10级通信工程专业英语翻译
通信工程毕业设计外文翻译--下一代无线宽带的目标(4G—5G)
附录一、英文原文:Goals Of True Broad band’s Wireless Next Wave(4G-5G)K.R.Santhi,Prof.V.K.Srivastava,G.SenthilKumaran,Eng. Albert Butare.Kigali Institute of Science Technology and Management (KIST),B.P.3900, Kigali,Rwanda.AbstractAs access technology increases, voice, video,multimedia, and broadband data services are becomingintegrated into the same network. Fourth Generation (4G)is the next generation of wireless networks that will replacethird Generation (3G) networks sometimes in future. 4G isintended to provide high speed, high capacity, low cost perbit, IP based services.4G is all about an integrated, globalnetwork that’s based on an open system approach. The goalof 4G i s to “replace the current proliferation of core cellularnetworks with a single worldwide cellular core networkstandard based on IP for control, video, packet data andV oIP. But while 3G haven’t quite arrived, researchers wantto contribute their ideas to the development of an as-yetundefined "wireless world" that could become operationalby around 2010. This paper deals with the fundamentalsand issues of networks, technologies, spectrum, standards,terminals, services of 4G and about the visions that thenetwork operators and service providers see for theevolution of 4G mobile systems and where is future researchfrom their perspective necessary?Keywords:Wireless, 4G, W-OFDM, MC-CDMA, LAS-CDMA,UWB.I. INTRODUCTIONWhile carriers and handset manufacturers obviously havetheir hands full with 3G, some companies are alreadylooking beyond this next generation of wirelesstechnology and networks. 4G is simply an initiative byacademic R&D labs to move beyond the limitations andproblems of 3G which is having trouble getting deployedand meeting its promised performance and throughput.While this 3G has not completely reached researchers andvendors are expressing growing interest in 4G why? Twomain areas are addressed in these initiatives: An increaseof capacity in the radio link and seamless mobility acrossheterogeneous access networks. Section 2 discusses aboutthe issues of 3G that has created interest towards 4Gdevelopments.Section 3 about evolution and comparison,Section 4 describes about the goals and the vision, section5 explains about some of the technologies for 4G, and inother following sections the applications, the research andother issues for 4G developments are discussed.II. WHY THE LEAP TOWARDS 4G?3G networks are in a very painful phase of theirdevelopment, with early trials yielding disappointingresults, costs ballooning, technical glitches, and networkoperators being forced to deflate expectations based onunrealistic hype. Despite the hype surrounding thehigher-speed 3G mobile networks now underconstruction, the reasons for the leap towards 4G are:A. PerformanceIndustry skeptics say that users will not be able to takeadvantage of rich multimedia content across wirelessnetworks with 3G. 4G communications will featureextremely high-quality video equal to that of high-definitiontelevision. In addition, it will enable wirelessdownloads at speeds exceeding 100 Mbps, about 260times than 3G wireless network.B. InteroperabilityThere are multiple standards for 3G making it difficult toroam and interoperate across networks. We need a globalstandard that provides global mobility and serviceportability so that service provider would no longer bebound by single-system vendors of proprietaryequipment.C. Networking3G are based on primarily a wide-area concept. We needhybrid networks that utilize both wireless LAN (hot spot)concept and cell or base-station WAN design. With 4G,the world would have base stations everywhere, ensuringphone usersconnection to a high-speed networkanywhere, anytime.D. BandwidthWe need wider bandwidth and higher bit rates. The 4Gtechnology, with its transmission speeds of more than 20mbps, would offer high-bandwidth services within thereach of LAN "hotspots," installed in offices,homes,coffee shops,and airport lounges. Away from thesehotspots, customers could connect to souped-up 2Gnetworks for voice and rudimentary data coverage.E. TechnologyUnlike 3G, 4G will more resemble a conglomeration ofexisting technologies rather than an entirely newstandard. Analysts define 4G as a seamless combinationof existing 2G wireless networks with local-areanetworks (LANs) or Bluetooth.F. ConvergenceConvergence involves more than mere technology; it is acoming together of services and markets.We need allnetwork that utilizes IP in its fullest form with convergedvoice and data capability,which the 4G will achieve.G. Cost4G systems will prove far cheaper than 3G, since theycan be built atop existing networks and won't requireoperators to completely retool and won't require carriersto purchase costly extra spectrum.Also an open systemIP wireless environment would probably further reducescosts for service providers by ushering in an era of realequipment interoperability.H. ScalabilityScalability, or the ability to handle increasing numbers ofusers and diversity of services, is more challenging withmobile networks."Design for Scalability," includesinformation that can help you meet changing usagedemands.Because an all IP core layer of 4G is easilyscalable, it is ideally suited to meet this challenge.III.EVOLUTION AND COMPARISON OFBROADBANDWIRELESS1) First Generation (1G):1G wireless mobilecommunication systems, was introduced in the early1980s.1G wireless was analog and supported the firstgeneration of analog cell phones.They include asignaling protocol known as SS7 (Signaling System 7).2) Second Generation (2G): 2G systems, fielded in thelate 1980s, were intended primarily for voicetransmission and was all about digital PCS.3) Third Generation (3G): 3G in wireless will be adeliberate migration to faster, data-centric wirelessnetworks.The immediate goal is to raise transmissionspeeds from 125kbps to 2M bit/sec.4) Fourth Generation (4G): In reality, as of first half of2002, 4G is a conceptual framework for or a discussionpoint to address future needs of a universal high speedwireless network that will interface with wirelinebackbone network seamlessly.IV. THE 4G NETWORK THAT THECELL-HEADSDREAM ABOUT4G can be imagined of as an integrated wireless systemthat enables seamless roaming between technologies.Auser can be operating in cellular technology network andget handed over to a satellite-based network and back to afixed wireless network, depending upon the networkcoverage and preference of charging.A. The GoalsOpen Mobile Alliance’s (OMA) main goal is to makesure different wireless services and devices worktogether, and across countries, operators, and mobileterminals.Other plans in the group's charter include:•Deliver open standards and specifications based onmarket and customer requirements.• Create and promote a common industry view on anarchitectural framework.• Help consolidate standards groups and work inconjunction with other existing standardsorganizations and groups.B. The Composite Vision• 20 Mbps data rates• Streaming Audio/Video• Asymmetric Access• Adaptive Modulation/Coding• Dynamic packet assignment• Smart/Adaptive antennas supportedC. 4G Network Architecture“4G” wireless networks can be realized with an IP-basedcore network for global routing along with morecustomized local-area radio access networks that supportfeatures such as dynamic handoff and ad-hoc routing aswell as newer requirements such as self-organization,QoS, multicasting, content caching, etc..In 4G LANs will be installed in trains and trucks as wellas buildings, or even just formed on an ad-hoc basisbetween random collections of devices that happen tocome within radio range of one other. Routing in suchnetworks will depend on new architectures, already underdevelopment by the IEEE and a European project calledMobile IP Network Developments (MIND).D. The working PrincipleIn 4G-style mobile IP, each cell phone is assigned apermanent "home" IP address, along with a "care-of"address that represents its actual location.When acomputer somewhere on the Internet wants tocommunicate with the cell phone, it first sends apacketto the phone's home address.A directory server on thehome network forwards this to the care-of address via atunnel, as in regular mobile IP. However, the directoryserver also sends a message to the computer informing itof the correct care-of address, so future packets can besent directly.This should enable TCP sessions and HTTPdownloads to be maintained as users move betweendifferent types of networks.Because of the manyaddresses and the multiple layers of subnetting, IPv6 isneeded for this type of mobility.V. TECHNOLOGIES THAT SUPPORT 4GThe revolution in 4G will be the optical networking, thenew air interface, the portable device etc.A. The Transmission Protocols1) OFDM: OFDM is a digital modulation technology inwhich in one time symbol waveform, thousands oforthogonal waves are multiplexed.This is good for highbandwidth digital data transition.2) W-OFDM: W-OFDM enables data to be encoded onmultiple high-speed radio frequencies concurrently. Thisallows for greater security, increased amounts of databeing sent, and the industry’s most efficient use ofbandwidth.W-OFDM enables the implementation of lowpower multipoint RF networks that minimize interferencewith adjacent networks.This enables independentchannels to operate within the same band allowingmultipoint networks and point-to-point backbone systemsto be overlaid in the same frequency band.3) MC-CDMA : MC-CDMA is actually OFDM with aCDMA overlay.Similar to single-carrier CDMA systems,the users are multiplexed with orthogonal codes todistinguish users in (multi-carrier) MC-CDMA.Howeverin MC-CDMA, each user can be allocated several codes,where the data is spread in time or frequency.4) LAS-CDMA:LinkAir Communications is developer of LAS-CDMA(Large Area Synchronized Code Division MultipleAccess) a patented 4G wireless technology. LAS-CDMAenables high-speed data and increases voice capacity andlatest innovative solution, CDD, merges the highlyspectral efficient LAS-CDMA technology with thesuperior data transmission characteristics of TDD.Thisresulting combination makes CDD the most spectrallyefficient, high-capacity duplexing system available today.B. The Radio Interface-UWB RadioTo make 4G really work carries will need to migrate toUltra Wideband (UWB) technology.UWB radiowill deliver essential new wireless