afd_chb1.m

the file contain many matlab signal source code and many example .

function [b,a]=afd_chb1(Wp,Ws,Rp,As);
% Analog Lowpass Filter Design:Chebyshev-1
% -------------------------------------
% [b,a]=afd_chb1(Wp,Ws,Rp,As);
% b=Numberator coefficients of Ha(s)
% a=Denominator coefficients of Ha(s)
% Wp=Passband edge frequency in rad/sec;Wp>0
% Ws=Stopband edge frequency in rad/sec;Ws>Wp>0
% Rp=Passband ripple in +dB;(Rp>0)
% As=Stopband attenuation in +dB;(As>0)
%
if Wp<=0
    error('Passband edge must be larger than 0')
end
if Ws<=Wp
    error ('Stopband edge must be larger than Passband edge')
end
if (Rp<=0)|(As<0)
    error('PB ripple and/or SB attenuation must be larger than 0')
end
ep=sqrt(10^(Rp/10)-1);
A=10^(As/20);
OmegaC=Wp;
OmegaR=Ws/Wp;
g=sqrt(A*A-1)/ep;
N=ceil(log10(g+sqrt(g*g-1))/log10(OmegaR+sqrt(OmegaR*OmegaR-1)));
fprintf('\n * * * Chebyshev -1 Filter Order=% 2. of \n',N)
[b,a]=u_chb1ap(N,Rp,OmegaC);