DSP课程大作业英文版_图文(精).docVIP

Lab Report of DSP 姚志浩 5090309481 F0903018 Lab 1 Discrete-Time Fourier Transform (1 Generate and plot the discrete-time signal Solution: It’s a simple sequence ,we can get the discrete-time signal using Matlab. Chat 1-1 simple sequence sample (2 Determine and plot the DTFT of the signal Solution: DTFT is the Z-Transform on the Unit Circle, we can easily find the Z-Transform ： With ‘freqz’ function，we can get the amplitude-frequency and phase frequency response curve. Chart 1-2 DTFT Of the sequence (3 A linear and time-invariant system is described by the difference equation where abcd is equal to the last four digits of your student ID number. (i Is the system BIBO-stable? (ii Determine and sketch the impulse response , of the system. Determine the stability of the system by observing . (iii Determine and plot the output of the system, if the input is . Solution: (1 My student ID number is 5090309481，corresponding a b c d will be9 4 8 1,and the difference equation will be ； Characteristic equation will be ，we can get three pole points : ， All the pole points are in the unit circle, so the system is stable. (2 Create a function “impseq” to get a impulse signal. Here we use the function “filter”, we can get the impulse response: Chart 1-3 Unit Step Response We get ans = 22.1234, so the system is stable. (3 if the input is ,the input sequence and output sequence are showed : Addendum ：Matlab Program List 1-1. n=[0:30] x=(0.93.^n.*cos(0.14*pi*n+pi/3; stem(n,x;title(x(n;xlabel(n;ylabel(x(n 1-2 . n=[0:30];x=(0.89.^n.*(stepseq(0,30,0 w=[0:500]*2*pi/500; X=exp(j*w./(exp(j*w-0.89*ones(1,501; mag=abs(X;ang=angle(X figure(1;plot(w/pi,mag;grid ylabel(|X(w|;xlabel(w(in pi unit;title(DTFT of x(n-magnitude figure(2;plot(w/pi,ang;grid ylabel(argX(w/pi;xlabel(w (in pi unit;title(DTFT of x(n-angle 1-3. (2 num=[9,-4,8,-1];den=[1,-0.65,0.35,0] x=impseq(0,0,100;n=[0:100] h=filter(num,den,x stem(n,h;xlabel(n;ylabel(y(n;title(Impluse Response ;sum(abs(h (3num=[9,-4,8,-1];den=[1,-0.65,