andwired bandwidth inexpensively, without using preciousand scarce radio frequencies.Instead,digital video, voiceand data are enabled using modulated pulses of energythat peacefully co-exist alongside traditionalcommunications.UWB radio solves the multipath fadingissues and is 1,000% more process efficient than CDMA.C. The Network-LMDSLocal multipoint distribution system (LMDS) is thebroadband wireless technology used to deliver voice,data, Internet, and video services in the 25-GHz andhigher spectrum (depending on licensing).The acronymLMDS is derived from the following: L(local)—denotes that propagation characteristics ofsignals in this frequency range limit the potentialcoverage area of a single cell site;M (multipoint)—indicates that signals are transmitted ina point-to-multipoint or broadcast method;D (distribution)—refers to the distribution of signals,which may consist of simultaneous voice, data, Internet,and video traffic;S (service)—implies the subscriber nature of therelationship between the operator and the customer.VI. POTENTIAL APPLICATIONS OF 4G1) Virtual Presence: 4G system gives mobile users a"virtual presence" -- for example, always-on connectionsthat keep people involved in business activities regardlessof whether they are on-site or off.2)Virtual navigation:A remote database contains thegraphical representation of streets, buildings, andphysical characteristics of a large metropolis.Blocks ofthis database are transmitted in rapid sequence to avehicle, where a rendering program permits the occupantsto visualize the environment ahead.3) Tele-medicine: 4G will support remote healthmonitoring of patients.For e.g. the paramedic assistingthe victim of traffic accident in a remote location mustaccess medical records and may need videoconferenceassistance from a surgeon for an emergency intervention.The paramedic may need to relay back to the hospital thevictim's x-rays taken locally.4)Tele-geoprocessing applications:Thecombination of geographical information systems (GIS),global positioning systems (GPS), and high-capacitywireless mobile systems will enable a new type ofapplication referred to as tele-geoprocessing.Queriesdependent on location information of several users, inaddition to temporal aspects have many applications.5) Crisis-management applications:Naturaldisasters can affect the entire communicationsinfrastructure is in disarray.Restoring communicationsquickly is essential.With wideband wireless mobilecommunications Internet and video services, could be setup in hours instead of days or even weeks required forrestoration of wireline communications.6) Education :Educational opportunities availableon the internet, for individuals interested in life-longeducation, will be unavailable to client in remote areasbecause of the economic unfeasibility of providingwideband wireline internet access.4G wirelesscommunications provides a cost-effective alternative inthese situations.VII. ROLE OF THE WIRELESSINDUSTRYRECOMMENDATIONSWe are bringing to the attention of professionalsfollowing issues and problems that must be analyzed andresolved:1)Standardization: Standardization of wireless networksin terms of modulation techniques, switching schemesand roaming is an absolute necessity for 4G. We mustpay more attention to general meaning advancedtechnologies.2) Lower Price Points Only Slightly Higher thanAlternatives: The business visionaries should do someeconomic modeling before they start 4G hype. Theyshould understand that 4G data applications likestreaming video must compete with very low costwireline applications.3) More Coordination Among Spectrum RegulatorsAround the World:We must demand almost freespectrum NOT necessarily unlicensed Spectrumregulation bodies must get involved in guiding theresearchers by indicating which frequency band might beused for 4G.4) Regulatory frameworks:Policy and RegulatoryEnvironment which Provides Transparency, Certaintyand a Level Playing Field are necessary. The mostimportant thing is that we should recognize thatregulatory framework is as much an evolving matter astechnology, and be prepared to meet changes with anopen-minded and pragmatic attitude, always keeping theinterests of the industry and consumers in mind.5) More Academic Research:Universities must spendmore effort in solving fundamental problems in radiocommunications (especially multiband and widebandradios, intelligent antennas and signal processing).6) Voice-independent Business Justification Thinking:Business and Technology executives should not bias theirbusiness models by using voice channels as economicdeterminant for data applications.V oice has a built-indemand limit - data applications do not.7) Integration Across Different Network Topologies:Network architects must base their architecture on hybridnetwork concepts thatintegrates wireless wide areanetworks, wireless LANS (IEEE 802.11a, IEEE 802.11b,IEEE 802.11g, IEEE 802.15 and IEEE 802.16), Bluetoothwith fiber-based Internet backbone.Broadband wirelessnetworks must be a part of this integrated networkarchitecture.8) Non-disruptive Implementation: Upgrading from 3G to 4G is expected to be seamless to end-users with nodevice upgrades required.VIII. DEVELOPMENTS IN 4GAT&T is combining W-OFDM and EDGE technologies,to provide broadband mobile downlink access at peakrates of up to 10 Mbps while EDGE offers uplink accessat 384 Kbps with an 800KHz bandwidth in a high-mobilityenvironment.Sun Microsystems Laboratories are building 4G wirelesstechnologies that promise tointegrate voice and web datain an IP-based mobile communications.The Government of Karnataka in India has signed a MoUwith Charmed Technologies Inc from Beverly Hills,California and Software Technology Parks of India inKarnataka to develop 4G wireless technology. Theproject plan to use wireless technology based on theIEEE802.11a and IEEE802.11b standards for wirelessLAN for the underlying network is designed to support adata rate of up to 11Mbps and 54Mbps respectively. Thegoal is to get 6 billion people connected to the wirelessInternet by 2010.NTT DoCoMo and Hewlett-Packard Company &MOTOmediacollaboration will explore new mobile serviceconcepts in which people, places and things will be ableto interact, thereby bridging the real and the cyber world.MOTO-media is expected to enable high performancestreaming of multimedia content to mobile users.DoCoMo and HP aim to nish the shared study of basictechnology by 2003 and hope to push for 4G in 2006.IX. SUGGESTIONSWe would like to give the following suggestions for thedevelopment of 4G mobile technologies:1. Technologies like 4G must be developed to integrateinto a more flexible network that grow within thenetwork so that we don't have to scarp the old network toimplement the next generation, the generations to come.2. The very big challenge for developing a technology isproper human resource for building high quality systems.Big organization, which is engaged in software andsystem development, should rapidly go for tie-ups witheducational institutes for better manpower and knowledgemanagement.3. We talk about mobile multimedia that 4G will supportbut in reality people are not going to watch TV whilethey walk down the street. Likewise people will not buyCoca Cola at vending machines with a cell phone. Quitoften services conjured up by the engineering side of thevendor organizations has little to do with the reality. Sowireless industry should ponder well about marketdemand and invest money so that they will not be at loss.X.CONCLUSION4G should make a significant difference and addperceived benefit to an ordinary person’s life over 3G.We should drop the 2.5G, 3G, 4G speak altogether wherean additional “G” means merely an increase in capacity.What really means something for the users are newservices, integration of services, applications etc. Ourgoal is to struggle to get a “G”eneration of standards sothat we can take our phone anywhere in the world andaccess any service or communicate with any other userany way we want that will offer connectivity soinexpensively. In short, 4G or WWWW (World WideWireless web) should be a more intelligent technologythat interconnects the entire world without limits.二、英文翻译:下一代无线宽带的目标(4G—5G)摘要:随着接入技术的增长,语音、视频、多媒体和宽带数据业务正在集成到同一个网络中去。
通信与信息工程专业英语教程词汇翻译 陈杰美
analog 模拟digital 数字的binary-coded number 二进制编码数electromagnetic induction 电磁感应telegraph 电报triode vacuum tube 三级真空管broadcasting 广播amplitude modulation (AM)幅度调制frequency modulation (FM)频率调制phase modulation (PM) 相位调制transistor 晶体管linear integrated circuit 线性集成电路microwave 微波satellite 卫星optical fiber 光纤shortwave 短波negative-feedback amplifier 负反馈放大器PCM(Pulse-Code Modulation)脉冲编码调制time-division multiplexing (TDM)时分多路stereo FM 立体声调频error-correction code 纠错编码adaptive equalization 自适应均衡random access memory (RAM)随机存取存储器VLSI(very large scale integration)超大规模集成FAX (facsimile) 传真cellular telephone 蜂窝电话移动电话oscilloscope 示波器spread spectrum system 扩频系统ISDN(integrated services digital network)综合业务数字网HDTV(high definition television)高清晰度电视transmitter 发射机channel 信道频道通道receiver 接收机baseband 基带bandwidth (BW)频带宽度带宽ADC(analog-digital converter)模数变换器carrier 载波载流子bandpass signal 带通信号signal sideband (SSB)单边带phase-shift keying(PSK)相移键控ITU(international telecommunications union)国际电信联盟PTN(public telecommunications network)公用电信网络LOS propagation 视线传播ionospheric reflection 电离层反射high fidelity (Hi-Fi)高保真度signal-to-noise 信噪比interference 干扰mapping 映射dimension 维数量纲frequency selectivity 频率选择性photocathode 光电阴极raster scanning 光栅扫描blanking pulse 消隐脉冲multiplexer 多路转换器encoder 编码器decoder 译码器pixel 像素vocal tract filter 声道滤波器melodic structure 韵律结构harmonic structure 谐波结构interlaced fields 交替的场horizontal retrace 水平行回程primary colors 基色interactive video 交互式视频ASCII 美国标准信息交换码DCT (discrete cosine transform)离散余弦变换JPEG (joint photographic experts group)联合图像专家组MPEG(motion photographic experts group)) 活动图像专家组synchronous transmission 同步传输asynchronous transmission 异步传输frame 帧frame-packing 成帧modeling 建模Fourier series(FS) 傅里叶级数transmission medium 传输介质coaxial cable 同轴电缆instantaneous power 瞬时功率decibel 分贝dBRF(radio frequency)射频commutator 换向器转接器ripple 波纹起伏ionosphere 电离层potential difference 电位差shot noise 散弹噪声flicker noise 闪变噪声noise figure 噪声系数mathematic model 数学模型rms value 均方根值orthogonal series 正交系数power density spectrum 功率谱密度common logarithm 以10为底的对数DC power supply 直流电源AC ripple 交流波纹AM receiver 调幅接收机thermal noise 热噪声root-mean-square(rms)alternating current (AC) 交流direct