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1、通信与电子信息科技英语Scientific English on Communications andElectronic Information 张敏瑞 张红 编著August 2007北京邮电大学出版社,2023/10/19,1,目 录,Unit 1 Random Processes 补充学习资料1Unit 2 Channel Capacity Unit 3 Pulse Code Modulation Fundamentals Unit 4 Fundamentals of Channel Coding Unit 5 Modulation Unit 6 Speech Coding Unit
2、7 Digital Image Processing 补充学习资料2Unit 8 Introduction to MATLAB,2023/10/19,2,Unit 9 Implementation of DSP Systems Unit 10 Characteristics of Data Transmission Circuits Unit 11 Microwave Radio Transmission Unit 12 Fiber Optic Unit 13 Mobile Wireless Unit 14 ATM Unit 15 Internet Unit 16 Network Manage
3、ment Unit 17 Security of Mobile and Wireless Networks Unit 18 Abstract 补充学习资料3,2023/10/19,3,Unit 1 Random Processes,NEW WORDSPHRASES NOTESEXERCISES,Back,2023/10/19,4,NEW WORDS,Unit 1,2023/10/19,5,Unit 1,2023/10/19,6,Unit 1,2023/10/19,7,Back,Unit 1,2023/10/19,8,PHRASES,random process 随机过程on the avera
4、ge 平均,按平均数计算;一般地说make measurement 量度sample function 样本函数statistical average 统计平均(值)probability density function 概率密度函数statistical characteristic 统计特性autocorrelation function 自相关函数,Unit 1,2023/10/19,9,in connection with 关于，与有关 physical significance 物理意义Fourier transform 傅里叶变换power spectral density 功率
5、谱密度be at liberty to(do)被允许;可随意gaussian process 高斯过程physical fact 外界存在的事实upper-frequency limit 频率上限fall off 下降,减少,Unit 1,2023/10/19,10,Back,in the limit 在极限情况下 delta function 函数，狄垃克函数 random pulse 随机（杂乱）脉冲 time invariant 时不变的 Parsevals theorem 巴塞瓦尔定理 statistically independent 统计独立 successive pulse 连续
6、脉冲 be representative of 表示，代表，代表的特征,Unit 1,2023/10/19,11,NOTES,1 Thus,we would expect that a single die would yield a particular outcome,on the average,of 1 time out of 6.Similarly,with many dice we would expect that 1/6 of the dice tossed would yield a particular outcome.因此我们会预期平均掷6次骰子会有一次得到特定的结果。类
7、似地，当掷很多骰子时有1/6的骰子会得到特定的结果。out of(from among)从中。如：five out of six votes 六人中有五人投票on the average 平均,按平均数计算;一般地说,Unit 1,2023/10/19,12,2 Throughout this text we shall assume that the random processes with which we shall have occasion to deal are ergodic.在整个课文中我们假定要研究的随机过程都是各态历经过程。occasion n.场合,时机,机会 have
8、 occasion 有的理由；有必要 have no occasion 没有的理由；没有必要deal v.论及，论述 a book that deals with the Middle Ages.一本讨论中世纪时候的书random process：随机过程。这是通信与电子信息类专业的一门重要理论基础课，其它有关课程的英文名称请参阅本课课后补充学习资料1。,Unit 1,2023/10/19,13,3 Hence,if we should select some sample function,a knowledge of the value of at time would be of no
9、assistance in improving our ability to predict the value attained by that same sample function at time.所以如果我们选定某样本函数，则它在时刻的值并不能帮助我们预测相同样本函数在 时刻的值。some adj.某一，任一.例如:He went to some place in Africa.他到非洲某地去knowledge of n.对的认识,Unit 1,2023/10/19,14,4 Such noise is referred to as white noise in analogy wi
10、th the consideration that white light is a combination of all colors,that is,colors of all frequencies.这种噪声称为“白”噪声，类似于白光是所有颜色光即所有频率有色光的混合。analogy n.类似,类推.例如：in a rough analogy 大致，类似地,Unit 1,2023/10/19,15,5 The pulses are of the same form but have random amplitudes and statistically independent rando
11、m times of occurrence.,这些脉冲形状相同，但具有随机幅度并且出现次数随机、统计独立。,Back,Unit 1,2023/10/19,16,EXERCISES,.Please translate the following words and phrases into Chinese.,1.sample function 样本函数2.ensemble average 总体均值3.physical significance 物理意义 4.a Fourier transform pair 傅立叶变换对5.deterministic waveform 确定性波型,6.in the
12、 limit 在极限情况下7.time invariant 时不变的8.an upper-frequency limit 频率上限9.Parsevals theorem 巴塞瓦尔定理10.random pulses 随机脉冲,Unit 1,2023/10/19,17,.Please translate the following words and phrases into English.,1.随机过程 random process2.统计平均 statistical average3.随机变量 random variable4.自相关函数 autocorrelation function5
13、.傅里叶变换 Fourier transform6.功率谱密度 power spectral density7.概率密度函数 probability density function,8.高斯过程 gaussian process9.平稳过程 a stationary process10.统计独立 statistically independent11.时间平均(值)time average12.统计特性 statistical characteristic13.各态历经过程 ergodic process14.函数(狄垃克函数)delta function,Unit 1,2023/10/19
14、,18,.Fill in the blanks with the missing word(s).,1.The ensemble averages will be identical _ the statistical averages and may be represented by the same symbols.with2.The averages determined by measurements a single sample function _ successive times will yield a time average,which we represent as.
