电子专业英语Lesson5Low-passFil.ppt

2023/10/16,电子信息工程专业英语教程,1,Unit 2 Electronic Circuits,Lesson 5 Low-pass Filters电子信息工程专业英语教程任治刚 主编电子工业出版社,2023/10/16,电子信息工程专业英语教程,2,Lesson 5 Low-pass Filters,BackgroundsText tour Language in useVocabulary Structure Reading/writing techniques,2023/10/16,电子信息工程专业英语教程,3,Terminology DC:Direct Current 直流电AC:Alternating Current交流电Laplace transform 拉普拉斯变换Bode plot 伯德图transfer function 转移函数complex plane 复平面decaying-exponential response 衰减指数响应quality factor 品质因数,Backgrounds,2023/10/16,电子信息工程专业英语教程,4,Text tour,Outline First-Order Filters A simple RC integrator A simple RC low-pass filter Second-Order Low-Pass Filters An RLC low-pass filter the variables,2023/10/16,电子信息工程专业英语教程,5,First-Order Filters(1),A simple RC integratortransfer function,Figure 2.1a A simple RC integrator,2023/10/16,电子信息工程专业英语教程,6,First-Order Filters(1),Figure 2.1b A Bode plot of a simple integrator,Bode plot,2023/10/16,电子信息工程专业英语教程,7,First-Order Filters(2),Figure2.2a.A simple RC low-pass filter,A simple RC low-pass filtertransfer function,2023/10/16,电子信息工程专业英语教程,8,First-Order Filters(2),Figure 2.2b.The complex function of an RC low-pass filter,The complex function,2023/10/16,电子信息工程专业英语教程,9,First-Order Filters(2),Figure 2.2c.A Bode plot of a low-pass filter,Bode plot,2023/10/16,电子信息工程专业英语教程,10,Second-Order Low-Pass Filters,Figure2.3a An RLC low-pass filter,A simple RLC low-pass filtertransfer function,2023/10/16,电子信息工程专业英语教程,11,Second-Order Low-Pass Filters,Figure 2.3b A pole-zero diagram of an RLC low-pass filter,pole-zero diagram,2023/10/16,电子信息工程专业英语教程,12,Second-Order Low-Pass Filters,Figure2.4a.The complex function of a second-order low-pass filter(Q=0.707),2023/10/16,电子信息工程专业英语教程,13,Second-Order Low-Pass Filters,Figure 2.4b The complex function of a second-order low-pass filter(Q=2),2023/10/16,电子信息工程专业英语教程,14,Vocabulary variable,transient,order,response,formula,function,factor,origin StructureReading/writing techniques,Language in use,2023/10/16,电子信息工程专业英语教程,15,Vocabulary,2023/10/16,电子信息工程专业英语教程,16,Variable in dictionary,A quantity that can assume any of a given set of values.Any factor or condition which can be measured,altered,or controlled(e.g.,temperature,pressure,flow,liquid level,humidity,weight,chemical composition,color,etc.).A language object that may take different values,one at a time.Note:The values of a variable are usually restricted to a certain data type.In programming,a character or group of characters that refers to a value and,in the execution of a computer program,corresponds to an address.,2023/10/16,电子信息工程专业英语教程,17,Variable in text,You can easily derive the transfer function as where s is the complex-frequency variable+jand 0 is 1/RC.传输函数很容易推导出来（公式略）；其中，s是复频率变量+j，而0等于1/RC。,2023/10/16,电子信息工程专业英语教程,18,Variable in use,variable weather变化无常的天气a man of variable character反复无常的人variable standards变化的标准variable gears变速齿轮variable capital可变资本,2023/10/16,电子信息工程专业英语教程,19,Variable in use,complex variable复变数n-dimensional random variable n 维随机变量normal random variable正态随机变量real variable实变量scalar variable标量变量time variable时间变量,2023/10/16,电子信息工程专业英语教程,20,Transient in dictionary,Passing with time;transitory:短暂的Remaining in a place only a brief time:短期的，临时的Decaying with time,especially as a simple exponential function of time.瞬变的A transient phenomenon or property,especially a transient electric current.瞬变现象,2023/10/16,电子信息工程专业英语教程,21,Transient in text,When analyzing transient response using Laplace transforms,we use sL and 1/sC for the impedance of these elements.在使用拉普拉斯变换分析瞬态响应时，我们用sL和1/sC分别表示电感的阻抗和电容的阻抗。While the complex frequencys imaginary part(j)helps describe a response to AC signals,the real part()helps describe a circuits transient response.复频率的虚部有助于描述电路对交流信号的响应，复频率的实部有助于描述电路的瞬态响应。,2023/10/16,电子信息工程专业英语教程,22,Transient in use,damping transient阻尼瞬变过程forward switching transient正向开关瞬态high-speed transients快速瞬变现象initial transient起振过渡量,建起过程值,初始瞬值starting transient起动瞬变(过程)量,2023/10/16,电子信息工程专业英语教程,23,Transient in use,trailing transient后沿瞬变特性transition transient过渡瞬态turn-off transient关闭瞬态turn-on transient接通瞬态,2023/10/16,电子信息工程专业英语教程,24,Order in dictionary,A condition of logical or comprehensible arrangement among the separate elements of a group.