current (DC) 直流cable television (CATV)有线电视field-effect transistor (FET)场效应晶体管bipolar junction transistor(BJT)晶体三极管inductor coil 电感线圈inductor 电感器rating power 额定功率capacitor 电容器quality factor 品质因数piezoelectric crystal 压电晶体inductive reactance 感抗capacitive reactance容抗susceptance 电纳mounting capacitance 安装电容impedance 阻抗notch filter 陷波式滤波器oscillator 振荡器flywheel effect 飞轮效应feedback 反馈loop gain 环路增益voltage gain 电压增益amplifier 放大器扩音器emitter 发射机base 基极collector 集电极inductive coupling 电感耦合radio-frequency choke (RFC)射频扼流圈junction capacitance 结电容integrated-circuit (IC)集成电路buffer amplifier 缓冲放大器chip 芯片frequency synthesizer 频率合成器energy dissipation 能耗tank circuit 槽路sinusoidal signal 正弦信号crystal oscillator 晶体振荡器monolithic chip 单片VHF(very high frequency) 甚高频UHF(ultra high frequency)超高频uncertainty 不确定性误差probability 概率几率autocorrelation 自相关函数covariance 协方差strict-sense stationary process 狭义平稳过程严平稳过程wide- sense stationary process 广义平稳过程宽平稳过程second-order process 二阶平稳过程infinity 无穷大ergodic process 各态遍历过程Gaussian process 高斯过程stochastic process 随机过程random signal 随机信号deterministic signal 确定信号argument function 被积函数joint probability distribution 联合概率分布statistical parameter 统计参数mathematical expectation 数学期望Gaussian white noise 高斯白噪声ensemble average 总体平均time average 时间平均correlation function 相关函数auto covariance 自协方差the first-order moment 一阶矩sample space 样本空间random variable 随机变量unbiased estimation 无偏估计normalized 归一化linear functional 线性泛函antenna 天线nonlinear 非线性的envelope 包络AM DSBFC 全载波的双边带调幅modulator 调制器class A amplifier (A)甲类放大器transformer 变压器double sideband (DSB)双边带AM envelope调幅包络carrier signal 载波信号voice-grade 话音级modulation coefficient 调制系数lower side band (LSB)下边带lower side frequency (LSF)上边频upper side band (USB)上边带upper side frequency (USF)上边频phasor 相量vector 矢量nonlinear mixing非线性混频frequency domain 频域coupling capacitor 耦合电容final stage 末级(电路)modulating signal 调制信号modulated wave 已调波emitter modulator 发射机调制器DSB AM 双边带幅度调制transistorized transmission 晶体管化发射机unitless 无量纲的lo-level modulator 低电平调制器modulation 调制过程modulator 实现调制的电路modulating signal 调制信号demodulation 在接收端从已调波中恢复调制信号的过程demodulator 解调器duplicate 复制品,副本inversion 倒置elimination 消除canonical 规范的quadrature 正交discrimination 辨别,区别,识别力nonoverlapping 不相重叠的resonator 谐振器,振荡器simultaneous 同时的,同时发生的subsequent 后来的,并发的reinforcement 增援,加强,加固junction 连接,交叉点prescribe 指示,规定cutoff 截止,切掉coherent 相干的,一致的locally 在本地undergo 经历,遭受,忍受difference 差分,差别angle modulation 角度调制complex envelop 复包络proportional 比例量,成比例的intergral 积分,综合deviation constant 偏移常数subscript 下标的integrator 积分器,综合者cascade 串联,级联instantaneous 瞬间的,即刻的frequency deviation 频率偏移nonnegative 非负的正的peak-to-peak deviation 峰峰偏移phase modulation index 调相指数frequency modulation index 调频指数sinusoida 正弦的superposition 重叠,叠加原理approximation 接近,近似值sideband 边带multiplier 乘数,乘法器narrowband frequency modulation(NBFM)窄带频率调制wideband frequency modulation(WBFM)宽带频率调制frequency multiplication 倍频limiter 限幅器voltage-controlled-oscillator( V OC)压控振荡器incorporate合并混合PLL(phase locked loop) 锁相环frequency divider 分频器tolerance 耐性容限power spectral density(PSD)功率谱密度probability density function(PDF)概率密度函数intuitive直觉的viewpoint 观点emphasis加重preemphasis 预加重deemphasis去加重boost升压,attenuate 减弱信号,衰减longitudinalpotential位差,势差balun 巴伦,平衡—不平衡变压器electrostatic shield 静电屏蔽ribbon cable 带状传输线coaxial cable 同轴电缆open-wire 明线insulated 绝缘的,隔热的sheath 阳极,屏极stray capacitance 寄生电容杂散电容spacer 逆电流器dielectric 电介质绝缘体susceptible 易受影响的pick-up 获得polyethylene聚乙烯permittivity 介电常数reflectometry反射计impairment 损害,损伤echo 回声,回波prependicular 垂直的transponder 微型转发器vacuum 真空encounter 遭遇遇到infrared 红外线ultraviolet 紫外线refraction 折射diffract 衍射interference 干涉collide 碰撞penetrate 穿透渗透curve 曲线弯曲diffuse 漫射散开redistribution 重新分配opaque 不透明物phenomenon 现象wavelet小波finite 有限的simultaneously同时的polarization偏振极化negligible可以忽略的conductivity 传导性传导率induce感应navigation导航curvature曲率troposphere对流层ionize电离molecule 分子exert 施加vibrate 震动equivalent相当的ionization离子化nonuniform不均匀的stratified分层的parabolic抛物线的focal焦点resonance谐振共振dipole双极子偶极子mast天线竿triode 三极真空管klystron调速管magnetron磁控管radiotelephone 无线电话elliptically椭圆形的feedpoint馈点isotropic等方性的reciproal互易的beamwidth波束宽度omnidirectional全方向的parasitic寄生的concave凹的inphase同相的reradiated在辐射convergent汇聚性的convex凸的broadside侧面的crisscross十字形交叉power splitter 功率分配器dielectric电介质绝缘体boundary边界photophone光电话impurity杂质混杂物megabit百万兆位dispersion色散pulsing脉冲调制repester转发器regenerator再生器photodetector光电探测器threshold阀值,门限timing时序thermoelectric电热的splic接合cooler冷却器packaging封装adapter适配器jumper跳线overload超过负荷multiplexer多路复用器demultiplexer多路信号分离器doped 掺杂质的very large integration(VLSI)超大规模集成电路digital signal processing(DSP)数字信号处理noise immunity抗干扰度encryption加密programmable可编程的multipath and fading多径衰减power efficiency功率效率bandwidth efficiency带宽效率fidelity保真度pulse-width 脉冲宽度throughput吞吐量non-fading channel无衰落信道multimum-shift-keyed(MSK)最小位移键控on-off keying(OOK)开关键控unipolar 单极性的binary phase-shift keying(BPSK)二进制相移键控mark frequency传号频率space frequency空号频率premodulation预调制cosine-rolloff filter余弦滚降滤波器pilot carrier导频载波digital modulation index数字调制指数null-to-null bandwidth零点-零点带宽coherent相干检波ambiguity含糊differential差分编码integrate-and-dump matched filter积分清楚匹配滤波器digital-to-analog converter(DAC) 数模转换器offset 偏移量wavelength-division multiplexing(WDM)波分复用dense-WDM密集波分复用end-fire-array 端射阵phased array 相控阵inpedence matcher 阻抗匹配器erbium-doped fiber amplifiers 掺铒光纤放大器binary-coded 二进制编码的mainframe 主机,大型机interconnect 使互相连接information highway 信息高速公路indefinitely 不确定的facility 容易,便利,设备,工具secondary 次要的,二级的,第二的peripheral 外围的,外围设备data terminal equipment(DTE) 数据终端设备data conmunications equipment(DCE)数据通信设备vice versa 反之亦然serial 串行的parallel 并行的host主机topology 拓扑,布局,mesh 网孔,网套,陷阱citizens band 居民频带syntax 语法,句子结构interrogation 审问,问号American Standard Code for Information Interchange (ASCII) 美国信息交换标准码Extended Binary-Code Decimal Interchange Code (EBCDIC) 扩充的二-十进制交换码teletype code 电传打字机电码least significant bit(LSB) 最低有效位most significant bit(MSB) 最高有效位partity 同等,平等,奇偶校验error control 差错控制error detection 检错error correction 纠错echoplex 回送checksum 校验和cyclic redundancy checking(CRC) 循环冗余检查backspace 退后一格,退格erroneous 错误的,不正确的circuitry 电线,线路hex 十六进制polynomial 多项式的symbol substitution 符号替换selective retransmission 选择性重传forward error correction 前向纠错ingtegrity 正直,诚实,完整性turnaround 回车场,转变,转向prior 在先,居先Hamming code 汉明码electronic mail 电子邮件handset 电话听筒,手机,手持机cellular phone 便携式电话,移动电话set-top TV box 电视机顶盒telephony 电话学,电话技术conversation 会话,交谈circuit switching 电路交换mechanical 机械的,呆板的bit stream 位流,比特流interface 分界面,界面,接口instruction 指令common channel signaling 公共信道信令trunk 干线中继线路subscriber telephone 电话用户digital carrier system 数字载波系统accommodate 供应,调节,调和deviate 异化,越轨,偏离nominal 名义上得Integrated Services Digital Network(ISDN)综合业务数字网bidirectional 双向的full-duplex 全双工的facsimile 摹写,传真remote monitoring 远程监控videotext 可视图文videophone 可视电话attenuation 变薄,变细,衰减Asymmetric Digital Subscriber Line(ADSL)非对称用户数字线protocol 草案,协议character at a time 每次传送一个字符cross-talk 他处传来的干扰,串话severe 严厉的,剧烈的,严重的modem 调制解调器synchronous transmission 同步传输SDLC(Synchronous Data Link Control)同步数据链路控制HDLC(High-Level Data Link Control)高级数据链路控制LAPB 平衡型链路访问规程packet 包装,信息包preamble 前言,序,前导信号self-synchronizing code 自同步码store-and-forward packet-switching存储转发分组交换point-to-point 点对点intermittent 间歇的,断断续续的statistical multiplexing 统计复用Ethernet 以太网Chip 碎片,芯片,筹码LAN(Local Area Network) 局域网,本地网WAN(Wide Area Network) 广域网Asynchronous Transfer Mode(ATM)异步传输模式cell 蜂窝,信源VCI 虚通路标识optical fiber 光纤cable television 有线电视,电缆电视Community Antenna Television(CATV)有线电视,公用天线电视obstruction 阻塞,妨碍,障碍物feeder 馈电线,电源线,连接线unidirectional 单向的,单向性的hybrid fiber/coaxial(HFC) 光缆与同轴电缆混合网fiber-to-the-curb(FTTC) 光纤到路边cable modem 电缆调制解调器nonadjacent 不临近的,不毗连的turn over 翻身,折腾,反复考虑Peer-to-Peer 对等网络wireline 有线线路toehold 排除障碍的方法notebook 笔记薄,笔记本palm-sized computer 掌上电脑backbone 脊椎,中枢,支柱,勇气terabit兆兆位Web 环球网bandwidth 带宽channel 信道,频道delay 延迟,时延hierarchy 层次结构pitch 音调substantially 充分的voiced 有声的,浊音的quasi-stationary 拟稳态的formant 共振峰,构形成分resonance 共鸣,回声,反响,谐振vocal track 声带vocoder 声码器VF(V oice Frequency) 话音频率adaptive subband coding 自适应自带编码vector quantization 矢量量化code excited linear prediction 码激励线性预测vector-sum excited linear prediction矢量和激励线性预测analysis-by-synthesis technique 分析合成技术codebook 码本best match 最佳匹配codec 多媒体数字信号编解码器probability distribution 概率分布autocorrelation 自相关successive 继承的,连续的unvoiced清音的quasiperiodicity 准周期性bandlimited 带限的time-discietized 时间离散化reconstruct 重建,改造,推想monotonically decreasing function 单调递减函数exponential 指数的,幂数的Gaussian distribution 高斯分布,正态分布variance 方差manifestation 显示,表现,示威运动coding gain 编码增益spectral flatness measure(SFM)谱平坦性测度geometric mean 几何平均redundancy冗余cordless 不用电线的,无绳preferentially 优待的perception 理解,感知,感觉harmonic 谐和的,和声的,谐波,谐函数sub-band coding(SBC) 子带编码block transform coding 块变换编码bandpass 带通band-splitting 子带分解articulation index 传声准率portion 一部分,一分in tune 和调子convolution 卷积,卷积积分multiplex 多路传输,多路复用alias 混淆,折叠quadrature mirror filters(QMF) 正交镜像滤波器latecy 等待时间,延迟cellular telephone system 蜂窝(移动)电话系统performance 性能,能力signal-to-noise radio 信噪比mean square error(MSE) 均方误差weighted 加权的diagnostic rhyme test(DRT) 押韵诊断测试diagnostic acceptability measure(DAM)接受能力诊断测试mean opinion score(MOS)平均主观评分inherently 天地性,固有性spectrum 频谱utilization 利用intrastate 周内的haul 托运距离noncoherent 非相干的simultaneously 同时的deviator 偏差器,致偏器scheme 安排,配置,计划,方案uniform 统一的,相同的,一致的,均衡的eventually 最后,终于mixer 混频器heterodyning 外差法,外差作用demodulator 解调器convey 搬运传达destination 目的地phenomenal 显著的telemetry 遥感勘测,自动测量记录传导diminishing 逐渐缩小的accommodate 供给,容纳investigate 调查,研究avenue 方法途径prohibitive 禁止的,抑制的adequate 适当的,足够的quantize 使量子化,量化discrete 不连续的,离散的aptly 适当的,适宜的lean 倾向,偏向designator 指示者,指定者so-called 所谓的,号称的astronomical 天文学的,天文celestial body 天体payload 有效载荷military 军事的,军用的subscriber 订户,签署者geostationary 与地球的相对位置之不变的aeronautical 航空学的roughly 概略的obstacle 障碍,障碍物govern 统治,支配constituent 要素hub 网络集线器,网络中心margin 极限,富余architecture 体系结构platform 平台cruise 巡航gateway 网关altenatively 作为选择,二者选一overlap 与..交叠implement 实现,执行hybrid 混合的latitude 纬度,地区guarantee 保证,担保nowadays 现今,现在sophisticated 高度发展的,精密复杂的coordinate 协调,调整,整理equatorial 近赤道的,赤道的distributed 分布式的stationary 固定的deploy 配置isotropic各向同性的specialise 专门研究,深入miche 放在适当的位置marketability 可销售性crosspolarization 交叉极化furthermore 此外,而且critical 紧要的,关键性的,临界的majority 多数,大半degrading 丧失体面的,可耻的,不名誉的coding 编码intermediate 中间的alongside 并排地regulate 管制,控制budget 预算degrade 降低,降级,退化compensate 补偿,付报酬subdivide 再分,细分feasible 切实可行的burst 突发,脉冲periodic 周期的,定期的synchronize 同步recovery 恢复expansion 扩充,扩展vital 至关重要的,必须得preassign 预先指定,预先分配reservation 预定,预约dynamic 动态的eliminate 消除,去除uncoordinated 不协调的collision 碰撞,冲突implementation 执行,实现retransmission 重发,转播optimal 最佳的,最理想的corresponding 相应的yielding 出产,生长,生产incremental 增加的magnitude 大小,数量,模algorithm 算法encoding 编码concatenation 串联,连锁node 节点tolerant 容许的literally 逐字的antijam 抗干扰contiguous 临近的,邻接的authentication 证明,鉴定adequately 充分的eavesdropper 偷听者pseudorandom 伪随机的simultaneously 同时的excel优秀penalty 损失unpredictable 不可预知的correlation 相互关系,相关性clutter混乱mobile telephone service 移动电话业务monster 怪物,妖怪,巨人methodology 一套方法provoke 激怒,挑拨,煽动,驱使regardless 不管,不顾terminology 术语学transceiver 无线电收发机,收发器pedestrian 步行者,徒步的,通俗的base station 基站scramble 扰频municipal 市政的,地方自治的trunking 中继census 人口普查hexagonal 六角形,六边形的honeycomb 蜂巢,蜂窝in accordance with 与..一致,依照macrocell 宏单元,宏小区radius 半径,范围,界限microcell 微小区virtue 德行,美德,贞操,优点,功效,效力mild 温和的,温柔的,适度的overlay 覆盖,microcellular 微小区intriguing 迷人的,有迷惑力的infrastructure 下部结构,基础组织splitting 分裂,裂解sector 使分成部分,扇形扫描overhead 在头上的,高架的handoff 手递手传递,移交metropolitan 首都的,大城市United States Digital Cellular(USDC)美国数字蜂窝系统compatible 谐调的,一致的,兼容的reuse 再使用time-division multiple accessing(TDMA)时分多址time slot 时间空档,时隙geographical 地理学得,地理的interleaving 交叉,交错threeflod 三倍encrypt 加密decrypt 解释明白,解密safeguard 维护,捍卫,eavesdropping 偷听channelization通信波道的选择coed-division multiple accession(CDMA) 码分多址Pilot 飞行员differentiate 区分,区别,微分spread-spectrum 扩频coherent 黏在一起的,相干的graceful 优美的,雅致的,适度的real time 实时asynchronous 不同时的,异步的重点词汇。
