山东大学2011-2012学年2学期数字信号处理（双语）课程试卷(A) 得分侧普人 3.(15 pts)Given two finite sequences: gm={-3,2,4n=0,1,2,Mm={2,4,0,5n=0,1,2,3, 架 (a)Compute yu[n]=gin*h[n]:(5 pts) (b)Compute ydn]=gin④hln：(5pts) (c)Can yL[n]be computed by using DFT?IfyL[n]can be computed,then write down the steps.(5 pts) 家 得分圆卷人 5.(15 pts)The system function of a stable LTI system is H(e)= 2/5 25 1-2:-）(1+0.5） (a)Plot the poles and zeros of the system function in the z-plane.(5 pts (b)Determine the ROC and the impulse response h[n].(10 pts) 器 得分卷人 4.(15 pts)Consider a causal continuous-time system with impulse response he(t)and system function ( 3+2 Assume the sampling time is 7=0.Is,use impulse invariance to determine H(z)for a discrete-time system such that hin]=he(nT). 第2项共4页2011-2012 2 数字信号处理（双语） （A） 2 4 3．(15 pts) Given two finite sequences: g[n] = { -3, 2, 4; n = 0, 1, 2 }, h[n] = { 2, -4, 0, 1; n = 0, 1, 2, 3 }, (a) Compute yL[n] = g[n]*h[n] ； （5 pts） (b) Compute yC[n] = g[n] ④h[n] ；（5 pts） (c) Can yL[n] be computed by using DFT? If yL[n] can be computed, then write down the steps.（5 pts） 4．(15 pts) Consider a causal continuous-time system with impulse response hc(t) and system function 2 3 2 ( ) 2 3 1 a s H s s s + = + + . Assume the sampling time is T = 0.1 s, use impulse invariance to determine H(z) for a discrete-time system such that h[n] = hc(nT). 5．(15 pts) The system function of a stable LTI system is ( ) ( ) ( ) 1 1 2 5 2 5 1 2 1+0.5 H z z z − − = − − . (a) Plot the poles and zeros of the system function in the z-plane. （5 pts） (b) Determine the ROC and the impulse response h[n]. （10 pts） 得分 阅卷人 得分 阅卷人 得分 阅卷人