and 935 to 960 MHz for the downlink. The access method is time division multiple access (TDMA).The GSM system operates in a burst transmission mode with 124 radio channels in the 900 MHz band, and these bursts can carry different types of information. Thefirst type of information is speech, which is coded at 6.5 kbit/s or 13 kbit/s. The second type is data, which can be sent at 3.6 kbit/s, 6 kbit/s or 12.6kbit/s. These two forms of transmission are the useful parts of the transmission, but have to be supported by overhead information which is sent in control channels (CCH).The use of digital radio transmission and the advanced handover algorithms between radio cells in GSM network allows for significantly better frequency usage than in analogue cellular systems, thus increasing the number of subscribers that can be served. 7 Since8 GSM provides common standard, cellular subscribers will also be able to use their telephones over the entire GSM service area. Roaming is fully automatic between and within all countries covered by GSM system. In addition to international roaming, GSM provides new services, such as high-speed data communication, Facsimile and short message service. The GSM technical specifications are designed to work in concert with other standards, e. g. ISDN. Interworking between the standards is in this way assured. In the long term perspective cellular systems, using a digital technology, will become the universal method of telecommunication.The third generation mobile communication system currently being developed9 in Europe is intended to integrate all the different services of second generation systems and cover a much wider range of broadband services (voice, data, video and multimedia) consistent and compatible with technology developments taking place within the fixed telecommunication networks.全球移动通信系统世界范围移动通信的成功标志着通信正在向着更加个人化、更加方便的通信系统迈进。