信息与通信工程专业科技英语翻译10
X. Third Generation Wireless Networks第三代无线网络移动通信简介电信工业面临着向用户稀少而安装固定电话网络成本很高的乡间地区提供电话服务的问题。
降低有线电话高昂基础设施费用的一个方法是使用固定无线电网络。
这一方面存在的问题是,对于乡间和城市需要由大的蜂窝单元以达到足够的覆盖。
而且由于多径传播的长时间延迟又遇到额外的问题。
目前在澳大利亚全球移动通信系统(GSM)技术正被用于农村地区的固定无线电话系统。
然而GSM使用时分复用(TDMA),这种技术的符号速率很高,会导致多径引起码间干扰的问题。
人们正在考虑用于下一代数字电话系统的好几种技术,目的是改进蜂窝单元的容量、抗多径干扰以及灵活性。
这些技术包括CDMA和COFDM,这两者都能用于向农村提供固定无线系统。
不过每一种技术有不同的性质,分别适用于特定的应用。
COFDM目前正用于一些新的无线广播系统包括高清晰度电视(HDTV)提案和数字音频广播(DAB),而对COFDM作为一种移动通信系统的传输方法却研究甚少。
在CDMA中所有用户在同一频带中传输,他们用特殊的码实现信道化。
基站和移动站都知道用于调制发送数据的码。
OFDM/COFDM通过将可用带宽分成许多窄带载波使许多用户能在给定的频带内发送信号。
每个用户分配到若干载波在其中发送数据。
传输以这样的方法进行:载波之间相互正交因而它们可以被安排得比标准得频分复用(FDM)拥挤得多,这就使OFDM/COFDM有很高的频谱使用效率。
第三代无线网络数字网络使用的扩展已经导致了设计大容量通信网络的需要。
在欧洲,蜂窝型系统到2000年的需求预计将达到1500至2000万户,而美国(1995年)已经超过了3000万户。
无线通信服务正以每年50%的速度增长,目前的第二代欧洲数字系统(GSM)预期在21世纪初达到饱和。
随着广泛的业务需求如视频会议、互联网服务、数据网络、多媒体等的发展,电信工业也在变化之中。
通信工程专业英语名词缩写
电子类常用缩写(英文翻译)AC(alternating current) 交流(电)A/D(analog to digital) 模拟/数字转换ADC(analog to digital convertor) 模拟/数字转换器ADM(adaptive delta modulation) 自适应增量调制ADPCM(adaptive differential pulse code modulation) 自适应差分脉冲编码调制ALU(arithmetic logic unit) 算术逻辑单元ASCII(American standard code for information interchange) 美国信息交换标准码AV(audio visual) 声视,视听BCD(binary coded decimal) 二进制编码的十进制数BCR(bi-directional controlled rectifier)双向晶闸管BCR(buffer courtier reset) 缓冲计数器BZ(buzzer) 蜂鸣器,蜂音器C(capacitance,capacitor) 电容量,电容器CATV(cable television) 电缆电视CCD(charge-coupled device) 电荷耦合器件CCTV(closed-circuit television) 闭路电视CMOS(complementary) 互补MOSCPU(central processing unit)中央处理单元CS(control signal) 控制信号D(diode) 二极管DAST(direct analog store technology) 直接模拟存储技术DC(direct current) 直流DIP(dual in-line package) 双列直插封装DP(dial pulse) 拨号脉冲DRAM(dynamic random access memory) 动态随机存储器DTL(diode-transistor logic) 二极管晶体管逻辑DUT(device under test) 被测器件DVM(digital voltmeter) 数字电压表ECG(electrocardiograph) 心电图ECL(emitter coupled logic) 射极耦合逻辑EDI(electronic data interchange) 电子数据交换EIA(Electronic Industries Association) 电子工业联合会EOC(end of conversion) 转换结束EPROM(erasable programmable read only memory) 可擦可编程只读存储器EEPROM(electrically EPROM) 电可擦可编程只读存储器ESD(electro-static discharge) 静电放电FET(field-effect transistor) 场效应晶体管FS(full scale) 满量程F/V(frequency to voltage convertor) 频率/电压转换FM(frequency modulation) 调频FSK(frequency shift keying) 频移键控FSM(field strength meter) 场强计FST(fast switching shyster) 快速晶闸管FT(fixed time) 固定时间FU(fuse unit) 保险丝装置FWD(forward) 正向的GAL(generic array logic) 通用阵列逻辑GND(ground) 接地,地线GTO(Sate turn off thruster) 门极可关断晶体管HART(highway addressable remote transducer) 可寻址远程传感器数据公路HCMOS(high density COMS) 高密度互补金属氧化物半导体(器件)HF(high frequency) 高频HTL(high threshold logic) 高阈值逻辑电路HTS(heat temperature sensor) 热温度传感器IC(integrated circuit) 集成电路ID(international data) 国际数据IGBT(insulated gate bipolar transistor) 绝缘栅双极型晶体管IGFET(insulated gate field effect transistor) 绝缘栅场效应晶体管I/O(input/output) 输入/输出I/V(current to voltage convertor) 电流-电压变换器IPM(incidental phase modulation) 附带的相位调制IPM(intelligent power module) 智能功率模块IR(infrared radiation) 红外辐射IRQ(interrupt request) 中断请求JFET(junction field effect transistor) 结型场效应晶体管LAS(light activated switch)光敏开关LASCS(light activated silicon controlled switch) 光控可控硅开关LCD(liquid crystal display) 液晶显示器LDR(light dependent resistor) 光敏电阻LED(light emitting diode) 发光二极管LRC(longitudinal redundancy check) 纵向冗余(码)校验LSB(least significant bit) 最低有效位LSI(1arge scale integration) 大规模集成电路M(motor) 电动机MCT(MOS controlled gyrator) 场控晶闸管MIC(microphone) 话筒,微音器,麦克风min(minute) 分MOS(metal oxide semiconductor)金属氧化物半导体MOSFET(metal oxide semiconductor FET) 金属氧化物半导体场效应晶体管N(negative) 负NMOS(N-channel metal oxide semiconductor FET) N沟道MOSFET NTC(negative temperature coefficient) 负温度系数OC(over current) 过电流OCB(overload circuit breaker) 过载断路器OCS(optical communication system) 光通讯系统OR(type of logic circuit) 或逻辑电路OV(over voltage) 过电压P(pressure) 压力FAM(pulse amplitude modulation) 脉冲幅度调制PC(pulse code) 脉冲码PCM(pulse code modulation) 脉冲编码调制PDM(pulse duration modulation) 脉冲宽度调制PF(power factor) 功率因数PFM(pulse frequency modulation) 脉冲频率调制PG(pulse generator) 脉冲发生器PGM(programmable) 编程信号PI(proportional-integral(controller)) 比例积分(控制器)PID(proportional-integral-differential(controller))比例积分微分(控制器) PIN(positive intrinsic-negative) 光电二极管PIO(parallel input output) 并行输入输出PLD(phase-locked detector) 同相检波PLD(phase-locked discriminator) 锁相解调器PLL(phase-locked loop) 锁相环路PMOS(P-channel metal oxide semiconductor FET) P沟道MOSFETP-P(peak-to-peak) 峰--峰PPM(pulse phase modulation) 脉冲相位洲制PRD(piezoelectric radiation detector) 热电辐射控测器PROM(programmable read only memory) 可编只读程存储器PRT(platinum resistance thermometer) 铂电阻温度计PRT(pulse recurrent time) 脉冲周期时间PUT(programmable unijunction transistor) 可编程单结晶体管PWM(pulse width modulation) 脉宽调制R(resistance,resistor) 电阻,电阻器RAM(random access memory) 随机存储器RCT(reverse conducting thyristor) 逆导晶闸管REF(reference) 参考,基准REV(reverse) 反转R/F(radio frequency) 射频RGB(red/green/blue) 红绿蓝ROM(read only memory) 只读存储器RP(resistance potentiometer) 电位器RST(reset) 复位信号RT(resistor with inherent variability dependent) 热敏电阻RTD(resistance temperature detector) 电阻温度传感器RTL(resistor transistor logic) 电阻晶体管逻辑(电路)RV(resistor with inherent variability dependent on the voltage) 压敏电阻器SA(switching assembly) 开关组件SBS(silicon bi-directional switch) 硅双向开关,双向硅开关SCR(silicon controlled rectifier) 可控硅整流器SCS(safety control switch) 安全控制开关SCS(silicon controlled switch) 可控硅开关SCS(speed control system) 速度控制系统SCS(supply control system) 电源控制系统SG(spark gap) 放电器SIT(static induction transformer) 静电感应晶体管SITH(static induction thyristor) 静电感应晶闸管SP(shift pulse) 移位脉冲SPI(serial peripheral interface) 串行外围接口SR(sample realy,saturable reactor) 取样继电器,饱和电抗器SR(silicon rectifier) 硅整流器SRAM(static random access memory) 静态随机存储器SSR(solid-state relay) 固体继电器SSR(switching select repeater) 中断器开关选择器SSS(silicon symmetrical switch) 硅对称开关,双向可控硅SSW(synchro-switch) 同步开关ST(start) 启动ST(starter) 启动器STB(strobe) 闸门,选通脉冲T(transistor) 晶体管,晶闸管TACH(tachometer) 转速计,转速表TP(temperature probe) 温度传感器TRIAC(triodes AC switch) 三极管交流开关TTL(transistor-transistor logic) 晶体管一晶体管逻辑TV(television) 电视UART(universal asynchronous receiver transmitter) 通用异步收发器VCO(voltage controlled oscillator) 压控振荡器VD(video decoders) 视频译码器VDR(voltage dependent resistor) 压敏电阻VF(video frequency) 视频V/F(voltage-to-frequency) 电压/频率转换V/I(voltage to current convertor) 电压-电流变换器VM(voltmeter) 电压表VS(vacuum switch) 电子开关VT(visual telephone) 电视电话VT(video terminal) 视频终端。
通信工程专业英语课文翻译
Technology of Modern CommunicationText A: BluetoothBluetooth wireless technology is a short-range communications technology intended to replace the cables connecting portable(轻便的)and fixed devices while maintaining high levels of security.The key features of Bluetooth technology are robustness(稳健), low power, and low cost .The Bluetooth specification defines a uniform structure for a wide range of devices to connect and communicate with each other.蓝牙无线技术是一种小范围无线通信技术,旨在保持高安全级的基础上,在便携式设备与固定设备之间实现无线连接。
蓝牙技术的主要特点是稳健,低功耗和低成本。
蓝牙规范定义了一个统一的结构,适用范围广的设备连接并相互沟通。
Bluetooth technology has achieved global acceptance such that any Bluetooth enable device, almost everywhere in the world, can connect to other Bluetooth enabled devices in proximity. Bluetooth enabled electronic devices connect and communicate wirelessly through short-range, ad hoc(特别)networks known as piconets Each device can simultaneously communicate with up to seven other devices within a single piconet. Each device can also belong to several piconets simultaneously. Piconets are established dynamically and automatically as Bluetooth enabled devices enter and leave radio proximity.蓝牙技术已取得全球认可,使得任何支持蓝牙的设备,几乎在世界各地,可以连接到其他支持蓝牙的邻近装置。
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。
通信方面一些英语的翻译
通信工程专业课程Communication Engineering Specialty Course专业核心课程:The professional core courses:信息论及编码原理、通信原理、电视原理、电磁场及电磁波、天线及电波传播Information theory and coding theory, communication principle, the principle of television, electromagnetic field and electromagnetic wave, antenna and radio wave propagation广播电视发送方向:数字电视技术、广播电视发送技术、数字广播技术Radio and television transmission direction: digital television technology, radio and television transmission technology, digital broadcasting technology移动通信方向:移动通信、现代交换技术、移动电视技术Directions: mobile communication, mobile communication, mobile TV technology of modern switching technology信息论及编码原理:本课程着重介绍信源的类型及特性、信源熵、信道容量、信息率失真函数等信息论的基本理论,以及信源编码和信道编码的基本概念和主要方法。
这些信息论及编码的基本理论和方法不仅适用于通常意义的通信领域,如数字视音频处理和多媒体通信等,也适用于信息安全等计算机信息处理和管理等专门领域的需要。
Information theory and coding theory: This course mainly introduces the types and characteristics of information source, information entropy, channel capacity, information rate distortion function of information theory, as well as the source coding and channel coding of the basic concepts and main methods. The information theory and coding theory and method can be applied not only to the usual sense of the communication field, such as the processing of digital audio and video and multimedia communications, also applies to the information security of computer information processing and management of specialized areas of need.通信原理:本课程以当前广泛应用的通信系统和代表发展趋势的通信技术为背景,系统介绍数字通信基本原理,为学生今后从事相关工作提供理论基础和实际知识。
通信工程专业英语Unit 2:Digital Communication System
专业英语的翻译
省略:根据汉语语法的修辞习惯,将原文中的某些词语略 去不译。(如英语中的冠词、代词和连词)
Air is a fluid but not a liquid.