顺序A condition of methodical or prescribed arrangement among component parts such that proper functioning or appearance is achieved:秩序Condition or state in general:情况The established system of social organization:体制Formal written instructions to report for military duty at a specified time and place.书面指示,2023/10/16,电子信息工程专业英语教程,25,Order in dictionary,The sum of the exponents to which the variables in a term are raised;degree.幂次An indicated number of successive differentiations to be performed.微分次数The number of elements in a finite group.元素个数The number of rows or columns in a determinant or matrix.行或列的数目,2023/10/16,电子信息工程专业英语教程,26,Order in text,A second-order filter provides the variables 0 and Q,which allow us to place poles wherever we want in the complex plane.二阶滤波器提供了0 和 Q这两个变量，我们可以将极点放置在复平面上任何需要的地方。As in the first-order case,the second-order low-pass transfer function tends to zero as frequency tends to infinity.当频率趋近于无穷时，二阶低通滤波器的传输函数趋近于零（和一阶低通滤波器的传输函数一样）。,2023/10/16,电子信息工程专业英语教程,27,Order in use,exponential order指数序模,指数级feeding order馈给次序order of equation方程的次数order of infinity无穷大阶order of magnitudes数量级order of matrix矩阵的阶,2023/10/16,电子信息工程专业英语教程,28,Order in use,additional order追加定货advance order预订单bulk order大宗订单,大批订货comparison order比较指令derivative order导数的级descending order递减次序,降序排列,2023/10/16,电子信息工程专业英语教程,29,Response in dictionary,The act of responding.答复A reply or an answer.回复或回答A reaction,as that of an organism or a mechanism,to a specific stimulus.反应,2023/10/16,电子信息工程专业英语教程,30,Response in text,However,as we can see from Figure 2.1b,the first-order filter does not provide a very selective frequency response.从图2.1b中，我们也可以看出：一阶滤波器的频率选择特性不是很好。Now lets examine the second-order functions frequency response and see how it varies with Q.现在，让我们考察一下二阶函数的频率响应及其随Q变化的情况。,2023/10/16,电子信息工程专业英语教程,31,amplitude-frequency response幅度频率响应,幅频响应曲线amplitude-phase response幅度相位响应complex frequency response复频响应flat response平坦响应(曲线)phase-shift response相移响应特性physiological response生理反应sinusoidal response正弦响应,正弦特性曲线,Response in use,2023/10/16,电子信息工程专业英语教程,32,steady-state response稳定态(反应)特性;稳定态灵敏度step response瞬态特性,过渡特性;阶跃响应underdamping response欠阻尼响应unit function response单位阶跃函数响应unit-impulse response单位脉冲响应zero input response零输入响应zero state response零状态响应,Response in use,2023/10/16,电子信息工程专业英语教程,33,Formula in dictionary,An established form of words or symbols for use in a ceremony or procedure.惯用语An utterance of conventional notions or beliefs;a hackneyed expression.客套话A method of doing or treating something that relies on an established,uncontroversial model or approach:准则，方案Drinking and driving is a formula for trouble.They proposed a third formula for the new swimming pool.,2023/10/16,电子信息工程专业英语教程,34,Formula in dictionary,A symbolic representation of the composition or of the composition and structure of a compound.分子式The chemical formula for water is H2OA prescription of ingredients in fixed proportion;a recipe.配方，处方the secret formula for a new rocket fuelA statement,especially an equation,of a fact,rule,principle,or other logical relation.公式formula of integration,2023/10/16,电子信息工程专业英语教程,35,Formula in text,If we think of s as frequency,this formula confirms the intuitive feeling that gain is inversely proportional to frequency.假如把s 当作频率的话，该公式印证了我们有关“增益和频率成反比”的直观推断。,2023/10/16,电子信息工程专业英语教程,36,Formula in use,analysis formula解析式approximate formula近似公式,近真公式backward interpolation formula后向插值公式Bessels interpolation formula贝塞尔内插公式bilinear formula双线性公式binomial formula二项式定理,二项式展开式,二项式公式Cauchy integral formula柯西积分公式,2023/10/16,电子信息工程专业英语教程,37,Formula in use,Gaussian distribution formula高斯分布公式half-angle formulas半角公式identical formula恒等公式iterative formula迭代公式Poisson integral formula泊松积分公式Poissons summation formula泊松求和公式,2023/10/16,电子信息工程专业英语教程,38,Function in dictionary,The action for which one is particularly fitted or employed.作用，功能Assigned duty or activity.职务，职责A specific occupation or role:角色，工作An official ceremony or a formal social occasion.重大聚会，庆典,2023/10/16,电子信息工程专业英语教程,39,函数：A mathematical entity whose value,that is,the value of the dependent variable,depends in a specified manner on the values of one or more independent variables,not more than one value of the dependent variable corresponding to each permissible combination of values from the respective range of the independent variables.