Here is a code for rectangular patch to obtain the Z para of a single port. To change it into circular follow erip's direction. Be careful during finding the root's of derivative of bessel function. The values given in that book are wrong.
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function y=green(a,b,d,er,del,x1,y1,width,fr,L)
c=3*10^8; %velocity of light in m per sec.
eo=8.854*10^(-12); % farad per meter
mu=4*pi*10^(-7); % perm. of substrate.
sum11=0;
w=2*pi*fr;
ksqr=(w^2)*(mu*eo*er*(1-j*del));
for m=0:L
kx=m*pi/a;
if(m==0)
sigma_m=1;
else
sigma_m=2;
end
for n=0:L
ky=n*pi/b;
if(n==0)
sigma_n=1;
else
sigma_n=2;
end
phi_mn_1=(cos(kx*x1))*(cos(ky*y1))*sinc(ky*width/2);
den=((kx^2)+(ky^2)-(ksqr));
su11=sigma_m*sigma_n*phi_mn_1*phi_mn_1;
sum11=sum11+su11/den;
end
end
y=(j*w*mu*d*sum11/(a*b));
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eirp said:
Hi!
I recommend you to look into
Garg,Bhartia,Bahl,Ittipiboon:MS antenna design handbook.
(uploaded by Basskiler too)
On pp. 144-148 are Greens functions you required.
Next you need equations on pp. 93+
It's quite easy to code, I think it's enough for you..
Time ago I've coded similar program - I have problems with determinig radiation Q, results strongly depends on it...
Regards,
Eirp