空气是流体, 不是液体。(省略冠词) If you know the frequency, you can find the wave length. 如果知道频率,就能求出波长。(泛指的人称代词you 可省略不译)
TEXT
The use of digital methods for the transmission of analog signals is becoming increasingly common in telecommunication systems. There are two major reasons for this. digital :数字的, 数位的
Specialized English for Communication Engineering
专业英语的翻译
句子结构上有差异 词汇上很少对等
English
Chinese
死译 硬译 直译:基本上保留原文的表达形式及内容,不做大的改 动,同时译出的文字又明白易懂; 胡译 意译:在正确理解原意的基础上,重新遣词造句,把原 文的意思用通顺的汉语表达出来。
The reliability can be further improved by using errordetecting and error-correcting codes.
利用检错和纠错编码能进一步提高可靠性。(被动语态 转译为主动语态) Specialized English for Communication Engineering
通信工程专业英语
一、汉译英1、时分多址:TDMA (Time Division Multiple Address/ Time Division Multiple Access)2、通用无线分组业务:GPRSGeneral Packet Radio Service3、国际电报电话咨询委员会:CCITT4、同步数字体系:SDH Synchronous Digital Hierarchy (同步数字序列)5、跳频扩频:FHSS frequency hopping spread spectrum6、同步转移模块:STM synchronous transfer module7、综合业务数字网:ISDNIntegrated Services Digital Network8、城域网:MAN Metropolitan Area Network9、传输控制协议/互联网协议:TCP/IPTransmission Control Protocol/Internet Protocol10、服务质量:QOS Quality of Service11、中继线:trunk line12、传输速率:transmission rate13、网络管理:network management14、帧结构:frame structure15、移动手机:Mobile Phone 手机 Handset16、蜂窝交换机:(Cellular switches)(电池开关cell switch)(cell 蜂房)17、天线:Antenna18、微处理器:microprocessor19、国际漫游:International roaming20、短消息:short message21、信噪比:SNR(Signal to Noise Ratio)22、数字通信:Digital communication23、系统容量:system capacity24、蜂窝网:cell network(cellular network)(Honeycomb nets)25、越区切换:Handover26、互联网:internet27、调制解调器:modem28、频谱:spectrum29、鼠标:Mouse30、电子邮件:electronic mail E-mail31、子网:subnet32、软件无线电:software defined radios33、网络资源:network resources 八、英译汉1、mobile communication:移动通信2、Computer user:计算机用户3、Frame format:帧格式4、WLAN:wireless local area network 无线局域网络5、Communication protocol:通信协议6、Transmission quality:传输质量7、Remote terminal:远程终端8、International standard:国际标准9、GSM:全球移动通信系统Global System for Mobile Communications10、CDMA:码分多址Code Division Multiple Access11、ITU:国际电信联盟International Telecommunication Union12、PCM:pulse code modulation 脉冲编码调制13、WDM:波分复用Wavelength Division Multiplex14、FCC:联邦通信委员会Federal communications commission15、PSTN:公用电话交换网Public Switched Telephone Network16、NNI:网络节点借口Network Node Interface17、WWW:万维网World Wide Web18、VOD:视频点播Video-On-Demand19、VLR:访问位置寄存器Visitor Location Register20、MSC:移动交换中心Mobile Switching Centre21、HLR:原籍位置寄存器Home Location Register22、VLSI:超大规模集成电路Very Large Scale Integrated Circuits23、Bluetooth technology:蓝牙技术24、Matched filter:匹配滤波器25、ADSL:非对称数字用户环路Asymmetrical Digital Subscriber Loop非对称数字用户线路(Asymmetric Digital Subscriber Line)26、GPS:全球定位系统Global Position System27、ATM:异步传输模式Asynchronous Transfer Mode1、脉冲编码调制(PCM)依赖于三个独立的操作:抽样、量化和编码。
介绍通信工程专业英语作文
介绍通信工程专业英语作文English Answer:Communication Engineering: A Gateway to Technological Advancements.Communication engineering is a captivating field that delves into the design, implementation, and maintenance of communication systems. It encompasses a comprehensive understanding of electrical engineering, computer science, and telecommunications principles. Engineers in this discipline leverage their expertise to develop cutting-edge technologies that enable seamless communication and data transfer.The curriculum of communication engineering programs typically includes core courses in circuit analysis, signal processing, digital communications, and network architectures. Students gain a profound understanding of the fundamentals of communication systems, from signalmodulation and detection to network protocols and data transmission techniques. They also delve into specialized areas such as wireless communications, optical fiber networks, and satellite communications.Graduates of communication engineering programs are equipped with the necessary skills and knowledge to work in a diverse range of industries. They can pursue careers as communication engineers, system designers, network administrators, or research and development engineers. Their expertise is crucial in developing innovative communication solutions for various applications, including telecommunications, mobile computing, biomedical devices, and the Internet of Things.The field of communication engineering is constantly evolving, driven by the relentless pursuit of technological advancements. Engineers in this discipline are constantly engaged in research and development, pushing the boundaries of what is possible. They play a vital role in shaping the future of communication technologies, ensuring seamless and efficient communication in an increasingly connected world.中文回答:通信工程,通向技术进步的大门。
通信工程专业英语翻译
通信一班杨林14112300954JXTA is a more than 20 years’hard-working work of Bill Joy, who is the chief scientist of Sun. JXTA technology is aplatform of network’s programming and computing, which is used to solve the modern distributed computing problems especially peer to peer problems. XTA’s research projectwill provide a new framework which canmake users more convenient to visit the PC, which is connected with the Internet, and thus further develop the space of Internet. At the same time, JXTA is also the continuation of Sun’s strategy ‘One Internet’. And JXTA will take a more positiveway to compete with the Microsoft’s Net strategy and Hailstorm’s plans.JXTA treaty defines a set of six protocols based on XML, which provides standardizedways fo r the nodes’ self-organizing into a node group, publishing and findingnotes resources, communicating and mutual monitoring. Firstly, The Endpoint Routing Protocol is used for founding node’s routing and sending message to the other node, and run across the potential of firewalls and network. Secondly, Rendezvous Protocol is used for spreading newsin the node group. Thirdly, Peer Resolver Protocolis used to send one or more notes to send common queries, and receives the response of query. Fourthly, Peer Discovery Protocol is used to release and find resources andinformation. Fifthly, Peer Information Protocolis used to obtain Information from other nodes.Finally, Peer Binding Protocol is used to allowa node to another node to set up virtual communication channels between multiple nodes or pipe.Compared to the general communication model, P2P has many advantages, but it also has a lot of problems to be solved. On the one hand, each Peer in P2P is active participants, but, in order to increase network performance, we need more peers’ participation.So, it will enlarge network, and it is a more complicated engineering to manage the network. On the other hand, the P2P protocol needs more interaction than the traditional ones, such as peer’s entering and quitt ing the network. And these factors will cause some negative influences to the function of the network.。
通信工程专业英语词汇大全
我们网络专业上有给你! 动态范围: Dynamic range 频率偏值: Frequency offset 符号率:Symbol rate 码域功率:code domain power 频分多址: Frequency Division Multiple Access 码分多址: Code Division Multiple Access 时分多址: Time Division Multiple Access 沃什码:Walsh code 误码率:Bit Error Rate,BER 帧误码率:Frame Error Rate,FER 循环冗余码:Cyclic Redundancy Code,CRC 时序分析:timing analyze 门限:threshold 非同步模式:Asynchronous Mode 同步模式:Synchronous Mode 邻道功率:ACP D―― Adjacent Channel Power 先进移动电话业务:AMPS---Advanced Mobile Phone Service组织协会: ANSI --- American National Standard Institute 美国国家标准局 BPT --- British Post and Telecommunication Standard 英国邮政与电信标准 CCIR --- International Radio Consultative Committee 国际无线电咨询委员会 CCITT --- International Telegraph and Telephone Consultative Committee国际/电报咨询委员会 CEPT --- Conference of European Post and Telecommunication Administrations欧洲邮电行政会议 EIA --- Electronic Engineers Association 电子工业协会美 ETSI --- European Telecommunication Standards Institute欧洲电信标准委员会 FCC --- Federal Communications Commission联邦通信委员会美 IEC --- International Electrotechnics Committee国际电工委员会 IEE --- Institution of Electrical Engineers电气工程师协会英 IEEE--- Institution of Electrical and Electronics Engineers, INC电气与电子工程师协会美 ITU --- International Telecommunication Union 国际电信联盟联合国 MPT --- Ministry of Post and telecommunications邮政与电信部英 TIA --- Telecommuni cations Industries Association电信工业协会美 WARC --- World Administrative Radio Conference世界无线电行政大会 ZVEI --- Zentralverband der Electechnischen Industrie电气工业中央协会德 ACP --- Adjacent Channel Power邻道功率 AMPS --- Advanced Mobile Phone Institute先进移动电话业务 APOC --- Advanced Paging Operator Code先进寻呼操作码 A VL --- Average Voice Level平均话音电平 BSC --- Base Site Controller基站控制器 CDMA --- Code Division Mulitiple Code码分多址 CDPD --- Cellular Digital Packet Data蜂窝分组数据系统 CSC --- Cell Site Controllor小区控制器 DCCH --- Digital Control Channel数字控制信道 DECT --- Digital Enhanced Cordless Telecommunications数字增强无绳电话 EDACS --- Enhanced Digital Access Communications System加强的数字接入通信系统 ERMES --- European Telecommunications Standards Institute欧洲无线电信息系统 ESN --- Electronics Serial Number电子串号 FDR --- Frequency Domain Reflectometry频域反射计 FLEX --- Flexible Paging System可变速寻呼系统 FOCC --- Forward Control Channel 前向控制信道 FVC --- Forward V oice Channel前向话音信道 GSC --- Golay Sequential Coding格雷码 GSM --- Global System for Mobile Communications全球移动通信系统 IBASIC --- Instrument BASIC仪器BASIC语言 IDC --- Instantaneous Deviation Control 瞬时频偏控制 IMSI --- International Mobile Station Identify国际移动台识别号码 LNA --- Low Noise Amplifier低噪声放大器 LPF/HPF --- Low/High Pass Filter低通/高通滤波器 LSB/USB --- Lower/Upper Side Band下/上边带 MCC --- Mobile Country Code移动业务国家号码 MCS --- Mobile Control Station移动控制站 MIN --- Mobile Identification Number移动识别码 MNC --- Mobile Network Code移动电话网号码 MSC ---Mobile Switching Center移动交换中心 MSIN --- Mobile Station Identification Number移动台识别码 MTSO --- Mobile Telephone Switching Office移动电话交换局 NMSI --- National Mobile Station Identify国内移动台识别号码 NMT --- Nordic Mobile Telephone北欧移动电话系统 OTP --- One Time Programmable一次性编程 PDC --- Personal Digital Cellular个人数字蜂窝系统 PHS --- Personal Handy-Phone System个人手持电话系统 PSTN ---Public Switching Telephone Network公用交换电话网 RECC --- Reverse Control Channel反向控制信道 RVC --- Reverse V oice Channel反向话音信道 RSSI --- Receiced Signal Strength Indicator接收信号场强指示 SCC --- Signalling Channel Controller信令信道控制器 SCM --- Station Class Mark移动台级别标志 SID --- Syste Indentification Number系统识别号 TACS --- Total Access Communications System全选址通信系统 TDMA --- Time Division Multiple Access时分多址 UUT --- Under Unit Test被测单元 VCC --- Voice Channel Controller话音信道控制器VSWR --- Voltages Standing Wave Ratio电压驻波比 1997年,爱立信公司向ETSI(欧洲电信标准委员会)提出了EDGE的可行性研究方案,并在同年得到认可。
通信工程中英文翻译
