matlab1.docx

长江大学电工电子实验中心实验报告信号与系统实验报告（1）连续信号的运算实验目的1掌握用Matlab绘制波形图的方法，学会常见波形的绘制2掌握用Matlab编写函数的方法3周期信号与非周期信号的观察。加深对周期信号的理解实验内容1、用MATLAB画出下列信号的波形。 (a) ; (b) ; (c) ; (d) ; (e) ; (f) 解：（1）程序t=linspace(-10,10,400);f1=heaviside(cos(t);figure(1),plot(t,f1,linewidth,2);axis(-10 10 -0.2 1.2)xlabel(Time(sec),ylabel(f1(t),title(a)t=linspace(-4,4,400);f2=abs(t)/2.*(heaviside(t+2)-heaviside(t-2);figure(2),plot(t,f2,linewidth,2);axis(-4 4 -0.2 1.2)xlabel(Time(sec),ylabel(f2(t),title(b)t=linspace(-1,3,400);f3=sin(pi*t).*(heaviside(-t)-heaviside(2-t);figure(3),plot(t,f3,linewidth,2);axis(-1 3 -1.2 1.2)xlabel(Time(sec),ylabel(f3(t),title(c) t=linspace(-2,2,400);f4=sign(t).*rectpuls(t,2);figure(4),plot(t,f4,linewidth,2);axis(-2 2 -1.2 1.2)xlabel(Time(sec),ylabel(f4(t),title(d) t=linspace(-1,4,400);f5=rectpuls(t,6).*tripuls(t-2,4);figure(5),plot(t,f5,linewidth,2);axis(-1 4 -0.2 1.2)xlabel(Time(sec),ylabel(f1(t),title(e) t=linspace(-3,3,400);f6=heaviside(2-abs(t).*sin(pi*t);figure(6),plot(t,f6,linewidth,2);axis(-3 3 -1.2 1.2)xlabel(Time(sec),ylabel(f1(t),title(f)（2）波形2、用基本信号画出图2.1-10中的信号。图2.1-10解：（1）程序t=linspace(-1,7,400); f1=2*rectpuls(t-3,6)+2*rectpuls(t-3,2);figure(1),line(t,f1,linewidth,2);axis(-1,7 -0.2 4.2)xlabel(t),ylabel(f1(t)set(gca,XTick,0,2,4,6,YTick,0,2,4)%定义坐标轴刻度标记的位置set(gca,XTickLabel,0,2,4,6,YTickLabel,0,2,4)%定义坐标轴刻度的标签 f2=2*rectpuls(t-3,6)+2*tripuls(t-3,2);figure(2),line(t,f2,linewidth,2);axis(-1 7 -0.2 4.2)xlabel(t),ylabel(f2(t)set(gca,XTick,0,2,3,4,6,YTick,0,2,4)set(gca,XTickLabel,0,2,3,4,6,YTickLabel,0,2,4) f3=6*tripuls(t-3,6)-2*tripuls(t-3,2);figure(3),plot(t,f3,linewidth,2);axis(-1 7 -0.2 4.2)xlabel(t),ylabel(f3(t)set(gca,XTick,0,2,4,6,YTick,0,4)set(gca,XTickLabel,0,2,4,6,YTickLabel,0,4)（2）波形3 用MATALB画出图2.1-11所示信号。其中，K=10，A=5。图2.1-11 解:（1）程序t=linspace(-1,4*pi,400);f1=10*abs(sin(t).*heaviside(t);figure(1),line(t,f1,linewidth,2);axis(0,2*pi,0,11.2)set(gca,XTick,0,pi,2*pi,YTick,0,10)set(gca,XTickLabel,0,pi,2*pi,YTickLabel,0,A)xlabel(t),ylabel(f1(t) t=linspace(-0.5,3,400);f2=5*t.2.*rectpuls(t-0.5,1)+5*(t-1).2.*rectpuls(t-1.5,1)+5*(t-2).2.*rectpuls(t-2.5,1);figure(2),line(t,f2,linewidth,2);axis(-0.5 3.5 -0.2 5.2)set(gca,XTick,0,1,2,3,YTick,0,5)set(gca,XTickLabel,0,1,2,3,YTickLabel,0,A)xlabel(t),ylabel(f2(t)text(string,t2,position,1.3,1.7)（2）波形4 试用Matlab绘制出如下连续时间信号的时域波形，并观察信号是否为周期信号。若是周期信号，周期是多少？(a) (b) (c) 解：（1）程序t=linspace(-8,8,400);f1=3*sin(pi/2*t)+2*sin(pi*t)+sin(2*pi*t);figure(1),plot(t,f1,linewidth,2);axis(-8 8 -5 5)xlabel(Time(sec),ylabel(f1(t) t=linspace(-8,8,400);f2=sin(t)+2*cos(4*t)+sin(5*t);figure(2),plot(t,f2,linewidth,2);axis(-8 8 -2.5 4.5)xlabel(Time(sec),ylabel(f2(t