实验1常用信号产生实验目的：学习用MATLAB编程产生各种常见信号。实验内容：矩阵操作：输入矩阵：x=[1324;5312;3658;7674]x=1324531236587674引用x的第二、三行；x([23],:)ans=53123658引用x的第三、四列；x(:,[34])ans=24125874求矩阵的转置；x'ans=1537336621574284求矩阵的逆；y=inv(x)y=-1.25000.25000.6250-0.12503.4167-0.0833-1.87500.3750-0.7500-0.25000.37500.1250-1.62500.12501.0625-0.3125单位脉冲序列：产生δ（n）函数；n=-8:8;x=[zeros(1,8),1,zeros(1,8)];stem(n,x)产生δ（n-5）函数；n=-8:8;x=[zeros(1,13),1,zeros(1,3)];stem(n,x)δ（n）δ（n-5）产生阶跃序列：产生U（n）序列；n=-10:10;x=[zeros(1,10),ones(1,11)];stem(n,x)产生U（n-n0）序列；取No=3n=-10:10;x=[zeros(1,13),ones(1,8)];stem(n,x)U（n）U（n-3）产生指数序列：x(n)=0.5n=-8:0.5:8;x=0.5*(3/4).^n;stem(n,x)产生正弦序列：x=2sin(2π*50/12+π/6)n=-8:0.5:8;x=2*sin((2*pi/12)*n+pi/6);stem(n,x)产生取样函数：t=-8:0.001:8;x=sinc(t/pi);plot(t,x)产生白噪声：产生[0，1]上均匀分布的随机信号：t=0:0.01:1;plot(t,tand(1,length(t)))产生均值为0，方差为1的高斯随机信号：t=0:0.01:1;plot(t,randn(1,length(t)))生成一个幅度按指数衰减的正弦信号：x(t)=Asin(w*t+phi).*exp(-a*t)A=8;f0=4;phi=0;w=2*pi*f0;a=8;t=0:0.01:1;x=A*sin(w*t+phi).*exp(-a*t);plot(t,x)产生三角波：t=-3:0.01:3;plot(t,tripuls(t,3,0));holdon;plot(t,tripuls(t-5/2,1,-1));holdoff;axis([-2,4,0,2])