201213020306刘天宇信号.doc

信号与线性系统分析 ---matlab实验报告 班级：电子三班 姓名：刘天宇 学号：201213020306 指导老师：杨斯涵 单位阶跃信号 f=sym(heaviside(t+3)-2*heaviside(t)) ezplot(f,[-5,4]), hold on,plot([0,0],[-1,1]), axis([-5,4,-1.1,1.1]),hold off f =heaviside(t+3)-2*heaviside(t) 其中含有heaviside.m文件： Function Y=heaviside(X) Y=zeros(size(X)); Y(X0)=1; Y(X==0)=NaN; 2单位冲击信号 chongji(-1,5,0) t=0:0.05:3; f=exp(-1.5*t); plot(t,f) axis([0,3,0,1.2]) title(单边指数信号) text(3.1,0.05,t) 3指数信号 t=0:0.05:3; f=exp(-1.5*t); plot(t,f) axis([0,3,0,1.2]) title(单边指数信号) text(3.1,0.05,t) 4 抽样函数 t=-3*pi:pi/100:3*pi; ft=sinc(t/pi); plot(t,ft) title(抽样函数Sa(t)) xlabel(t) ylabel(Sa(t)) 5 矩形脉冲信号 t=0:0.001:4; T=2; ft=rectpuls(t-2,T); plot(t,ft) axis([0,4,-0.5,1.5]) title(矩形脉冲信号) xlabel(t) ylabel(rectpuls(t)) 6 三角波信号 t=-3:0.001:3; ft=tripuls(t,4,0.5); plot(t,ft) title(三角波信号) xlabel(t) ylabel(tripuls) 7离散时间序列 单位阶跃序列 正弦序列 k=0:40; subplot(2,1,1) stem(k,cos(k*pi/8),filled) title(cos(k*pi/8)) subplot(2,1,2) stem(k,cos(2*k),filled) title(cos(2*k) 8 信号的时域运算与时域变换 （1） syms t f=sym((t/2+1)*(heaviside(t+2)-heaviside(t-2))) subplot(2,3,1),ezplot(f,[-3,3]) y1=subs(f,t,t+2) subplot(2,3,2),ezplot(y1,[-5,1]) syms t f=sym((t/2+1)*(heaviside(t+2)-heaviside(t-2))) subplot(2,3,1),ezplot(f,[-3,3]) y1=subs(f,t,t+2) subplot(2,3,2),ezplot(y1,[-5,1]) y2=subs(f,t,t-2) subplot(2,3,3),ezplot(y2,[-1,5]) y3=subs(f,t,-t) subplot(2,3,4),ezplot(y3,[-3,3]) y4=subs(f,t,2*t) subplot(2,3,5),ezplot(y4,[-2,2]) y5=-f subplot(2,3,6),ezplot(y5,[-3,3]) f =(t/2+1)*(heaviside(t+2)-heaviside(t-2)) y1 =(1/2*t+2)*(heaviside(t+4)-heaviside(t)) y2 =1/2*t*(heaviside(t)-heaviside(t-4)) y3 =(-1/2*t+1)*(heaviside(-t+2)-heaviside(-t-2)) y4 =(t+1)*(heaviside(t+1)-heaviside(t-1)) y5 =-(1/2*t+1)*(heaviside(t+2)-heaviside(t-2)) （2 syms t f1=sym((t-4)*(heaviside(t)-heaviside(t-4))) subplot(2,3,1),ezplot(f1) f2=sym(sin(2*pi*t)) subplot(2,3,4),ezplot(f2,[-4,4]) y1=subs(f1,t,-t) f3=f1+y1 subplot(2,3,2),ezplot(f3) f4=-f3 subplot(2,3,3),ezplot(f4) f5=f2*f3 subplot(2,3,5),ez