通信专业的外文及外文翻译

Research on Carrier Tracking in Hybrid DS/FHSpread Spectrum TT&C SystemAbstractBecause of the effect of carrier frequency hopping, the input IF signal of carrier tracking loop in DS/FHSS (Direct Sequence/Frequency Hopping Spread Spectrum) TT&C (Telemetry, Tracking & Command) System is characterized by the Doppler frequency agile. The tracking loop will shift to the frequency step response state ceaselessly and the measurement resolution severely decline, even the loop is likely to be unlocked. This paper presents a carrier tracking loop aided by frequency hopping pattern. In order to keep the stability of the tracking loop, the Doppler frequency agility in the next frequency hopping dwell is estimated and timely compensated to the frequency adjustment of carrier NCO according to the preset frequency hopping pattern and current spacecraft velocity. Simulation results show that this method effectively eliminates the instability due to carrier frequency hopping, and the resolution of loop meets the requirement of TT&C system.Keywords：carrier tracking；DS/FHSS；frequency agility；aided；TT&CI．INTRODUCTIONThe main function of TT&C (Telemetry, Tracking and Command) system is ranging and velocity measurement. Presently, the most common used TT&C systems are unit carrier system and unit spread spectrum system. For the unit carrier TT&C system, ranging is realized by measuring the phase difference between transmitted and received tones, and for the unit spread spectrum TT&C system, according to the autocorrelation properties of PN code, ranging is realized by measuring the phase delay between the received and local pseudonoise (PN) code. Velocity measurement in both of TT&C systems depends on extracting the frequency difference resulting from the Doppler phenomena between the transmitted and received carrier. While all the processes mentioned above are finished on the ground of high resolution carrier tracking, and the phase lock loop is the common used method to implement it in TT&C system. As the space electromagnetism environment become more and more complicated, the capability of anti-jamming is required by the future TT&C system [1]. So we consider using the hybrid DS/FHSS (Direct Sequence/Frequency Hopping Spread Spectrum) technology to build a more robust TT&C system.For many ordinary hybrid DS/FHSS communication systems, the most important function is demodulating data but not measuring, so it is not necessary to measure the carrier frequency precisely. However, in hybrid DS/FHSS TT&C system, measuring and tracking the carrier precisely is the foundation of system, so some special problem needs to be solved. In the hybrid DS/FHSS TT&C system, even the received signal has been dehopped by the pattern synchronization module, due to the Doppler Effect and carrier frequency hopping, the input frequency of tracking loop contains frequency agility severely. As a result, the loop is likely to shift to the frequency step responses state again and again, and it seems to be impossible for frequency measurement and carrier tracking. The paper is organized as follows. In section I, the frequency hopping pattern synchronization module in the DS/FHSS TT&C system is introduced. In section II, we analyze how the carrier frequency hopping influences the performance of the carrier tracking loop. In section III, a carrier tracking loop aided by frequency hopping pattern and current spacecraft velocity is proposed. In section IV, a simulation mode on the ground of actual requirement of TT&C system is built and the results of simulation show that this method is very simple and effectivefor DS/FHSS TT&C system. Finally, some conclusions are drawn in section V.II．INPUT SIGNAL OF CARRIER TRACKING LOOPAs the traditional TT&C and communication system, the input signal of carrier tracking loop must be a monotonous intermediate frequency signal, so the received RF signal should be dehopped by the frequency hopping patternsynchronization module. In FH communication system, the signal during a hop dwell time is a narrowband signal and the general power detector is commonly used to detect the frequency hopping signal [2]. But in the hybrid DS/FHSS TT&C system, the signal is submerged in the noise, it is impossible to acquire signal directly by power detector such as FH communication system. However, the signal during a hop dwell time in the system just is a direct sequence spread spectrum signal, so we can acquire it based on the acquisition of direct sequence spread spectrum signal. The acquisition methods, such as serial-search acquisition, parallel acquisition and rapid acquisition based on FFT have been discussed in a lot of papers [3-5], so we won’t discuss the problem detailedly in this paper. In our system, since one hop dwell time is very short, the rapid acquisition based on FFT which can extract the phase delay and carrier frequency at one time will be the best way for acquisition. The scheme of the frequency hopping patters acquisition, i.e., coarse synchronization, could be shown as Fig 1.Figure 1. Scheme of frequency hopping pattern synchronization The synchronization of frequency hopping pattern is realized by the local frequency synthesizer rapid searching and the two dimension rapid acquisition of Direct Sequence PN code phase and carrier frequency. At the beginning, the link switch is on the location 1, and the output signal of local frequency synthesizer with higher hop speed than the received one is mixed with the received signal. Then, via the band pass filter, the output signal of mixer is fed into the acquisition module of PNcode and carrier. If the output of correlator in acquisition module is less than the preset threshold, the direct sequence spread spectrum signal is not acquired during this hop dwell time and the local frequency synthesizer steps the next frequency. By contrast, if detection variable of acquisition module is more than the preset threshold, it means that the frequency hopping signal is acquired and the mixer outputs a stable district spread spectrum signal. After that, the switch is on the location 2 and the local frequency synthesizer will timely change the output frequency according to the frequency hopping pattern. After the coarse synchronization mentioned above, the DS/FHSS signal have being dehopped is fed to PN code tracking loop and a fine alignment between the received PN code and local PN code is achieved by a code tracking loop namely the delay-locked loop. Then, the output of code tracking loop, i.e., a duplicate of received PN code, is mixed to the IF direct sequence spread spectrum signal dehopped by coarse synchronization, and a monotonous intermediate frequency narrowband signal which will be fed to carrier tracking loop is obtained.III. CHARACTERISTIC OF DS/FHSS CARRIER TRACKING LOOPCompared with the carrier tracking loop in ordinarycommunication system, because of the high dynamic of the spacecraft, especially during the landing, accelerating and decelerating, the carrier tracking loop of hybrid DS/FHSS TT&C system will be influenced more severely by the Doppler Effect (up to 100KHz). Addition to that, a Doppler frequency agility resulted from the carrier frequency hopping won’t be eliminated by dehopping the frequency hopping carrier, and which becomes the main factor influencing the performance of carrier tracking loop in DS/FHSS TT&C system. The frequency of downlink signal of DS/FHSS TT&C system may be described as:)()(1)()()()(000i v i f ci f i f i f i f d +=+= where i is the sequence number of carrier frequency, )(0i f is the ith carrier frequency , )(i f d is the Doppler frequency offset during the ith hop dwell time and )(i v is the current speed of spacecraft. We can assume that the synchronization of frequency hopping pattern has been completed, and the output frequency of localfrequency synthesizer is )()()(i f i f i f o lo ∆-= , where )(i f ∆is the frequency difference between the received and local frequency, i.e., the intermediate frequency of input signal of carrier tracking loop. Passing a IF band pass filter, a IF signal, the frequency of which is )(i f ∆, is obtained.According to the relation among the velocity, carrier frequency and Doppler frequency offset, the input frequency of carrier tracking loop is derived easily as follow:)()(1)()()()(0i v i f ci f i f i f i f d in +=+=∆∆ Then, between the interval of the ith frequency and the (i+i)th frequency, the Doppler frequency agility )(i f d ∆ is generated, and can be expressed as:)]()()1()1([1)(00i v i f i v i f ci f d -++=∆ Generally speaking, we assume that the velocity of spacecraft during twoadjacen t frequency won’t change, i.e.)