afd_butt.m

数字信号处理的MATLAB仿真加实验指导

function[b,a]=afd_butt(Omegap, Omegar,Ap,Ar);

if Omegap<=0
   error('通带边缘必须大于0')
end
if Omegar<=Omegap
   error('阻带边缘必须大雨通带边缘')
end
N=ceil((log10((10^(0.1*Ar)-1)/(10^(0.1*Ap)-1)))/(2*log10(Omegar/Omegap)));
fprintf('\n***BW Filter Order=%2.0f\n',N);
OmegaC=Omegap/((10^(Ap/10)-1)^(1/(2*N)));
[b,a]=u_buttap(N,OmegaC);