LPF example (with MatLAb code): Chebyshev N=5, 7, 9, Wc=3.8GHz

%Chebyshev LPF if N odd

close all;home;clc;clear all;

%input

N=9;

Am=0.1; %ripple level in dB

R0=50;

Wc=2*pi*3.8e9;

%================================================

beta=log(coth(Am/17.37));

gamma=sinh(beta/(2*N));

for k=1:1:N

a(k,1)=sin((2*k-1)*pi/(2*N));

b(k,1)=gamma^2+(sin(k*pi/N))^2;

end

g(1,1)=2*a(1,1)/gamma;

for k=2:1:N;

g(k,1)=(4*a(k-1,1)*a(k,1))/(b(k-1,1)*g(k-1,1));

end

g(N+1,1)=1;

for k=1:1:N;

kt=mod(k,2)

if kt==1;

CL(k,1)=1e12*g(k,1)/(R0*Wc);%C unit pF

else

CL(k,1)=1e9*R0*g(k,1)/Wc;%L unit nH

end

end

CL