()1(i v i v =+, so )()(1)(0i f i v ci f d ∆∆=, which shows that the frequency agility is a function of the frequency difference of two adjacent hop and the current speed of spacecraft.Then, the input signal of the carrier tracking loop can be expressed as:)(])()()(1222sin[)(2)(0t n nT t p n f n v c t f t f t R P t s n ab +++-++∙=∑∞∞→∆∆τσπππ where P is the carrier power after the synchronization of frequency hopping pattern, )(t R is the modulated data, ∆f is the intermediate frequency, d f and τ are the rudimental frequency offset and rudimental phase offset brought from acquisition module respective. ;1)(,10=≤≤t p t otherwise 0)(=t p , T is one hop dwell time, σ is the timing error of the synchronization of frequency hopping patterns, n(t) is the additive white Gaussian noise with two-side power spectral density 2N W/Hz and c is the velocity of light.The tracking resolution is the basic description of the loop performance, and we can obtain it by the error transfer function as follow:)()(1)()()(0s KF s s s H s s s H +=-==θθθ where, F(s) is the transfer function of loop filter, K is the gain of open loop. Then we can apply the limit theorem, which is expressed as )()()(0100lim s H s s s Θ=∞→θ,toderive the steady-state tracking error. Unfortunately, the derivation of Laplaciantransfer of is seen to be impossible, so we can’t calculate the measuring error precisely and only analyze it by simulation. For the 2edorder loop, the acquisition time can be expressed as:3202nT ξωωρ∆= where, 0ω is the initial frequency offset, n ω and ξ are the natural frequency and damping factor of the tracking loop. In the hybrid DS/FHSS TT&C system, 0ω just is the frequency agility which is a function of time according to the frequency hopping pattern. Thereby, three cases are discussed.Case 1: Tp<Tc , i.e., hop dwell time is more than the loop acquisition time.The carrier tracking loop is able to acquire and track the DS/FHSS TT&C signal, but shift the unlock state immediately when the next frequency signal is fed to the loop. The loop steps to lock, unlock, re-lock, re-unlock state repeatedly for all time, and the Doppler offset can’t be extracted accurately.Case 2: Tp>Tc, i.e., hop dwell time is less than the loop acquisition time. During the acquisition state of loop, the frequency of input signal is likely to step up suddenly, and then the loop steps to the acquisition state once again. For the case, the tracking loop will step to acquisition state again and again for all time.Case 3: For the non-ideal 2ed or high-degree order loop, the acquisition band p ω∆ is limited, and the hopping frequency agility )(i f d ∆ also influences the performance of loop. When )(i f d ∆<p ω∆ , the conclusion is same as the analysis mentioned above, and when )(i f d ∆>p ω∆ , the tracking loop won’t locked the signal forever.The simulation result of 2ed order tracking loop used commonly in TT&C fieldis shown in Fig 2. The Doppler agility is plotted by broken line and the time response is denoted by real line. Fig. 2(a) shows the tracking performance without Doppler offset agility; the time response as Tp<Tc is described in Fig. 2(b), the loop state is alternating between locked and unlocked. In Fig. 2(c), the loop is acquiring signal forever. Because the frequency is changed before stepping to the locked state, the loop won’t acquire any s ignal at all time. In Fig 2(d), when )(i f d ∆>p ω∆, the tracking capability of the loop is invalid entirely.Figure 2. Time response of tracking loop with Doppler offset agility:(a) No hopping, (b) Tp<Tc , (c) Tp>Tc ,(d) )(i f d ∆>p ω∆IV. THE SCHEME OF CARRIER TRACKING LOOP AIDED BY HOPPING PATTERNThe structure of the carrier track loop aided by the hopping frequency pattern is shown in Fig 3. Generally speaking, we can assume that the velocity during the interval time between two adjacent frequency will keep a fixed value, then the dopplerfrequency offset in the next frequency interval can be calculated by the currentvelocity of spacecraft combined with carrier frequency. The is added timely to the adjustment value of the carrier NCO when the new frequency signal is fed to the loop. So the output frequency of NCO also changes synchronal as the frequency changing of input signal, and the loop keeps stable. Deserve to mentioned, before the loop stepped to steady state, the spacecraft velocity used by the scheme is given from the acquisition module. After having being locked state, then the velocity should be extracted from the loop itself directly. By this way, the loop is able to keep stable even on the high dynamic condition.Figure 3. Carrier tracking loop aided by frequency hopping pattern Besides the thermal noise jitter, the main error of carrier tracking loop aided by the frequency hopping pattern is the frequency jitter of the frequency synthesizer and timing error due to frequency pattern synchronization. The former one depends on the resolution of frequency synthesizer as other communication and we only discuss the latter one. Briefly, when the local frequency changing of the local frequency synthesizer is advanced or retarded to the one of receive signal, the aiding module will provide a frequency offset to the carrier NCO at the wrong time and the loop will step to the unlocked state at once, i.e., response of frequency step. Fortunately, when the frequency of input signal changes actually, the loop will return to the steady state rapidly. But as the increase of synchronization error, it also be likely to become too severe to meet the resolution requirement of the TT&C system.V. SIMULATIOMThe model of carrier tracking loop of hybrid DS/FHSS system is shown in Fig 3, which is built in the simulink of Matlab. The tracking loop is the standard costas loop commonly used in the TT&C field, which is able to eliminate the inference resulted form the polarity change of the modulated data [9]. To adapt the Doppler frequency change due to the spacecraft movement, the loop is designed as a 2ed order loop, and the loop filter is a 1st order filter. The simulation parameter is set according to the actual TT&C task as follows:Carrier frequency: 2.2GHz~2.3GHzAmount of frequencies: 128Frequency hopping pattern: based on m-sequenceRudimental frequency offset after acquisition: 300HzIntermediate frequency of the carrier tracking loop:4.8MHzSampling frequency: 16.3MbpsNoise Bandwidth of the loop: 10HzA. The time response on uniform motion and uniformly accelerated motionWe assume the spacecraft speed is 7.9km/s, by the relation among the Doppler frequency, carrier frequency and velocity, the frequency offset of the input IF signal of loop is obtained as Fig 4(a). The max frequency agility is up to 2.3KHz. The time response without aid is shown in the Fig 4(b) and the one with aid by hopping pattern is shown in Fig4(c). The results show that the loop without aid is unlocked completely, while the one with aid can track the carrier accurately. When the spacecraft is on the uniformly accelerated motion (the initial speed is 7.9km/s, and speed accelerator is 30g), the time response is shown in Fig 5. The same conclusion is obtained as pre-paragraph.Figure 4. The time response on uniform motion:(a)doppler frequency,(b)without aid, (c) with aid.Figure 5. Time response on uniformly accelerated motion:(a)doppler frequency,(b)without aid (c) with aidB. Tracking resolution on different hopping speedIn this simulation, the resolution of carrier tracking loop is obtained by calculating variance. The relation between tracking resolution and hopping speed is shown in Fig 6 on different input SNR and the minimum value insuring the demodulating correctly in TT&C system is 13 dB. The result of simulation testified that the resolution is not sensitive to the hopping speed and the scheme is very robust for different hopping speed.Figure 6. Stead-state tracking resolution vs hopping speedC. Tracking resolution on different timing error of frequency pattern synchronizationFor carrier tracking loop aided by the frequency hopping pattern, according to the above discussion the main factor impacting the stability of loop is the timing error caused by the patterns synchronization. Fig 7 shows the stead-state tracking accuracies on different timing error of synchronization pattern on different input SNR. The measuring error is increase as increasing of timing error and the measurement error resulted from the SNR even can be ignored when the time error is up to some specified value. Consequently, we can infer that the track accuracy won’t meet the requirement of TT&C system finally, and the problem needs to be researched in the future.Figure 7. Stead-state tracking resolution vs timing error of pattern synchronizationVI. CONCLUSIONSIn the hybrid DS/FHSS TT&C system, the rudimental Doppler frequency agility leads the carrier tracking loop holding on frequency step response state ceaselessly, so it is hardy to extract the Doppler frequency offset precisely formeasuring the distance and velocity. By analyzing effect of frequency agility to the performance of the tracking, a tracking aided by frequency hopping pattern and current spacecraft velocity is presented. A compensated frequency is added to the tracking loop as carrier frequency hopping, and the accuracy of this method is demonstrated by simulation.REFERENCES[1] L. Simone, N. Salerno, a nd M. Maffei, “Frequency-Hopping Techniques for Secure Satellite TT&C: System Analysis & Trade-Offs”, Satellite and Space Communications, 2006 International Workshop on , Sept.2006, pp.13-17, dio:10.1109/WSSC.2006.255980.[2] Don Torrieri, Frequency-Hopping Communication Systems, Amy research laboratory, Mar.2003.[3]M.K.Simon, J.K.Omura, Robert A.Scholtz and Barry K.Levitt, Spread Spectrum Communication Handbook. Boston: McGraw-Hill, 2003.[4]D.Akopian, “Fast FFT based GPS satellite acquisition Methods,” Proc.Inst. Elect. Eng. Radar, Sonar, Navig., vol. 152, no. 4, pp.227-286, Aug.2005.[5]S.Yoon,I.Son, and S.Y.Kim, “Code acquisition for DS/SS communications in non-Gaussian impulsive channels,” IEEE Trans. Commun., vol. 52, no.5, pp.909-919, May.2005.[6] Roland E. Best, Phase-Locked Loops: Design, Simulation, and Application (5th Edition). Boston: McGraw-Hill, 2003.[7] S.Hinedi and B. Shah, “Acquisition Performance of Various QPSK Carrier Tracking Loops,” IEEE mun., vol.40, no.9, pp.1426-1429, Sep.1992.[8]I.N.Psaromiligkos, S.N Batalama, and M.J.Medley, “Rapid combined synchronization/demodulation structures for DS-CDMA systems.I.algorithmic developments,” IEEE Trans. Commun., vol.51, no.6, pp.983-994,June 2003.[9]Elliott D.Kaplan,UNDERSTANDING GPS Principles and Applications. Artech House, 1996.对载波跟踪混合DS /跳频扩频测控系统的研究摘要由于载波频率调频的影响，DS/FHSS（直接序列/跳频扩频）TT&C（测控）系统的载波跟踪回路的输入信号具有多普勒频移灵活的特征。

