• §2.1 系统的数学模型 • §2.2 LTI系统的响应 • §2.3 LTI系统的冲激响应与阶跃响应 • §2.4 卷积

1.双边Z变换及其收敛域ROC 2.ROC的特征,各类信号的ROC,零极点图 3.Z反变换,利用部分分式展开进行反变换。 4.由零极点图分析系统的特性。 5.常用信号的Z变换,Z变换的性质

一、本课程要研究的问题是什么? 二、本课程的任务和地位。 三、为什么要学习该课程? 四、怎样才能学好该课程?

一、本课程要研究的问题是什么? 二、本课程的任务和地位。 三、为什么要学习该课程? 四、怎样才能学好该课程?

Thursday, November 13, 2003 Directions: The exam consists of 6 problems on pages 2 to 19 and work space on pages 20 and 21. Please make sure you have all the pages. Tables of Fourier series properties as well as CT Fourier transform and dt Fourier transform properties and tables are supplied to you at the end of this booklet. Enter all your work and your answers directly in the spaces provided on the printed pages of this book- let. Please make sure your name is on all sheets. You may use bluebooks for scratch work, but we will not grade them at all. all sketches must be adequately

Reading Assignments Lectures #18-20 PS#9: Chapters 9 1l(through Subsection 11.3.4 )of O&W Lectures #21-22 PS#10: Chapters 10& 11(through Subsection 11. 3.4)of O&w Exercise for home study(not to be turned in, although we will provide solutions)

Problem set SolutioN Exercise for home study o&W8.35 (a) From the system diagram, we see that a(t)=a(t)cos(wet) Using the multiplication property ZGu)= o(X(u)* FT(cos wct)) FT of cos wt is two impulses with area T at +wc. Therefore, Z(w)is the spectrum

The lowpass filter H(u) has a cutoff frequency wc=205T rad/ sec. Thus, c(t)is r(t) where all terms with frequency above we are removed by the lowpass filter. The terms which are kept have kwol 205T rad /sec k|< 10.25, so the output, ac(t),is r(t)= To obtain n, we sample c(t) every T=5 10-3 seconds with an impulse train The sampling frequency is 400T=2 x maximum frequency in c(t). Therefore

REMINDER: Quiz 1 will be held from 7: 30 to 9: 30 p. m. Tuesday, October 14 The quiz will cover material in Chapters 1-3 of o&w Lectures and Recitations through september 26, Problem Sets 1-3 and that part of Problem Set 4 involving problems from Chapter 3 Reading assignments

Reading Assignments Lectures #5-6& PS#2: Chapter 3 of Oppenheim and Willsky(O& w) Lectures #3-4 &z PS#3: Chapters 3&4 of Oppenheim and Willsky(O&w) Exercise for home study (not to be turned in, although we will provide solutions)