通信工程移动通信中英文对照外文翻译文献
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
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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。
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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.。