15、on,at,Unit 1,2023/10/19,19,3.Suppose,for example,that the statistical characteristics of the sample functions _ the ensemble were changing with time.in4.For it may happen that while each sample function is stationary the individual sample functions may differ statistically _ one another.from5.As an
16、extension of that result we shall define the power spectral density of a random process _ the same way.in,Unit 1,2023/10/19,20,6.It is _ interest to inquire whether defined _ Eq.(2)for a random process has a physical significance which corresponds to the physical significance of for deterministic wa
17、veforms.of,in 7.Correspondingly,we state,without proof,that when is defined _ a random process,as in Eq.(2),_ the transform of,then has the significance that.for,as,Unit 1,2023/10/19,21,8.Hence,if we should select some sample function,a knowledge of the value of at time t would be no assistance _ im
18、proving our ability to predict the value attained by that same sample function at time.of,in9.Whenever we make an observation or measurement of the pulse waveform which extends over a duration long enough so that the average observed pulse shape,such as their amplitudes,widths,and spacings are repre
19、sentative of the waveform generally,we shall find that Eq.(1.12)applies.over,Unit 1,2023/10/19,22,10.Let us select a section of this waveform which extends _-T/2_ T/2.from,to11.Since we have assumed an ergodic process,we are at liberty to _(perform,performing)the averaging _ any sample function of t
20、he ensemble,since every sample function will yield the same result.perform,over,Unit 1,2023/10/19,23,.Answer the following questions according to the text.,1.Please describe the relationship between the ergodic process and the stationary process.An ergodic process is stationary,but a stationary proc
21、ess is not necessarily ergodic.2.What are random pulses?The random pulses are of the same form but have random amplitudes and statistically independent random times of occurrence.,Unit 1,2023/10/19,24,3.What is the relationship between the power spectral density and the autocorrelation function?The
22、power spectral density and the autocorrelation function constitute a Fourier transform pair.4.What is referred to as ergodic?When the nature of a random process is such that ensemble and time averages are identical,the process is referred to as ergodic.,Unit 1,2023/10/19,25,5.What is white noise?Why
23、 do we call it white?White noise has a power spectral density which is uniform over all frequencies.Such noise is referred to as white noise in analogy with the consideration that white light is a combination of all colors,that is,colors of all frequencies.,Back,Unit 1,2023/10/19,26,Reading Random V
24、ariables,New Words and PhrasesQuestions,Unit 1,Back,2023/10/19,27,New Words and Phrases,signify vt.表示,意味misnomer n.误称;使用不当的名称identification n.识别,辨别discrete adj.离散的distinct adj.独特的;性质或种类不同的bullet n.子弹wind current n.风流,气流mark n.测标,标志,Unit 1,Back,2023/10/19,28,1.What is a random variable?The random var
25、iable is used to signify a rule by which a real number is assigned to each possible outcome of an experiment.2.What is a discrete random variable?If in any finite interval X()assumes only a finite number of distinct values,then the random variable is discrete.,Questions,Unit 1,2023/10/19,29,3.What i
26、s a continuous random variable?If,however,X()can assume any value within an interval,the random variable is continuous.4.Suppose denotes the possible outcomes of an experiment,please give an example that is not a number.For example,the experiment might consist of running a horse race where the outco