通信外文翻译外文文献英文文献及译文

通信外文翻译外文文献英文文献及译文Communication SystemA generalized communication system has the following components:(a) Information Source. This produces a message which may be written or spoken words, or some form of data.(b) Transmitter. The transmitter converts the message into a signal, the form of which is suitable for transmission over the communication channel.(c) Communication Channel. The communication channel is the medium used transmit the signal, from the transmitter to the receiver. The channel may be a radio link or a direct wire connection.(d) Receiver. The receiver can be thought of as the inverse of the transmitter. Itchanges the received signal back into a message and passes the message on to its destination which may be a loudspeaker，teleprinter or computer data bank.An unfortunate characteristic of all communication channels is that noise is added to the signal. This unwanted noise may cause distorionsof sound in a telephone, or errors in a telegraph message or data.Frequency Diversion MultiplexingFrequency Diversion Multiplexing(FDM) is a one of analog technologies. A speech signal is 0~3 kHz, single sideband amplitude (SSB) modulation can be used to transfer speech signal to new frequency bands,four similar signals, for example, moved by SSB modulation to share the band from 5 to 20 kHz. The gaps between channels are known as guard spaces and these allow for errors in frequency, inadequate filtering, etc in the engineered system.Once this new baseband signal, a "group" of 4 chEmnels, has been foimed it ismoved around the Lrunk network as a single unit. A hierarchy can be set up withseveral channels fonning a "group". several groups a "supergroup" and several"supergraup" eicher a "nmsrergroup" or "hypergroup".Groups or supergroups are moved around as single units by the communicationsequipment and it is not necessary for the radios to know how many channels are involved. A radio can handle a supergroup provided sufficient bandwidth is available. The size of the groups is a compromise as treating each channel individually involves far more equipment because separate filters, modulators and oscillators are required for every channel rather than for each group. However the failure of one module will lose all of the channels associated with a group.Time Diversion MultiplexingIt is possible, with pulse modulation systems, to use the between samples to transmit signals from other circuits. The technique is knownas time diversion multiplexing (TDM). To do this, it is necessary to employ synchronized switches at eachend of the communication links to enable samples to be transmittedin turn, from each of several circuits. Thus several subscribers appear to use the link simultaneously. Although each user only has periodic short time slots, the original analog signalsbetween samples can be reconstituted at the receiver.Pulse Code ModulationIn analog modulation, the signal was used to modulate the amplitude or frequency of a carrier, directly. However, in digital modulation a stream of pulse, representing the original，is created. This stream is then used to modulate a carrier or alternatively is transmitted directly over a cable. Pulse Code Modulation (PCM) is one of the two techniques commonly used.All pulse systems depend on the analog waveform being sampled at regular intervals. The signal created by sampling our analog speech input is known as pulse amplitude modulation. It is not very useful in practice but is used as an intermediate stage towards forming a PCM signal. It will be seen later that most of the advantages of digital modulation come from the transmitted pulses having two levels only, this being known as a binary system. In PCM the height of each sample is converted into a binary number. There are three step in the process of PCM: sampling, quantizing and coding.Optical Fiber CommunicationsCommunication may be broadly defined as the transfer of information from one point to another. When the information is to be conveyed over any distance acommunication system is usually required. Within a communication system the information transfer is frequently achieved by superimposing or modulating the information on to an electromagnetic wave which acts as a carrier for the informationsignal. This modulated carrier is then transmitted to the required destination where it is received and the original information signal is obtained by demodulation. Sophisticated techniques have been developed for this process by using electromagnetic carrier wavesoperating at radio frequencies as well as microwave and millimeter wave frequencies. However，拻 communication?may also be achieved by using an electromagneticcarrier which is selected from the optical range of frequencies.In this case the information source provides an electrical signal to a transmitter comprising an electrical stage which drives an optical source to give modulation of the light-wave carrier. The optical source which provides the electrical-optical conversionmay be either a semiconductor laser or light emitting diode (LED). The transmission medium consists of an optical fiber cable and the receiver consists of an optical detector which drives a further electrical stage and hence provides demodulation optical carrier. Photodiodes (P-N, P-I-N or avalanche) and , in some instances,phototransistor and photoconductors are utilized for the detection of the optical signal and the electrical-optical conversion. Thus there is a requirement for electrical interfacing at either end of the optical link and at present the signal processing is usually performed electrically.The optical carrier may be modulated by using either an analog or digital information signal. Analog modulation involves the variation of the light emitted from the optical source in a continuous manner. With digital modulation, however, discrete changes in the light intensity are obtained (i.e. on-off pulses). Although often simpler to implement, analog modulation with an optical fiber communication system is lessefficient, requiring a far higher signal to noise ratio at the receiver than digital modulation. Also, the linearity needed for analog modulation is not always provided by semiconductor optical source, especially at high modulation frequencies. For thesereasons，analog optical fiber communications link are generally limited to shorter distances and lower bandwidths than digital links.Initially, the input digital signal from the information source is suitably encoded for optical transmission. The laser drive circuit directly modulates the intensity of the semiconductor laser with the encoded digital signal. Hence a digital optical signal is launched into the optical fiber cable. The avalanche photodiode detector (APD) is followed by a fronted-end amplifier and equalizer orfilter to provide gain as well as linear signal processing and noise bandwidth reduction. Finally, the signal obtained isdecoded to give the original digital information.Mobile CommunicationCordless Telephone SystemsCordless telephone system are full duplex communication systems that use radio to connect a portable handset to a dedicated base station，which is then connected to adedicated telephone line with a specific telephone number on the public switched telephone network (PSTN) .In first generation cordless telephone systems5(manufactured in the 1980s), the portable unit communications only to the dedicatedbase unit and only over distances of a few tens of meters.Early cordless telephones operate solely as extension telephones to a transceiver connected to a subscriber line on the PSTN and are primarily for in-home use.Second generation cordless telephones have recently been introduced which allowsubscribers to use their handsets at many outdoor locations within urban centers such as London or Hong Kong. Modern cordless telephones are sometimes combined with paging receivers so that a subscriber may first be paged and then respond to the pageusing the cordless telephone. Cordless telephone systems provide the user with limited range and mobility, as it is usually not possible to maintain a call if the user travels