Combined Adaptive Filter with LMS-Based AlgorithmsBoˇ zo Krstaji´ c, LJubiˇ sa Stankovi´ c,and Zdravko Uskokovi´Abstract: A combined adaptive filter is proposed. It consists of parallel LMS-based adaptive FIR filters and an algorithm for choosing the better among them. As a criterion for comparison of the considered algorithms in the proposed filter, we take the ratio between bias and variance of the weighting coefficients. Simulations results confirm the advantages of the proposed adaptive filter. Keywords: Ad aptive filter, LMS algorithm, Combined algorithm,Bias and variance trade-off 1.IntroductionAdaptive filters have been applied in signal processing and control, as well as in many practical problems, [1, 2]. Performance of an adaptive filter depends mainly on the algorithm used for updating the filter weighting coefficients. The most commonly used adaptive systems are those based on the Least Mean Square (LMS) adaptive algorithm and its modifications (LMS-based algorithms).The LMS is simple for implementation and robust in a number of applications [1–3]. However, since it does not always converge in an acceptable manner, there have been many attempts to improve its performance by the appropriate modifications: sign algorithm (SA) [8], geometric mean LMS (GLMS) [5], variable step-size LMS(VS LMS) [6, 7].Each of the LMS-based algorithms has at least one parameter that should be defined prior to the adaptation procedure (step for LMS and SA; step and smoothing coefficients for GLMS; various parameters affecting the ste p for VS LMS). These parameters crucially influence the filter output during two adaptation phases:transient and steady state. Choice of these parameters is mostly based on some kind of trade-off between the quality of algorithm performance in the mentioned adaptation phases.We propose a possible approach for the LMS-based adaptive filter performance improvement. Namely, we make a combination of several LMS-based FIR filters with different parameters, and provide the criterion for choosing the most suitable algorithm for different adaptation phases. This method may be applied to all the LMS-based algorithms, although we here consider only several of them.The paper is organized as follows. An overview of the considered LMS-based algorithms is given in Section 2.Section 3 proposes the criterion for evaluation and combination of adaptive algorithms. Simulation results are presented in Section 4.2. LMS based algorithmsLet us define the input signal vector T k N k x k x k x X )]1()1()([+--=Λand vector ofweighting coefficients a s T N k k W k W k W W )]()()([110-=Λ.The weighting coefficients vectorshould be calculated according to:}{21k k k k X e E W W μ+=+ (1)where µ is the algorithm step, E{·} is the estimate of the expected value and k T k k k X W d e -=isthe error at the in-stant k,and dk is a reference signal. Depending on the estimation of expected value in (1), one defines various forms of adaptive algorithms: the LMS {}()k k k k X e X e E =,the GLMS {}()()∑=--≤<-=k i ik i k i k k a X e a aX e E 010,1, and the SA {}()()k k k k e sign X X e E =,[1,2,5,8] .The VS LMS has the same form as the LMS, but in the adaptation the step µ(k) is changed [6, 7].The considered adaptive filtering problem consists in trying to adjust a set of weightingcoefficients so that the system output,k T k k X W y =, tracks a reference signal, assumed as k k Tk k n X W d +=*,where k n is a zero mean Gaussian noise with the variance 2n σ,and *k W is the optimal weight vector (Wiener vector). Two cases will be considered:W W k =* is a constant (stationary case) and *k W is time-varying (nonstationary case). In nonstationary case the unknown system parameters( i.e. the optimal vector *k W )are time variant. It is often assumed thatvariation of *k W may be modeled as K k k Z W W +=+**1 is the zero-mean random perturbation,independent on k X and k n with the autocorrelation matrix []I Z Z E G Z T k k 2σ==.Note that analysis for the stationary case directly follows for 02=Z σ.The weighting coefficient vector converges to the Wiener one, if the condition from [1, 2] is satisfied.Define the weighting coefficientsmisalignment, [1–3],*k k k W W V -=. It is due to both the effects of gradient noise (weighting coefficients variations around the average value) and the weighting vector lag (difference between the average and the optimal value), [3]. It can be expressed as:()()()()*k k k k k W W E W E W V -+-=, (2)According to (2), the ith element of k V is:(3)where ()()k W bias i is theweighting coefficient bias and ()k i ρ is a zero-mean random variable with the variance 2σ.Thevariance depends on the type of LMS-based algorithm, as well as on the external noise variance()()()()()()()()()()()()k k W bias k W E k W k W k W E k V i i i i i i i ρ+=-+-=*2n σ.Thus, if the noise variance is constant or slowly-varying,2σ is time invariant for a particular LMS-based algorithm. In that sense, in the analysis that follows we will assume that 2σ depends only on the algorithm type, i.e. on its parameters.An important performance measure for an adaptive filter is its mean square deviation (MSD) of weighting coefficients. For the adaptive filters, it is given by, [3]:[]k T k k V V E MSD ∞→=lim . 3. Combined adaptive filterThe basic idea of the combined adaptive filter lies in parallel implementation of two or more adaptive LMS-based algorithms, with the choice of the best among them in each iteration [9]. Choice of the most appropriate algorithm, in each iteration, reduces to the choice of the best value for the weighting coefficients. The best weighting coefficient is the one th at is, at a given instant, the closest to the corresponding value of the Wiener vector.Let ()q k W i , be the i −th weighting coefficient for LMS-based algorithm with the chosen parameter q at an instant k. Note that one may now treat all the algorithms in a unified way (LMS: q ≡ µ,GLMS: q ≡ a,SA:q ≡ µ). LMS-based algorithm behavior is crucially dependent on q. In each iteration there is an optimal value qopt , producing the best performance of the adaptive al- gorithm. Analyze now a combined a daptive filter, with several LMS-based algorithms of the same type, but with different parameter q.The weighting coefficients are random variables distributed around the ()k W i *,with()()q k W bias i ,and the variance 2q σ, related by [4, 9]:()()()()q i i i q k W bias k W q k W κσ≤--,,*, (4)where (4) holds with the probability P(κ), dependent on κ. For example, for κ = 2 and a Gaussian distribution,P(κ) = 0.95 (two sigma rule).Define the confidence inte rvals for ()]9,4[,,q k W i :()()()[]q i q i i q k W k q k W k D κσσ2,,2,+-= (5)Then, from (4) and (5) we conclude that, as long as ()()q i q k W bias κσ<,,()()k D k W i i ∈*, independently on q. This means that, for small bias, the confidence inte rvals, for different s q ' of the same LMS-based algorithm, of the same LMS-based algorithm, intersect. When, on the other hand, the bias becomes large, then the central positions of the intervals for different s q ' are far apart, and they do not intersect.Since we do not have apriori information about the ()()q k W bias i ,,we will use a specific statistical approach to get the criterion for the choice of adaptive algorithm, i.e. for the values of q.The criterion follows from the trade-off condition that bias and variance are of the same order of magnitude, i.e.()()[]4,,q i q k W bias κσ≅.The proposed combined algorithm (CA) can now be summarized in the following steps: Step 1. Calculate ()q k W i ,for the algorithms with different s q 'from the predefined set {}K ,,2q q Q i =.Step 2. Estimate the variance 2qσ for each considered algorithm. Step 3. Check if ()k D i intersect for the considered algorithms. Start from an algorithm with largest value of variance, and go toward the ones with smaller values of variances. According to(4), (5) and the trade-off criterion, this check reduces to the check if()()()ql qm l i m i q k W q k W σσκ+<-2,, (6)is satisfied, where Q q q l m ∈,,and the following relation holds:Q q q h ql qh qm h ∉⇒>>∀,:222σσσ.If no ()k D i intersect (large bias) choose the algorithm with largest value of variance. If the ()k D i intersect, the bias is already small. So, check a new pair of weighting coefficients or, if that is the last pair, just choose the algorithm with the smallest variance. First two intervals that do not intersect mean that the proposed trade-off criterion is achieved, and choose the algorithm with large variance.Step 4. Go to the next instant of time.The smallest number of elements of the set Q is L =2. In that case, one of the s q 'should provide good tracking of rapid variations (the largest variance), while the other should provide small variance in the steady state. Observe that by adding few more s q ' between these two extremes, one may slightly improve the transient behavior of the algorithm.Note that the only unknown values in (6) are the variances. In our simulations we estimate 2qσ as in [4]: ()()()2675.0/1--=k W k W median i i q σ, (7)for k = 1, 2,... , L and 22qZ σσ<<. The alternative way is to estimate 2n σ as:∑=≈T i i n e T 1221σ,for x (i ) = 0. (8) Expressions relating 2n σ and 2q σ in steady state, for different types of LMS-based algorithms, are known from literature. For the standard LMS algorithm in steady state, 2n σ and2q σ are related 22nq q σσ=,[3]. Note that any other estimation of 2q σis valid for the proposed filter.Complexity of the CA depends on the constituent algorithms (Step 1), and on the decision algorithm (Step 3).Calculation of weighting coefficients for parallel algorithms does not increase the calculation time, since it is performed by a parallel hardware realization, thus increasing the hardware requirements. The variance estimations (Step 2), negligibly contribute to the increase of algorithm complexity, because they are performed at the very beginning of adaptation and they are using separate hardware realizations. Simple analysis shows that the CA increases the number of operations for, at most, N(L −1) additions and N (L −1) IF decisions, and needs some additional hardware with respect to the constituent algorithms.4.Illustration of combined adaptive filterConsider a system identification by the combination of two LMS algorithms with different steps. Here, the parameter q is μ,i.e. {}{}10/,,21μμ==q q Q .The unknown system has four time-invariant coefficients,and the FIR filters are with N = 4. We give the average mean square deviation (AMSD ) for both individual algorithms, as well as for their combination,Fig. 1(a). Results are obtained by averaging over 100 independent runs (the Monte Carlo method), with μ = 0.1. The reference dk is corrupted by a zero-mean uncorrelatedGaussian noise with 2n σ= 0.01 and SNR = 15 dB, and κ is 1.75. In the first 30 iterations thevariance was estimated according to (7), and the CA picked the weighting coefficients calculated by the LMS with μ.As presented in Fig. 1(a), the CA first uses the LMS with μ and then, in the steady state, the LMS with μ/10. Note the region, between the 200th and 400th iteration,where the algorithm can take the LMS with either stepsize,in different realizations. Here, performance of the CA would be improved by increasing the number of parallel LMS algorithms with steps between these two extrems.Observe also that, in steady state, the CA does not ideally pick up the LMS with smaller step. The reason is in the statistical nature of the approach.Combined adaptive filter achieves even better performance if the individual algorithms, instead of starting an iteration with the coefficient values taken from their previous iteration, take the ones chosen by the CA. Namely, if the CA chooses, in the k -th iteration, the weighting coefficient vector P W ,theneach individual algorithm calculates its weighting coefficients in the (k +1)-th iteration according to:{}k k p k X e E W W μ21+=+(9)Fig. 1. Average MSD for considered algorithms.Fig. 2. Average MSD for considered algorithms.Fig. 1(b) shows this improvement, applied on the previous example. In order to clearly compare the obtained results,for each simulation we calculated the AMSD . For the first LMS (μ) it was AMSD = 0.02865, for the second LMS (μ/10) it was AMSD = 0.20723, for the CA (CoLMS) it was AMSD = 0.02720 and for the CA with modification (9) it was AMSD = 0.02371.5. Simulation resultsThe proposed combined adaptive filter with various types of LMS-based algorithms is implemented for stationary and nonstationary cases in a system identification setup.Performanceof the combined filter is compared with the individual ones, that compose the particularcombination.In all simulations presented here, the reference dk is corrupted by a zero-mean uncorrelatedGaussian noise with 1.02=n σand SNR = 15 dB. Results are obtained by averaging over 100independent runs, with N = 4, as in the previous section.