27、me of interest is the name of the winner.The symbols might then be the names of the horses.,Back,Unit 1,30,补充学习资料1,相关专业部分大学课程英文名称,Back,2023/10/19,31,Philosophy 哲学Political Economics 政治经济学Principle of Marxism 马克思主义原理History of Chinese Revolution 中国革命史History of the Chinese Communist Party 中共党史College
28、 English 大学英语Specialized English 专业英语College Physics 大学物理General Physics 普通物理Experiment of College Physics 物理实验,补充一,2023/10/19,32,Advanced Mathematics 高等数学 Linear Algebra 线性代数 Discrete Mathematics 离散数学 Matrix Theory 矩阵(理)论 Probability Theory 概率论 Engineering Mathematics 工程数学 Function of Complex Varia
29、ble 复变函数 Computational Method 计算方法 Equation of Mathematical Physics 数理方程 Integral Transformation 积分变换,补充一,2023/10/19,33,Vector Analysis 矢量分析 Field Theory 场论 Random Process（or：Stochastic Process）随机过程 Basic Application of Computer 计算机应用基础 Programming with C Language C语言编程 Principle of Microcomputer 微机
30、原理 Electronic Circuit 电子线路 Analogue Electronic Technology Basis 模拟电子技术基础 High Frequency Electronic Technology 高频电子技术 Low Frequency Electronic Technology 低频电子技术,补充一,2023/10/19,34,Radio Technology Basis 无线电基础Signal&Linear System 信号与线性系统Principle of Communication 通信原理Digital Communication 数字通信Principle
31、 of Communication System 通信系统原理Spread Spectrum Communication System 扩频通信系统Digital Mobile Communication 数字移动通信Digital Satellite Communication 数字卫星通信Microwave Communication 微波通信Mobile Communication 移动通信,补充一,2023/10/19,35,Satellite Communication 卫星通信 Fiber Optical Communication 光纤通信 Multimedia Communic
32、ation 多媒体通信 Communication Countermeasure 通信对抗 Modern Communication System 现代通信系统 Modern Communication Network 现代通信网 Integrated Service Digital Network 综合业务数字网 SPC Exchange Fundamental 程控交换原理 ATM Principle and Application ATM原理及应用 Digital TV 数字电视,补充一,2023/10/19,36,Cable Television 有线电视 Electromagneti
33、c Field Theory 电磁场理论 Electromagnetic Field&Magnetic Wave 电磁场与电磁波 Microwave Technique 微波技术 Antenna Principle 天线原理 Random Signal Analysis 随机信号分析 Digital Signal Processing 数字信号处理 Digital Image Processing 数字图像处理 Adaptive Signal Processing 自适应信号处理 Speech Signal Processing 语言信号处理,补充一,2023/10/19,37,Voice a
34、nd Speech Processing 语音处理 Pattern Recognition 模式识别 Information Theory 信息论 Information and Coding Theory 信息论与编码理论 Optical Information Processing 光信息处理 Information Technology 信息技术 Information Fusion 信息融合 Information Management 信息管理 Electronic Commerce 电子商务 Multimedia Technique 多媒体技术,补充一,2023/10/19,38,
35、Design and Analysis of Information System 信息系统分析与设计 Computer Graphics 计算机图形学 Basis of Software Technique 软件技术基础 Software Engineering 软件工程 Database Principle 数据库原理 Visual C+Programming VC+程序设计 Object-oriented Technique 面向对象技术 Computer Network Basis 计算机网络基础 Network Management 网络管理 Management Informati
36、on System 管理信息系统,补充一,2023/10/19,39,81.Computer Network Cryptography Technology 计算机网络安全与保密技术82.Computer Simulation Technology and Application 计算机仿真技术及应用Operating System 操作系统Data Structure 数据结构 Experiment of Microcomputer System 微机系统实验Computer Interface Technology 计算机接口技术Single Chip Processor 单片机PLC P
37、rinciple and Application 可编程控制器原理及应用ASIC Design 专用集成电路设计Assembly Language 汇编语言,补充一,2023/10/19,40,91.VHDL and Digital System Design Using EDA VHDL语言与数字系统EDA设计 Artificial Intelligence 人工智能 Computer Control Technique 计算机控制技术 Modern Control Theory 现代控制理论 Automatic Control Theory 自动控制理论 Literature Retrie
38、val 文献检索 Electrical Engineering Practice 电工实习 Physical Education 体育 Military Theory 军事理论 Music 音乐 Graduation Project(Thesis)毕业设计（论文）,补充一,Back,2023/10/19,41,Unit 2 Channel Capacity,NEW WORDSPHRASES NOTESEXERCISES,Back,2023/10/19,42,NEW WORDS,Unit 2,2023/10/19,43,Unit 2,2023/10/19,44,Unit 2,2023/10/19