outside the range of the base station. Typical second generation base stations provide coverage ranges up to a few hundred meters.Cellular Telephone SystemA cellular telephone system provides a wireless connection to the PSTN for any user location within the radio range of the system.Cellular systems accommodate alarge number of users over a large geographic area, within a limited frequency spectrum. Cellular radio systems provide high quality service that is often comparable to that of the landline telephone systems. High capacity is achieved by limiting the coverage of each base station transmitter to a small geographic area called a cell so that the same radio channels may be reused by another base station located some distance away. A sophisticated switching technique called a handoff enables a call to proceeduninterrupted when the user moves from one cell to another.A basic cellular system consists of mobile station, base stations and a mobile switching center (MSC). The Mobile Switching Center is sometimes called a mobiletelephone switching office (MTSO), since it is responsible for connecting all mobiles to the PSTN in a cellular system. Each mobilecommunicates via radio with one of the base stations and may be handed-off to any number of base stations throughout the duration of a call. The mobile station contains a transceiver, an antenna, and control circuitry，and may be mounted in a vehicle or used as a portable hand-held unit. Thebase stations consists of several transmitters and receivers which simultaneously handlefull duplex communications and generally have towers which support several transmitting and receiving antennas. The base station serves as a bridge between all mobile users in the cell and connects the simultaneous mobile calls via telephone linesor microwave links to the MSC. The MSC coordinates the activities of all the base stations and connects the entire cellular system to the PSTN. A typical MSC handles 100000 cellular subscribers and 5000 simultaneous conversations at a time, andaccommodates all billing and system maintenance functions, as well. In large cities, several MSCs are used by a single carrier.Broadband CommunicationAs can be inferred from the examples of video phone and HDTV, the evolution offuture communications will be via broadband communication centered around video signals. The associated services make up a diverse set of high-speed and broadbandservices ranging from video services such as video phone，video conferencing，videosurveillance, cable television (CATV) distribution, and HDTV distribution to the high-speed data services such as high-resolution image transmission, high-speed datatransmission, and color facsimile. The means of standardizing these various broadbandcommunication services so that they can be provided in an integrated manner is no other than the broadband integrated services digital network (B-ISDN). Simple put, therefore,the future communications network can be said to be a broadband telecommunicationsystem based on the B-ISDN.For realization of the B-ISDN, the role of several broadband communicationtechnologies is crucial. Fortunately, the remarkable advances in the field of electronics and fiber optics have led to the maturation of broadband communication technologies.As the B-ISDN becomes possible on the optical communication foundation, the relevant manufacturing technologies for light-source and passive devices and for optical fiberhave advanced to considerable levels. Advances in high-speed device and integratedcircuit technologies for broadband signal processing are also worthy of close attention. There has also been notable progress in software, signal processing, and video equipment technologies. Hence, from the technological standpoint, the B-ISDN hasfinally reached a realizable state.On the other, standardization activities associated with broadband communication have been progressing. The Synchronous Optical Network (SONET) standardization centered around the T1 committee eventually bore fmit in the form of the Synchronous Digital Hierarchy (SDH) standards of the International Consultative Committee in Telegraphy and Telephony (CCITT), paving the way for synchronous digital transmission based on optical communication. The standardization activities of the 5integrated services digital network (ISDN), which commenced in early 1980s with the objective of integrating narrowband services, expanded in scope with the inclusion of broadband services, leading to the standardization of the B-ISDN in late1980抯 and establishing the concept of asynchronous transfer mode (ATM)communication in process. In addition, standardization of various video signals is becoming finalized through the cooperation among such organizations as CCITT, the International Radio-communications Consultative Committee (CCIR), and theInternational Standards Organization (ISO), and reference protocols for high-speedpacket communication are being standardized through ISO, CCITT, and the Institute of Electrical and Electronics Engineer (IEEE).Various factors such as these have made broadband communication realizable.5Therefore, the 1990s is the decade in which matured broadband communicationtechnologies will be used in conjunction with broadband standards to realize broadband communication networks. In the broadband communication network, the fiber opticnetwork will represent the physical medium for implementing broadband communication, while synchronous transmission will make possible the transmission of broadband service signals over the optical medium. Also, the B-ISDN will be essentialas the broadband telecommunication network established on the basis of optical medium and synchronous transmission and ATM is the communication means that enables the realization of the B-ISDN. The most important of the broadband services to be providedthrough the B-ISDN are high-speed data communication services and videocommunication services.Image AcquisitionA TV camera is usually used to take instantaneous images and transform them into electrical signals, which will be further translated into binary numbers for the computer to handle. The TV camera scans oneline at a time. Each line is further divided into hundreds of pixels. The whole frame is divided into hundreds (for example, 625) of lines.The brightness of a pixel can be represented by a binary number with certain bits, for example, 8 bits. The value of the binary number varies from 0 to 255, a range great enough to accommodate all possible contrast levels of images taken from real scene.These binary numbers are sorted in an RAM (it must have a great capacity) ready for processing by the computer.Image ProcessingImage processing is for improving the quality of the images obtained. First, it is necessary to improve the signal-to-noise ratio. Here noise refers to any interference flaw or aberation that obscure the objects on the image. Second, it is possible to improve contrast, enhance sharpness of edges between images through various computational means.Image AnalysisIt is for outlining all possible objects that are included in the scene. A computer program checks through the binary visual informationin store for it and identifies specific feature and characteristics of those objects. Edges or boundaries are identifiablebecause of the different brightness levels on either side of them. Usingcertain algorithms, the computer program can outline all possible boundaries of the objects in the scene. Image analysis also looks for textures and shadings between lines.Image ComprehensionImage Comprehension means understanding what is in a scene. Matching the prestored binary visual information with certain templates which represent specific objects in a binary form is technique borrowed from artificial intelligence, commonly referred to as "templeite matching"emplate matching? One by one,the templates are checked against the binary information representing the scene. Once a match occurs, an object is identified. The template matching process continues until all possible objects in the scene have been identified, otherwise it fails.通信系统一般的通信系统由下列部分组成:信源。