功能：A specific purpose of an entity,or its characteristic action.操作：In data communication,a machine action such as carriage return or line feed.（如回车、换行）子程序：A subroutine that returns the value of a single variable,and that usually has a single exit,for example,subroutines that compute mathematical functions,such as sine,cosine,logarithm,or that compute the maximum of a set of numbers.,Function in dictionary,2023/10/16,电子信息工程专业英语教程,40,Function in text,As before,Figure 2.4a shows the function as a curved surface,depicted in the three-dimensional space formed by the complex plane and a vertical magnitude vector.图2.4a以曲面图的形式展示了（频率响应）函数，该曲面图是在由复频面和垂直幅度向量构成的三维空间中绘制的。,2023/10/16,电子信息工程专业英语教程,41,Function in use,function duty office roleThe central meaning shared by these nouns is the actions and activities assigned to,required of,or expected of a person.the function of a teacher 老师的作用a bank clerks duty 银行职员的职责assumed the office of financial adviser 担任财政顾问这个职务the role of a parent 父母的职责,2023/10/16,电子信息工程专业英语教程,42,normal probability function 概率正态分布函数orthonormal function 正交函数 self-correlation function 自相关函数trigonometrical function 三角函数unbounded function 无界函数unit step function 单位阶跃函数zero Bessel function 零次贝塞尔函数function of first degree 一次函数function of many variables 多元函数function of random variable 随机变量函数,Function in use,2023/10/16,电子信息工程专业英语教程,43,Factor in dictionary,One that actively contributes to an accomplishment,a result,or a process 因素One who acts for someone else;an agent.代理人A person or firm that accepts accounts receivable as security for short-term loans 代理商，经纪人One of two or more quantities that divides a given quantity without a remainder 因子2 and 3 are factors of 6;a and b are factors of ab.A quantity by which a stated quantity is multiplied or divided,so as to indicate an increase or decrease in a measurement 系数The rate increased by a factor of ten.,2023/10/16,电子信息工程专业英语教程,44,Factor in text,The second-order function decreases twice as fast,however,because of the s2 factor in the denominator.二阶低通滤波器的下降速度是一阶低通滤波器的两倍，这是其分母中出现 s2 因子的缘故。,2023/10/16,电子信息工程专业英语教程,45,Factor in use,Duty actor 负载比,占空系数;占空比Equation factor 换算率Fidelity factor 保真度,重现率,传真度Greatest common factor 最大公因数Prime factor 素因数,素因子Scale factor 标度因子,比例系数,定标因数,2023/10/16,电子信息工程专业英语教程,46,Factor in use,Transfer factor 传输系数,转移因子Transport factor(半导体)迁移率,Twiddle factor 旋转因子Utilization factor 设备利用率 Voltage regulation factor 电压调整系数Weighting factor 权重因数 Factor of the order 数量级,2023/10/16,电子信息工程专业英语教程,47,Origin in dictionary,The point at which something comes into existence or from which it derives or is derived.起源Ancestry:出身，血统：The fact of originating;rise or derivation:起源The point of intersection of coordinate axes,as in the Cartesian coordinate system.原点,2023/10/16,电子信息工程专业英语教程,48,Origin in text,Varying 0 changes the poles distance from the origin.改变0 会改变极点距离原点的位置。,2023/10/16,电子信息工程专业英语教程,49,Origin in use,antenna origin 天线原点band origin 谱带基线 coal origin 煤的来源grid origin 坐标原点infrared origin 红外辐射源noise origin 噪声源non-domestic origin 非国内原产 program origin 程序原点,2023/10/16,电子信息工程专业英语教程,50,Origin in use,seismical origin 震源time origin 时间原点origin of coordinates 坐标原点origin of infection 传染源origin of longitude and latitude 经纬度原点origin of mountains 山脉的发生origin of vector 矢量原点,2023/10/16,电子信息工程专业英语教程,51,origin source root Origin is the point at which something comes into existence:The origins of some words are unknown.Source can refer to the point of origin of a stream or a river;In another sense the term signifies the point at which something springs into being or from which it derives or is obtained:The Alpine sources of the Rhine(John Foster Kirk).The great original source of revenue.the wages of labor(Adam Smith).,Origin in use,2023/10/16,电子信息工程专业英语教程,52,origin source root Root often denotes what is considered the fundamental cause of or basic reason for something:The mysterious.is the source of all true art and science(Albert Einstein).Lack of money is the root of all evil.(George Bernard Shaw).,Origin in use,2023/10/16,电子信息工程专业英语教程,53,Structure,2023/10/16,电子信息工程专业英语教程,54,Reading/Writing techniques,