(a) Time varying optimal weighting vector: The proposed idea may be applied to the SA algorithms in a nonstationary case. In the simulation, the combined filter is composed out of three SA adaptive filters with different steps, i.e. Q = {μ, μ/2, μ/8}; μ = 0.2. The optimal vectors is generated according to the presented model with 001.02=Z σ,and with κ = 2. In the first 30 iterations the variance was estimated according to (7), and CA takes the coefficients of SA with μ (SA1).Figure 2(a) shows the AMSD characteristics for each algorithm. In steady state the CA does not ideally follow the SA3 with μ/8, because of the nonstationary problem nature and a relatively small difference between the coefficient variances of the SA2 and SA3. However,this does not affect the overall performance of the proposed algorithm. AMSD for each considered algorithm was: AMSD = 0.4129 (SA1,μ), AMSD = 0.4257 (SA2,μ/2), AMSD = 1.6011 (SA3, μ/8) and AMSD = 0.2696(Comb).(b) Comparison with VS LMS algorithm [6]: In this simulation we take the improved CA (9) from 3.1, and compare its performance with the VS LMS algorithm [6], in the case of abrupt changes of optimal vector. Since the considered VS LMS algorithm[6] updates its step size for each weighting coefficient individually, the comparison of these two algorithms is meaningful. All the parameters for the improved CA are the same as in 3.1. For the VS LMS algorithm[6], the relevant parameter values are the counter of sign change m 0 = 11,and the counter of sign continuity m 1 = 7. Figure 2(b)shows the AMSD for the compared algorithms, where one can observe the favorable properties of the CA, especially after the abrupt changes. Note that abrupt changes are generated by multiplying all the system coefficients by −1 at the 2000-th iteration (Fig. 2(b)). The AMSD for the VS LMS was AMSD = 0.0425, while its value for the CA (CoLMS) was AMSD = 0.0323.For a complete comparison of these algorithms we consider now their calculation complexity, expressed by the respective increase in number of operations with respect to the LMS algorithm. The CA increases the number of requres operations for N additions and N IF decisions.For the VSLMS algorithm, the respective increase is: 3N multiplications, N additions, and at least 2N IF decisions.These values show the advantage of the CA with respect to the calculation complexity.6. ConclusionCombination of the LMS based algorithms, which results in an adaptive system that takes the favorable properties of these algorithms in tracking parameter variations, is proposed.In the course of adaptation procedure it chooses better algorithms, all the way to the steady state when it takes the algorithm with the smallest variance of the weighting coefficient deviations from the optimal value.Acknowledgement. This work is supported by the Volkswagen Stiftung, Federal Republic of Germany.References[1] Widrow, B.; Stearns, S.: Adaptive Signal Processing. Prentice-Hall, Inc. Englewood Cliffs, N.J. 07632.[2] Alexander, S. T.: Adaptive Signal Processing –Theory and Applications. Springer-Verlag, New York 1986.[3] Widrow, B.; McCool, J. M.; Larimore, M. G.; Johnson, C. R.:Stationary and Nonstationary Learning Characteristics of the LMS Adaptive Filter. Proc. IEEE 64 (1976) 1151–1161.[4] Stankovic, L. J.; Katkovnik, V.: Algorithm for the instantaneous frequency estimation using time-frequency distributions with variable window width. IEEE SP. Letters 5 (1998), 224–227. [5] Krstajic, B.; Uskokovic, Z.; Stankovic, Lj.: GLMS Adaptive Algorithm in Linear Prediction. Proc. CCECE’97 I, pp. 114–117, Canada, 1997.[6] Harris, R. W.; Chabries, D. M.; Bishop, F. A.: A Variable Step (VS) Adaptive Filter Algorithm. IEEE Trans. ASSP 34 (1986),309–316.[7] Aboulnasr, T.; Mayyas, K.: A Robust Variable Step-Size LMSType Algorithm: Analysis and Simulations. IEEE Trans. SP 45 (1997), 631–639.[8] Mathews, V. J.; Cho, S. H.: Improved Convergence Analysis of Stochastic Gradient Adaptive Filters Using the Sign Algorithm. IEEE Trans. ASSP 35 (1987), 450–454.[9] Krstajic, B.; Stankovic, L. J.; Uskokovic, Z.; Djurovic, I.:Combined adaptive system for identification of unknown systems with varying parameters in a noisy enviroment. Proc. IEEE ICECS’99, Phafos, Cyprus, Sept. 1999.()()k W bias i 是加权系数的偏差,()k i ρ与方差2σ是零均值的随机变量差,它取决于LMS 的算法类型,以及外部噪声方差2n σ。
通信工程中英文对照外文翻译文献
中英文对照外文翻译(文档含英文原文和中文翻译)外文:Structure and function of the MCS-51 series Structure and function of the MCS-51 series one-chip computer MCS-51 is a name of a piece of one-chip computer series which Intel Company produces.This company introduced 8 top-grade one-chip computers of MCS-51 series in 1980 after introducing 8 one-chip computers of MCS-48 series in 1976.It belong to a lot of kinds this line of one-chip computer the chips have ,such as 8051, 8031,8751,80C51 BH, 80C31BH,etc., their basic composition, basic performance and instruction system are all the same.8051 daily representatives- 51 serial one-chip computer .An one-chip computer system is made up of several following parts:(1) One microprocessor of 8 (CPU).(2) At slice data memory RAM (128B/256B),it used to depositing not can reading /data that write, such as result not middle of operation,final result and data wanted to show, etc.(3)Procedure memory ROM/EPROM(4KB/8KB ), is used to preserve the procedure , some initial data and form in slice.But does not take ROM/EPROM within some one-chip computers, such as 8031 ,8032, 80C ,etc..(4)Four 8 run side by side I/O interface P0 four P3, each mouth canuse as introduction , may use as exporting too.(5)Two timer / counter, each timer /counter may set up and count in the way, used to count to the external incident, can setup into a timing way too, and can according to count or result of timing realize theontrol of the computer.(6)Five cut off cutting off the control system of thesource .(7)One all duplex serial I/O mouth of UART (universal asynchronous receiver/transmitter(UART)), is it realize one-chip computer or one-chip computer and serial communication of computer to use for.(8) Stretch oscillator and clock produce circuit, quartz crystal finely tune electric capacity need outer.Allow oscillation frequency as 12 now at most. Every the above-mentioned part was joined through the inside data bus .Among them, CPU is a core of the one-chip computer, it is the control of the computer and command centre, made up of such parts as arithmetic unit and controller,etc.. The arithmetic unit can carry on 8 persons of arithmetic operation and unit ALUof logic operation while including one, the 1 storing device temporarily of 8, storingdevice 2 temporarily, 8's accumulation device ACC, register B and procedure stateregister PSW, etc. Person who accumulate ACC count by 2 input ends entered ofchecking etc. temporarily as one operation often, come from person who store 1 operation is it is it make operation to go on to count temporarily , operation result and loop back ACC with another one. In addition, ACC is often regarded as the transferstation of data transmission on 8051 inside .The same as general microprocessor, it is the busiest register. Help remembering that agreeing with A expresses in the order.The controller includes the procedure counter ,the order is deposited, the order decipher, the oscillator and timing circuit, etc. The procedure counter is made up of counter of 8 for two, amounts to 16. It is a byte address counter of the procedure in fact, the content is the next IA that will carried out in PC. The content which changes it can change the direction that the procedure carries out .Shake the circuit in 8051 one-chip computers, only need outer quartz crystal and frequency to finely tune the electric capacity, its frequency range is its 12MHZ of 1.2MHZ. This pulse signal, as 8051 basic beats of working, namely the minimum unit of time. 8051 is the same as other computers, the work in harmony under the control of the basic beat, just like an orchestra according to the beat play that is commanded. There are ROM (procedure memory , can only read ) and RAM in 8051 slices (data memory, can is it can write ) two to read, they have each independent memory address space, dispose way to be the same with general memory of computer. Procedure 8051 memory and 8751 slice procedure memory capacity 4KB, address begin from 0000H, used for preserving the procedure and form constant. Data 8051- 8751 8031 of memory data memory 128B, address false 00FH, use for middle result to deposit operation, the data are stored temporarily and the data are buffered etc.. InRAM of this 128B, there is unit of 32 bytes that can be appointed as the job register, this and general microprocessor is different, 8051 slice RAM and job register rank one formation the same to arrange the location. It is not very the same that the memory of MCS-51 series one-chip computer and general computer disposes the way in addition. General computer for first address space, ROM and RAM can arrange in different space within the range of this address at will, namely the addresses of ROM and RAM, with distributing different address space in a formation. While visiting the memory, corresponding and only an address Memory unit, can ROM, it can be RAM too, and by visiting the order similarly. This kind of memory structure is called the structure of Princeton. 8051 memories are divided into procedure memory space and data memory space on the physics structure, there are four memory spaces in all: The procedure stores in one and data memory space outside data memory and one in procedure memory space and one outside one, the structure forms of this kind of procedure device and data memory separated form data memory, called Harvard structure. But use the angle from users, 8051 memory address space is divided into three kinds: (1) In the slice, arrange blocks of FFFFH , 0000H of location , in unison outside the slice (use 16 addresses). (2) The data memory address space outside one of 64KB, the address is arranged from 0000H 64KB FFFFH (with 16 addresses) too to the location. (3) Data memory address space of 256B (use 8 addresses). Three above-mentioned memory space addresses overlap, for distinguishing and designing the order symbol of different data transmission in the instruction system of 8051: CPU visit slice, ROM order spend MOVC, visit block RAM order uses MOVXoutside the slice, RAM order uses MOV to visit in slice. 