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中英文翻译附件1：外文资料翻译译文通用移动通信系统的回顾1.1 UMTS网络架构欧洲/日本的3G标准，被称为UMTS。

UMTS是一个在IMT-2000保护伞下的ITU-T 批准的许多标准之一。

随着美国的CDMA2000标准的发展，它是目前占主导地位的标准，特别是运营商将cdmaOne部署为他们的2G技术。

在写这本书时，日本是在3G 网络部署方面最先进的。

三名现任运营商已经实施了三个不同的技术：J - PHONE 使用UMTS，KDDI拥有CDMA2000网络，最大的运营商NTT DoCoMo正在使用品牌的FOMA（自由多媒体接入）系统。

FOMA是基于原来的UMTS协议，而且更加的协调和标准化。

UMTS标准被定义为一个通过通用分组无线系统（GPRS）和全球演进的增强数据技术（EDGE）从第二代GSM标准到UNTS的迁移，如图。

这是一个广泛应用的基本原理，因为自2003年4月起，全球有超过847万GSM用户，占全球的移动用户数字的68％。

重点是在保持尽可能多的GSM网络与新系统的操作。

我们现在在第三代（3G）的发展道路上，其中网络将支持所有类型的流量：语音，视频和数据，我们应该看到一个最终的爆炸在移动设备上的可用服务。

此驱动技术是IP协议。

现在，许多移动运营商在简称为2.5G的位置，伴随GPRS的部署，即将IP骨干网引入到移动核心网。

在下图中，图2显示了一个在GPRS网络中的关键部件的概述，以及它是如何适应现有的GSM基础设施。

SGSN和GGSN之间的接口被称为Gn接口和使用GPRS隧道协议（GTP的，稍后讨论）。

引进这种基础设施的首要原因是提供连接到外部分组网络如，Internet或企业Intranet。

这使IP协议作为SGSN和GGSN之间的运输工具应用到网络。

这使得数据服务，如移动设备上的电子邮件或浏览网页，用户被起诉基于数据流量，而不是时间连接基础上的数据量。

3G网络和服务交付的主要标准是通用移动通信系统，或UMTS。

首次部署的UMTS是发行'99架构，在下面的图3所示。

在这个网络中，主要的变化是在无线接入网络（RAN的）CDMA空中接口技术的引进，和在传输部分异步传输模式作为一种传输方式。

这些变化已经引入，主要是为了支持在同一网络上的语音，视频和数据服务的运输。

核心网络保持相对不变，主要是软件升级。

然而，随着目前无线网络控制器使用IP与3G的GPRS业务支持节点进行通信，IP协议进一步应用到网络。

未来的进化步骤是第4版架构，如图4。

在这里，GSM的核心被以语音IP技术为基础的IP网络基础设施取代。

海安的发展分为两个独立部分：媒体网关（MGW）和MSC服务器（MSS）的。

这基本上是打破外连接的作用和连接控制。

一个MSS可以处理多个MGW，使网络更具有扩展性。

因为现在有一些在3G网络的IP云，合并这些到一个IP或IP/ ATM骨干网是很有意义的（它很可能会提供两种选择运营商）。

这使IP权利拓展到整个网络，一直到BTS(基站收发信台)。

这被称为全IP网络，或推出五架构，如图五所示。

在HLR/ VLR/VLR/EIR被推广和称为HLR的子系统（HSS）。

现在传统的电信交换的最后残余被删除，留下完全基于IP协议的网络运营，并推广了许多服务类型的运输。

实时服务通过引入一个新的网络域名得到支持，即IP 多媒体子系统（IMS）。

目前3GPP作用于第6版，意在包含冷冻版本没有涵盖所有方面。

有些人称UMTS 第6版为4G和它包括热点无线电接入技术，如无线局域网互联互通的问题。

1.2 UMTS的FDD和TDD像任何CDMA系统，UMTS需要一个宽的频带，在这个频带上有效地传播信号。

该系统的特点是芯片的速度，芯片是一个符号的CDMA代码的宽度。

UMTS使用的芯片速率为3.84Mchips/秒，这转换到所需的频谱载波宽度为5MHz。

由于这比现有的cdmaOne系统所需的1.25MHz带宽要宽，UNTS空中接口被称为“宽带”CDMA.实际上在UMTS下有两个无线电技术：UMTS软盘驱动器和时分双工。

