far field help in matlab plz ?

[1d4n]

hey i need to write a matlab code to plot the graph of a far field

and i need help alil

the far field described like that

Eteta=[j*eta0*k0*l*sin(teta)*exp(-j*k0*r)]/(8*pi*r)x^

x^ is the direction

kr>>1


now they tell me
l=lambada/10

they want me to plot spatial map
of
abs(Eteta(phi,teta))

for
r=100*lambada

and phi between 0 to 360
abd teta between 0 to 180
with resolution of 1 angle

i tryed it but always i get matrix dimension error

and why they gave me x^ when we on r,teta,phi?

can some 1 give an exapmle to this code?

 

[Marat86]

Far field is a function of angular coordinates teta, phi. Therefore, Far field=E(teta, phi), normalized Far field=E(teta, phi)/Emax.

Far field of dipole f angular coordinate phi =1

%Far field of dipole f angular coordinate teta
t=-90:0.01:90;
E=cos(t*pi/180);
plot (t,E,'k');
grid on;

%Far field of antenna array

t=-90:0.01:90; % teta
f=45;% phi
n=8; % number of elements
l=280;% wavelength, mm
a=[1 1 1 1 1 1 1 1]; % amplitude distribution
d=220;% step of antenna array, mm
s=0;
for m=1:n
for k=1:n
s=s+a(k)*a(m)*exp(i*sin(t*pi/180)*(2*pi/l)*((k-1)*d*cos(f*pi/180)+(m-1)*d*sin(f*pi/180)));
end;
end;
plot (t,abs(s/max(s)),'k');
grid on;