8051 one-chip computer have four 8 walk abreast I/O port, call P0, P1, P2 and P3. Each port is 8 accurate two-way mouths, accounts for 32 pins altogether. Every one I/O line can be used as introduction and exported independently. Each port includes a latch (namely special function register), one exports the driver and a introduction buffer. Make data can latch when outputting, data can buffer when making introduction, but four function of pass way these self-same. Expand among the system of memory outside having slice, four port these may serve as accurate two-way mouth of I/O in common use. Expand among the system of memory outside having slice, P2 mouth see high 8 address off; P0 mouth is a two-way bus, send the introduction of 8 low addresses and data / export in timesharing The circuit of 8051 one-chip computers and four I/O ports is very ingenious in design. Familiar with I/O port logical circuit, not only help to use ports correctly and rationally, and will inspire to designing the peripheral logical circuit of one-chip computer to some extent. Load ability and interface of port have certain requirement, because output grade, P0 of mouth and P1 end output, P3 of mouth gradedifferent at structure, so, the load ability and interface of its door demand to have nothing in common with each other. P0 mouth is different from other mouths, its output grade draws the resistance supreme. When using it as the mouth in common use to use, output grade is it leak circuit to turn on, is it is it urge NMOS draw the resistance on taking to be outer with it while inputting to go out to fail. When being used as introduction, should write "1" to a latch first. Every one with P0 mouth candrive 8 Model LS TTL load to export. P1 mouth is an accurate two-way mouth too, used as I/O in common use. Different from P0 mouth output of circuit its, draw load resistance link with power on inside have. In fact, the resistance is that two effects are in charge of FET and together :One FET is in charge of load, its resistance is regular. Another one can is it lead to work with close at two state, make its President resistance value change approximate 0 or group value heavy two situation very. When it is 0 that the resistance is approximate , can draw the pin to the high level fast/view/9ca78b07caaedd3383c4d383.html?from=search 4/6 When resistance value is very large, P1 mouth, in order to hinder the introduction state high. Output as P1 mouth high electricity at ordinary times, can is it draw electric current load to offer outwards, draw the resistance on needn't answer and then.Here when the port is used as introduction, must write into 1 to the corresponding latch first too, make FET end. The structure of P2 some mouth is similar to P0 mouth, there are MUX switches. Is it similar to mouth partly to urge, but mouth large a conversion controls some than P1. P3 mouth one multi-functional port, mouth getting many than P1 it have "and " 3 door and 4 buffer". Two part these, make her besides accurate two-way function with P1 mouth just, can also use the second function of every pin, "and " door 3 function one switch in fact, it determines to be to output data of latch to output second signal of function. Act as W =At 1 o'clock, output Q end signal; Act as Q =At 1 o'clock, can output W line signal . At the time of programming, it is that the first function is still the second function but needn't have software that setup P3 mouth in advance . It hardware not inside is the automatic to have two function outputted when CPU carries on SFR and seeks the location (the location or the byte) to visit to P3 mouth /at not lasting lining, there are inside hardware latch Qs =1.The operation principle of P3 mouth is similar to P1 mouth.Output grade, P3 of mouth , P1 of P1 , connect with inside have load resistanceof drawing , every one of they can drive 4 Model LS TTL load to output. As while inputting the mouth, any TTL or NMOS circuit can drive P1 of 8051 one-chip computers as P3 mouth in a normal way . Because draw resistance on output grade of them have, can open a way collector too or drain-source resistance is it urge to open a way, do not need to have the resistance of drawing outer . Mouths are all accurate two-way mouths too. When the conduct is input, must write the corresponding port latch with 1 first. As to 80C51 one-chip computer, port can only offer milliampere of output electric currents, is it output mouth go when urging one ordinary basing of transistor to regard as, should contact a resistance among the port and transistor base, in order to the electricity while restraining the high level from exporting P1~P3 Being restored to the throne is the operation of initializing of an one-chip computer. Its main function is to turn PC into 0000H initially, make the one-chip computer begin to hold the conduct procedure from unit 0000H. Except that the ones that enter the system are initialized normally ,as because procedure operate it make mistakes or operate there aren't mistake, in order to extricate oneself from a predicament , need to be pressed and restored to the throne the key restarting too. It is an input end which is restored to the throne the signal in 8051 China RST pin. Restore to the throne signal high leveleffective , should sustain 24 shake cycle (namely 2 machine cycles ) the above its effective times. If 6 of frequency of utilization brilliant to shake, restore to the throne signal duration should exceed 4 delicate to finish restoring to the throne and operating.Produce the logic picture of circuit which is restored to the throne the signal。
通信工程专业英语翻译
Unit 6Part B1. Desktop systems allow remote users to share CAD files as well as other office documents created in spreadsheets, word processors, presentation packages, etc.桌面系统让远程用户能够共享计算机辅助设计档案以及其他一些制作在电子表格、文字处理器、图像程序包中的办公室文件。
3. At the World’s Fair 1964, AT&T demonstrated its first videophone, a desktop (or countertop)configuration that provided low quality images using analog technology.在1964年的世界博览会上,美国电话电报公司展示了其首款可视电话-一种桌面(或台式)机器。
因为使用的是模拟技术,它提供的图像质量不高。
5. Today, systems level implementers have to live within the constraints of standards-based compression algorithms, since standards are the foundation for interoperability, which in the communications field is absolutely necessary.如今,系统水平的操作者不得不受限于基于标准的压缩算法,因为标准时互用性的基础。
而在通行领域,互用性是极其重要的。
Part A1. The word “multimedia” is being used to describe a mixture of hardware, software and applications, with a consequent confusion in people’s mind as to what it is.“多媒体”一词被用来描述硬件、软件及应用的混合体。
(完整版)电子信息与通信工程专业英语期末必考翻译
1."In most cases, these signals originate as sensory data from the real world: seismic vibrations visual images, sound waves, etc. DSP isthe mathematics, the algorithms, and the techniques used to manipulate these signals after they have been converted into a digital form." 在大多数情况下,这些信号来源于人对真实世界的感觉,比如地震的震动,视觉图像,声音波形等。
数字信号处理是一种数学工具,是一种用来处理那些将上述信号转换成数字形式后的信号的算法和技术。
2.Fourier’s representation of functionsas a superposition of sines and cosines has become Ubiquitous for both the analytic and numerical solution of differential equations and for the analysis and treatment of communication signals 函数的傅里叶表示,即将函数表示成正弦和余弦信号的叠加,这种方法已经广泛用于微分方程的解析法和数值法求解过程以及通信信号的分析和处理。
3.If f (t ) is a nonperiodic signal, the summation of the periodic functions ,such as sine and cosine, does not accurately represent the signal. You could artificially extend the signal to make it periodic but it would require additional continuity at the end points . 如果f(t)是非周期信号,那么用周期函数例如正弦和余弦的和,并不能精确的表示该信号f(t)。
通信工程翻译
通信工程翻译通信工程翻译,内容尽量丰富,加一些用法和中英文对照例句Translation of Telecommunications Engineering, with rich contents and addition of usage and corresponding example sentences in both Chinese and English.1. 通信工程(tōng xìn gōng chéng) - Telecommunications Engineering- Example sentence: 我对通信工程有浓厚的兴趣。
(Wǒ duì tōng xìn gōng chéng yǒu nóng hòu de xìng qù) - I have a strong interest in telecommunications engineering.2. 信号传输(xìn hào chuán shū) - Signal Transmission- Example sentence: 无线电波是一种常用的信号传输方式。
(Wú xiàn diàn bō shì yī zhǒng cháng yòng de xìn hào chuán shū fāng shì) - Radio waves are a commonly used method of signal transmission.3. 无线通信(wú xiàn tōng xìn) - Wireless Communication- Example sentence: 无线通信技术在现代社会中起着重要的作用。
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通信一班序号:28 姓名:粟清明学号:14102301239
JXTA is a crystallization by Sun company's chief scientist Bill Joy's more than twenty years of brewing."JXTA technology is a platform for Network programming and calculation.To solve the modern distribution calculation especially peer-to-peer (Peer to Peer, P2P) in the calculation of the problem".
[1] JXTA research project,which will provide a new framework that make the user more convenient to access to connect on the Internet's personal computer resources, thus further expand Internet 's space. At the same time JXTA is also the Sun's "ONE Internet" strategic continuance, and will take a more positive attitude to compete with the .net strategy of Microsoft and Hailstorm plan .
JXTA agreement defines a set of six agreement based on XML, the organization of node into node group, release and found some resources, communication and mutual monitoring provides standardized method. (Endpoint Routing Protocol,ERP) is used for node found routing.To send a message to other nodes, and through the potential firewall and connection. (Rendezvous Protocol,RVP) s used for the nodes in the group to spread information.(Peer Resolver Protocol,PRP) is Used to one or more points to send general inquiries, and receive the response of inquiries. (Peer Discovery Protocol, PDP) is used to release and found advertising resources. (Peer Information Protocol, PIP) used to get other nodes state Information. (Peer Binding Protocol, PBP), can let a node with another node or between more nodes to set up virtual communication channel or pipeline.
Compared to the nowadays general communication mode .P2P has many advantages, but it also has a lot of problems waiting to be solved.Firstly, each Peer in P2P is an active participant,in order to make the network performance increase, they need more Peer's participation, so that will result in the network's huge, manage this network will is a complex project; Secondly, P2P agreement compares with traditional
client/server agreement it need more "interaction", such as Peer join or exit network,but these factors will cause some negative effect on network performance.
JXTA是Sun公司首席科学家Bill Joy二十多年酝酿的结晶。
“JXTA技术是网络编程和计算的平台,用以解决现代分布计算尤其是点对点(Peer to Peer,P2P)计算中出现的问题。
”[1]JXTA研究项目,将提供使用户更便捷地访问连接在互联网上的个人电脑资源的新框架,从而进一步拓展互联网的空间。
同时JXTA也是Sun的“ONE互联网”战略的延续,并且将以更积极的姿态与Microsoft的.Net战略和Hailstorm计划一争高低。
JXTA协议定义了一套基于XML的6个协议,对节点自组织成节点组、发布和发现点资源、通信和互相监控提供了标准化的方法。
端点路由协议(Endpoint Routing Protocol, ERP)用于节点发现路由,以向其它节点发送消息,并穿越潜在的防火墙和内网。
集合点(Rendezvous Protocol, RVP)协议用于在节点组中传播消息。
解析协议(Peer Resolver Protocol, PRP)用于向一个或多个点发送普通查询,并接收查询的响应。
发现协议(Peer Discovery Protocol, PDP)用于发布和发现资源广告。
信息协议(Peer Information Protocol, PIP)用于获取其它节点的状态信息。
节点绑定协议(Peer Binding Protocol, PBP),可以让一个节点与另一个节点或者多个节点间建立虚拟通信通道或管道。
相比于现在通用的通信模式,P2P有很多优势,但同时也有很多问题亟待解决。
首先,由于P2P中每个Peer都是积极的参与者,为了使网络性能增加,就需要比较多的Peer参与,这样就会造成网络的庞大,管理这样的网络必然会是一项复杂的工程;其次,P2P协议比传统的客户端/服务器协议需要更多的“交互”,比如Peer加入或退出网络,而这些因素将对网络的性能造成一定的消极影响。