FDD代表频分双工，如GSM，通过把它们放置在不同的频率信道分离为交通上行和下行。

因此，一个运营商必须有一对频率分配，使他们能够运行网络，即术语成对频谱。

TDD或时分双工只需要一个频率通道，上行和下行流量是在不同的时间分开发送。

ITU-T 的频谱使用，如在图6所示。

对于FDD是1920 - 1980MHz的为上行流量，2110-2170MHz 为下行的。

运营商需要的最小分配是两个成对5MHz的信道，一个用于上行，一个用于下行的，两者相分离190MHz。

然而，为了给客户提供全面的覆盖和服务，建议给予每个运营商三个信道。

考虑到频谱分配，有12对可用的渠道，现在许多国家都完成了这个频谱的许可过程，每个许可证配置两个到四个信道。

这趋向给运营商造成一个昂贵的花费，因为一些国家的监管部门，特别是在欧洲，已经将这些许可证拍卖给出价最高的人。

这就造成了频谱费用在一些国家高达数十亿美元。

时分双工（TDD）系统，只需要一个5MHz的带宽在其中操作，通常被称为非成对频谱。

UMTS FDD和TDD之间的差异只有在较低层明显，特别是在无线接口。

在更高的层次，两个系统的运作大部分是相同的。

正如它的名字表明，TDD系统通过把它们放置在不同的时间空挡分为上行流量和下行流量。

正如我们以后可以看到的，UMTS使用一个分为15个相等的时隙的10ms帧结构。

时分双工可以分配这些为上行或下行，在一个确定的帧结构中这两者间可以有一个或多个断点。

以这种方式，这是非常适合数据包通信的，因为这对于不对称的通信流的动态标注可以有极大的灵活性。

TDD系统真的不应该被视为一个独立的网络，而是作为一个FDD系统的补充，提供更高的数据传输率的热点覆盖。

由于站点之间的干扰，它相当不合适用作大规模部署，因为一个基站可以尝试从UE检测微弱信号，这被来自邻近基站的相同频率的相对较强的信号阻止了。

时分双工对于小面积的室内覆盖是理想的。

由于FDD是目前正在发展的主要的接入技术，这里介绍的解释将完全专注于这个系统。

1.3 UMTS承载模型移动设备连接到UMTS网络的程序可以分成两领域：接入层（AS）和非接入层（NAS）。

接入层涉及所有提供普遍服务的非接入层和子系统阶层。

在UMTS接入层包括无线接入的所有元素网络，包括潜在的ATM传输网络，各种机制提供可靠的信息交换等。

所有的非接入层功能都在移动设备和核心网络之间，例如，移动性管理。

图7显示了结构模型。

AS通过使用服务接入点（SAPS）与NAS交互。

UMTS无线接入网（UTRAN）提供NAS和AS功能的分离，并允许AS功能在UTRAN 中被完全控制和实施。

两大UTRAN的接口是UU，这是移动设备之间的接口，或者用户设备（UE）和UTRAN之间，Iu，这是UTRAN和核心网之间的接口。

这些接口都可以分为控制平面和用户平面，每个都有适当的协议功能。

承载服务是两点间的连接，这是由一组特定的特点定义的。

在UMTS的情况下，使用无线接入承载提供承载服务。

无线接入承载（RAB）被定义为用户设备和核心网络之间的服务，即接入层（ieUTRAN）为非接入层提供用户数据传输。

一个RAB可以由一些支流组成，这是数据流在有不同的QoS特性的RAB流向核心网络，如不同的可靠性。

一个常见的例子是不同类别的位有不同的位错误率，可以实现不同的RAB子流。

RAB子流在RAB建立和释放的同时建立和释放，并通过相同的传输承载一起传输。

无线电链路被定义为一个单一的用户设备（UE）和一个单一的UTRAN接入点之间的逻辑关联，如一个RNC。

它实际上是由一个或多个无线承载组成和不应和无线接入承载混淆。

在UTRAN内部来看，总体架构模型在下面的图8所示。

现在显示的是节点B基站（BTS）和无线网络控制器（RNC）组件，以及它们各自的内部接口。

UTRAN分为被称为无线网络子系统（RNS）的块，其中每个RNS由一个控制RNC和控制下的所有基站组成。

UMTS的独特之处是RNS之间的接口，Iur接口，在交接过程起了关键作用。

基站和RNC之间的接口是Iub接口。

所有“I”接口：Iu，Iur和Iub，currently3将ATM用作传输层。

在ATM的背景下，BTS被看作是ATM网络的主机访问，在这个网络中RNC是一个ATM交换机。

因此，Iub是一个UNI接口，而Iu和Iur接口被认为是NNI，如图9所示。

这种区别是因为基站到RNC的链接是一个点至点连接，在这个连接中一个基站或RNC只和与它直接连接的RNC或基站通信，并且不会要求和其他网络元素的元素。

对于每个用户连接到核心网络，这里只有一个RNC，保持UE和核心网域之间的联系，在图10中突出显示。

RNC是指服务RNC或SRNC。

SRNC加上在其控制下的基站被称为SRNS。

这是一个只以UE为参考的逻辑定义。

在一个RNS中，控制基站的RNC被称为控制RNC或CRNC。

这是以基站为参考，其控制下的部分和所有常见的和共享的渠道内。

因为UE移动，它可能执行软或硬切换到另一个蜂窝。

在软切换的情况下，SRNC 将启动新的连接到新的基站。

新的基站应该是在另一个RNC控制下，SRNC中也会提醒这个新的RNC启动沿Iur接口连接。

UE现在有两个连接，一个直接连接SRNC，第二个通过新的RNC连接Iur接口。

在这种情况下，这个新的RNC在逻辑上被称为漂移RNC或DRNC，见图10。

它不涉及任何呼叫处理，只是将它中继到SRNC以连接核心网络，总之，SRNC和DRNC通常与UE相关联，CRNC与BTS相关联。

由于这些是逻辑功能，一个单一的RNC是能够处理所有这些功能是很正常的做法。

一个UE连接到基站，它的SRNC并不是这个基站的控制RNC，这种情况可能会出现。

在这种情况下，这个网络可以调用SRNC的搬移程序来移动核心网络的连接。

在第3节将介绍此过程。

附件2：外文原文Review of UMTS1.1 UMTS Network ArchitectureThe European/Japanese 3G standard is referred to as UMTS. UMTS is one of a number of standards ratified by the ITU-T under the umbrella of IMT-2000. It is currently the dominant standard, with the US CDMA2000 standard gaining ground, particularly with operators that have deployed cdmaOne as their 2G technology. At time of writing,Japan is the most advanced in terms of 3G network deployment. The three incumbent operators there have implemented three different technologies: J-Phone is using UMTS,KDDI has a CDMA2000 network, and the largest operator NTT DoCoMo is using a system branded as FOMA (Freedom ofMultimedia Access). FOMA is based on the original UMTS proposal, prior to its harmonization and standardization.The UMTS standard is specified as a migration from the second generation GSM standard to UMTS via the General Packet Radio System (GPRS) and Enhanced Data for Global Evolution (EDGE), as shown in Figure. This is a sound rationale since as of April 2003, there were over 847 Million GSM subscribers worldwide1, accounting for68% of the global cellular subscriber figures. The emphasis is on keeping as much ofthe GSM network as possible to operate with the new system.We are now well on the road towards Third Generation (3G), where the network will support all traffic types: voice, video and data, and we should see an eventual explosion in the services available on the mobile device. The driving technology for this is the IP protocol. Many cellular operators are now at a position referred to as 2.5G, with the deployment of GPRS, which introduces an IP backbone into the mobile core network.The diagram below, Figure 2, shows an overview of the key components in a GPRS network, and how it fits into the existing GSM infrastructure.The interface between the SGSN and GGSN is known as the Gn interface and uses the GPRS tunneling protocol (GTP, discussed later). The primary reason for the introduction of this infrastructure is to offer connections to external packet networks, such as the Internet or a corporate Intranet.This brings the IP protocol into the network as a transport between the SGSN and GGSN. This allows data services such as email or web browsing on the mobile device,with users being charged based on volume of data rather than time connected.The dominant standard for delivery of 3G networks and services is the Universal Mobile Telecommunications System, or UMTS. The first deployment of UMTS is the Release ’99 architecture, shown below in Figure 3.In this network, the major change is in the radio access network (RAN) withthe introduction of CDMA technology for the air interface, and ATM as a transport in the transmission part. These changes have been introduced principally to support the transport of voice, video and data services on the same network. The core network remains relatively unchanged, with primarily software upgrades. However, the IP protocol pushes further into the network with the RNC now communicating with the 3G SGSN using IP.The next evolution step is the Release 4 architecture, Figure 4. Here, the GSM core is replaced with an IP network infrastructure based around Voice over IP technology.The MSC evolves into two separate components: a Media Gateway (MGW) and an MSC Server (MSS). This essentially breaks apart the roles of connection and connection control. An MSS can handle multiple MGWs, making the network more scaleable.Since there are now a number of IP clouds in the 3G network, it makes sense to merge these together into one IP or IP/ATM backbone (it is likely both options will be available to operators.) This extends IP right across the whole network, all the way to the BTS.This is referred to as the All-IP network, or the Release 5 architecture, as shown in Figure 5. The HLR/VLR/EIR are generalised and referred to as the HLR Subsystem(HSS).Now the last remnants of traditional telecommunications switching are removed, leaving a network operating completely on the IP protocol, and generalised for the transport of many service types. Real-time services are supported through the introduction of a new network domain, the IP Multimedia Subsystem (IMS).Currently the 3GPP are working on Release 6, which purports to cover all aspects not addressed in frozen releases. Some call UMTS Release 6 4G and it includes such issues as interworking of hot spot radio access technologies such as wireless LAN.1.2 UMTS FDD and TDDLike any CDMA system, UMTS needs a wide frequency band in which to operate to effectively spread signals. The defining characteristic of the system is the chip rate, where a chip is the width of one symbol of the CDMA code. UMTS uses a chip rate of 3.84Mchips/s and this converts to a required spectrum carrier of 5MHz wide. Since this is wider than the 1.25MHz needed for the existing cdmaOne system, the UMTS air interface is termed ‘wideband’ CDMA.There are actually two radio technologies under the UMTS umbrella: UMTS FDD and TDD. FDD stands for Frequency Division Duplex, and like GSM, separates traffic in the uplink and downlink by placing them at different frequency