zlp2lp.m

用MATLAB实现数字信号处理的程序

%Lp2lp函数：模拟低通滤波器到模拟低通滤波器的转换
[z,p,k]=buttap(4);
[b,a]=zp2tf(z,p,k);
[bt,at]=lp2lp(b,a,150*2*pi);
[hl,wl]=freqs(b,a);
[hh,wh]=freqs(bt,at);
subplot(2,1,1),semilogx(wl,abs(hl));grid;
subplot(2,1,2),semilogx(wh,abs(hh));