39、,45,Back,Unit 2,2023/10/19,46,PHRASES,1.enter into 参加，成为一部分，涉及2.due to 由于;起因于;归功于3.be something of 有一点4.in principle 原则上,大致上 on principle 按照原则（或道德标准）5.provided that 假如,设若6.probability of error 误码率，误差概率(or：error probability)7.be close to 接近,靠近,Unit 2,2023/10/19,47,8.bandlimited gaussian channel 限带高斯信
40、道9.physical system 物理系统,实际系统10.turn out 结果，结果是（常与to,that连用）11.lower bound 下界,下限12.upper limit 上限13.root-mean-square 均方根，均方根值；均方根(的)root-mean-square error 均方根(有效值)误差14.amount of information 信息量（or：information content;quantity of information;information quantity）15.ideal lowpass filter 理想低通滤波器,Unit 2,
41、2023/10/19,48,16.rise time 上升时间17.as a matter of convenience 为方便起见18.white Gaussian noise 高斯白噪声(or:white gaussian noise)19.on the other hand 另一方面20.trade off 交替换位，折衷选择(tradeoff n.折衷,权衡)21.signal-to-noise ratio 信号噪声比，信噪比（SNR，S/N）22.be free to 随意,任意,不受拘束23.make up for 补偿,Back,Unit 2,2023/10/19,49,NOTE
42、S,1 Shannons theorem says that it is possible,in principle,to devise a means whereby a communications system will transmit information with an arbitrarily small probability of error provided that the information rate R is less than or equal to a rate C called the channel capacity.香农定理表示原则上有可能设计一种方法，
43、使得如果信息速率R小于或等于一个称为信道容量的速率C，通信系统就能以任意小的误码率传送信息。whereby(关系副词)凭那个；由此。例:a system whereby a new discovery may arise 由此可能产生新发现的体系 a plan whereby to escape 逃走的办法provided conj.（常与that连用）假若；倘若；倘使。例如:You may keep the book a further week provided(that)no one else requires it.倘若这本书没有其他人想借的话，你可以再续借一个礼拜。（亦作：provi
44、ding）,Unit 2,2023/10/19,50,2 This negative theorem states that if the information rate R exceeds a specified value C,the error probability will increase toward unity as M increases,and that also,generally,in this case where R C,increasing the complexity of the coding results in an increase in the pr
45、obability of error.这个逆定理表明如果信息速率R超过规定值C，那么误码率将随着M的增加不断向1增加，通常，在R C的情况下，编码复杂度的增加还会导致误码率的增加。该句中主语是This negative theorem，谓语state的2个并列宾语为2个由that引导的从句，其一为：(that)if the information rate R exceeds a specified value C,the error probability will increase toward unity as M increases,其二为：(that)also increasing
46、the complexity of the coding results in an increase in the probability of error（此从句中谓语是results in）。句中的generally,in this case where R C,都是修饰语，这种插入式修饰语通常由逗号隔开，很容易识别。,Unit 2,2023/10/19,51,3 The levels have been separated by an interval,where is a number presumed large enough to allow recognition of ind
47、ividual levels with an acceptable probability of error.电平按 间隔划分，其中 是事先规定的一个很大的数，足够允许在可接受的误码率情况下正确区分各个电平。,Unit 2,2023/10/19,52,4 Assuming an even number of levels,the levels are located at voltages,etc.假定有偶数级，则每级位于电压为 等处。etc（拉丁语）et cetera，adv.等等，以及其它等等。,Unit 2,2023/10/19,53,5 Thus for a fixed signal
48、power and in the presence of white gaussian noise the channel capacity approaches an upper limit with increasing bandwidth.因此对于信号功率一定并存在白高斯噪声时，信道容量将随着带宽的增加而趋近于其上限值。approach:vt.趋近；approach to：vt.接近，趋近于这种表示法在数学极限中经常用到，例如：approach infinity 趋近（接近）无穷大 approach infinity as a limit 趋近于无穷大为极限 approach unity
49、 趋近于1,Back,Unit 2,2023/10/19,54,6 If the SNR is increased to S/N=15 and B decreased to 3 kHz,the channel capacity remains the same.With a 3kHz bandwidth the noise power will be 3/4 as large as with 4 kHz.Thus the signal power will have to be increased by the factor.如果SNR增加到15，B减小到3 kHz,则信道容量保持不变。带宽为
50、3kHz时噪声功率将是4 kHz带宽时的3/4，所以信号功率必须增加到 倍。increase to vt.增加到，增至；increase by vi.增加。例如：1)increase(M)by N（使M）增加N2)Increase M to N 把M增加到N 关于增减倍数的表达方法应该搞清楚，否则会影响科技文阅读的理解。a factor of M M倍，例如：increase by a factor of 5 增加4倍，增加到5倍,Back,Unit 2,2023/10/19,55,EXERCISES,.Please translate the following words and phra