channels. Therefore an operator must have a pair of frequencies allocated to allow them to run a network, hence the term ‘paired spectrum’. TDD or Time Division Duplex requires only one frequency channel, and uplink and downlink traffic are separated by sending them at different times. The ITU-T spectrum usage, as shown in Figure 6, for FDD is 1920- 980MHz for uplink traffic, and 2110-2170MHz for downlink. The minimum allocation an operator needs is two paired 5MHz channels, one for uplink and one for downlink, at a separation of 190MHz. However, to provide comprehensive coverage and services, it is recommended that an operator be given three channels. Considering the spectrum allocation, there are 12 paired channels available, and many countries have now completed the licencing process for this spectrum, allocating between two and four channels per licence. This has tended to work out a costly process for operators, since the regulatory authorities in some countries, notably in Europe, have auctioned these licences to the highest bidder. This has resulted in spectrum fees as high as tens of billions of dollars in some countries.The Time Division Duplex (TDD) system, which needs only one 5MHz band in which to operate, often referred to as unpaired spectrum. The differences between UMTS FDD and TDD are only evident at the lower layers, particularly on the radio interface. At higher layers, the bulk of the operation of the two systems is the same. As the name suggests, the TDD system separates uplink and downlink traffic by placing them in different time slots. As will be seen later, UMTS uses a10ms frame structure which is divided into 15 equal timeslots. TDD can allocate these to be either uplink or downlink,with one or more breakpoints between the two in a frame defined. In this way, it is well suited to packet traffic, since this allows great flexibility in dynamically dimensioning for asymmetry in traffic flow.The TDD system should not really be considered as an independent network, but rather as a supplement for an FDD system to provide hotspot coverage at higher data rates. It is rather unsuitable for large scale deployment due to interference between sites, since a BTS may be trying to detect a weak signal from a UE, which is blocked out by a relatively strong signal at the same frequency from a nearby BTS. TDD is ideal for indoor coverage over small areas.Since FDD is the main access technology being developed currently, the explanations presented here will focus purely on this system.1.3 UMTS Bearer ModelThe procedures of a mobile device connecting to a UMTS network can be split into two areas: the access stratum (AS) and the non-access stratum (NAS). The access stratum involves all the layers and subsystems that offer general services to the non-access stratum. In UMTS, the access stratum consists of all of the elements in the radio access network, including the underlying ATM transport network, and the various mechanisms such as those to provide reliable information exchange. All of the non-access stratum functions are those between the mobile device and the core network, for example, mobility management. Figure 7 shows the architecture model. The AS interacts with the NAS through the use of service access points (SAPs).UMTS radio access network (UTRAN) provides this separation of NAS and AS functions, and allows for AS functions to be fully controlled and implemented within the UTRAN. The two major UTRAN interfaces are the Uu, which is the interface between the mobile device, or User Equipment (UE) and the UTRAN, and the Iu, which is the interface between the UTRAN and the core network. Both of these interfaces can be divided into control and user planes each withappropriate protocol functions.A Bearer Service is a link between two points, which is defined by a certain set of characteristics. In the case of UMTS, the bearer service is delivered using radio access bearers.A Radio access bearer (RAB) is defined as the service that the access stratum (i.e.UTRAN) provides to the non-access stratum for transfer of user data between the User Equipment and Core Network. A RAB can consist of a number of subflows, which are data streams to the core network within the RAB that have different QoS characteristics,such as different reliabilities. A common example of this is different classes of bits with different bit error rates can be realised as different RAB subflows. RAB subflows are established and released at the time the RAB is established and released, and are delivered together over the same transport bearer.A Radio Link is defined as a logical association between a single User Equipment (UE) and a single UTRAN access point, such as an RNC. It is physically comprised of one or more radio bearers and should not be confused with radio access bearer.Looking within the UTRAN, the general architecture model is as shown in Figure 8 below. Now shown are the Node B or Base Station (BTS) and Radio Network Controller (RNC) components, and their respective internal interfaces. The UTRAN is subdivided into blocks referred to as Radio Network Subsystems (RNS), where each RNS consists of one controlling RNC (CRNC) and all the BTSs under its control. Unique to UMTS is the interface between RNSs, the Iur interface, which plays a key role in handover procedures. The interface between the BTS and RNC is the Iub interface.All the ‘I’ interfaces: Iu, Iur and Iub, currently3 use ATM as a transport layer. In the context of ATM, the BTS is seen as a host accessing an ATM network, within which the RNC is an ATM switch. Therefore, the Iub is a UNI interface, whereas the Iu and Iur interfaces are considered to be NNI, as illustrated in Figure 9.This distinction is because the BTS to RNC link is a point-to-point connectionin that a BTS or RNC will only communicate with the RNC or BTS directly connected to it, and will not require communication beyond that element to another network element.For each user connection to the core network, there is only one RNC, which maintains the link between the UE and core network domain, as highlighted in Figure 10. This RNC is referred to as the serving RNC or SRNC. That SRNC plus the BTSs under its control is then referred to as the SRNS. This is a logical definition with reference to that UE only. In an RNS, the RNC that controls a BTS is known as the controlling RNC or CRNC. This is with reference to the BTS, cells under its control and all the common and shared channels within.As the UE moves, it may perform a soft or hard handover to another cell. In the case of a soft handover, the SRNC will activate the new connection to the new BTS. Should the new BTS be under the control of another RNC, the SRNC will also alert this new RNC to activate a connection along the Iur interface. The UE now has two links, one directly to the SRNC, and the second, through the new RNC along the Iur interface. In this case, this new RNC is logically referred to as a drift RNC or DRNC, see Figure 10. It is not involved in any processing of the call and merely relays it to the SRNC for connection to the core. In summary, SRNC and DRNC are usually associated with the UE and the CRNC is associated with the BTS. Since these are logical functions it is normal practice that a single RNC is capable of dealing with all these functions.A situation may arise where a UE is connected to a BTS for which the SRNC is not the CRNC for that BTS. In that situation, the network may invoke the Serving RNC Relocation procedure to move the core network connection. This process is described inSection 3.。

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