《信号与系统A》 一、主要目标和主要内容： 主要教学目标 Signals and Systems is an elementary important course for students who majored in electronics and information engineering or in communication and information engineering,and this course may lay a tight basis for their further study in digital signal processing, communication systems, and control systems. This course covers the fundamental tools used in continuous-time and discrete-time signal and system analysis. Matlab computer assignments are included to help students acquire an in-depth understanding of the key concepts. Topics included in this course are time-invariant system analysis, Fourier transform, Laplace transform, and introduction to sampling theory. After students have study through the whole semester,they will be expected to master the following skills: 1) Determine whether a signal has the following properties:discrete time, continuous time, power, energy, periodic, aperiodic, even, odd 2) Perform the following operations on signals, alone or in combination:amplitude scaling, addition, multiplication, differentiation, integration time scaling, reflection, time shifting 3) Identify and use the following elementary signals: exponentials, sinusoids, complex exponentials, exponentially damped sinusoids step functions, impulses, sifting and time scaling properties of impulses. 4) Determine whether an input/output description for a system has the following properties:stability,memory,memoryless,causality, invertibility (simple cases),time invariance, linearity 5) Evaluate the convolution sum and integral given an input and the impulse response. 6) Use the commutative, associative, and distributive properties of convolution. 7) Determine whether a system described by an impulse response has properties:memoryless,causal,stable. 8) Find the step and frequency responses of a system given the impulse response 9) Characterize the natural response, forced response, and complete response for systems described by second order difference or differential equations 10) Determine whether a system described by a difference or differential equation is stable 11) Evaluate the DTFS,FS,DTFT,and FT representations of time signals using the defining equations 12) Evaluate the time domain signal corresponding to DTFS,FS, DTFT,and FT representations using the defining equations 13) Use the frequency response to solve for the input, output, or impulse response of a system given the other two signals 14) Determine the frequency response of systems described by differential and difference equations 15) Use the FT or DTFT representation for periodic signals to analyze mixtures of periodic and aperiodic signals 16) Determine the conditions on the sampling rate or interval that guarantee a bandlimited signal can be uniquely reconstructed from its samples 17) Identify the specifications of an anti-imaging filter for reconstructing continuous-time signals from samples 18) Find the Laplace transform of a time signal using the efining equation 19) Find the Laplace transform and inverse Laplace transform using the tables of transforms and properties 20) Use the method of partial fractions to find inverse Laplace transforms 21) Use the unilateral Laplace transform to solve second order differential equations. Identify the natural and forced response components of the solution. 教学的主要内容 （一） Contents and Schedule 1. Introduction (Chap.1 ) Remarks:More attention focus on section1.4,1.5,1.6,1.7,1,8 2. Time-domain representations of linear time-invariant systems (Chap.2) Remarks:Lay a strong emphasis on section 2.2,2.3,2.4,2.5; Know clearly the different representations of LTI which located in section 2.7,2.8,2.9, also, can solving differential and difference equation proficiently and correctly by reading section 2.10,2.11 3. Fourier representations of signals and linear time-invariant systems (Chap.3) Remarks:Explain the principles of FT firstly and then spend more time to study different representations of the different signals, which located in section 3.3,3.4,3.5, 3.6 and 3.7; Emphases lies in section 3.10-3.17, by studying these sections you should mast many properties related to FT 4. Applications of Fourier representations to mixed signal classes (Chap.4) Remarks:More attention should be paid on section 4.5 and 4.6.Let students understand the principle of sampling and know how to reconstruct a continuous time signal for its samples. 5. Laplace-transform (Chap.6) Remarks:Focus more attention on explaining the definition and properties of LT which located in section6.2-6.5; and remember to study section 6.13 which may be very important for system analysis in frequency domain. 6. z-transform (Chap.7) Remarks:Pay more attention on section7.6,7.7 and 7.8.Explain the definition of transfer function and how to determining the frequency response from Poles and Zeros. （二） 序 号 实验名称 内容提要或要求 实验 学时 每组 人数 实验 类型 主要仪器设备 01 Exp.1 Study the sampling theory carefully and after that,you should design yourself a signal and find out how to correctly sample it,and then recover the signal from its samples.Programming Tools can be Matlab,C or VC++,etc. 2 3 Programming PC 02 Exp.2 Study Laplace transform carefully and find out the relationship between the stability of a LTI system and the location of its poles. 2 3 Programming PC 03 Exp.3 Read the context of chap.4 carefully and write a program to realize the 2-based FFT through which you should know the exact reason why the DFT of discrete signal fastly can be calculated efficiently. 2 3 Programming PC 二、授课教师和授课对象： 授课教师:张华君 授课对象:通信工程/电子信息工程专业本科生 三、课程类型和学时学分： 课程类型:专业基础课 课程学时:72学时 课程学分:4学分 四、教学方式（授课形式和考核方式）： 授课形式:课堂讲授为主 考核方式:考试(闭卷) 五、教材与参考书目： 教材和主要参考资料 教材 A.V.Oppenheim,A.S.Willsky,and S.H.Nawab,Signals and Systems,2nd Ed.,Prentice-Hall,1997.Ed.,Wiley,2003. 参考资料 Recommended Readings: (1)S.Haykin and B.Van Veen,Signals and Systems,2nd 2004. (2) G.E.Carlson,Signal and Linear System Analysis,2nd Ed.,John Wiley&Sons,1998.