How do I detremine the directions of maximum radiation and generate a plot of the normalised radiation intensity?

For a dipole antenna of length L=lambda/4, Use Matlb to detremine the directions of maximum radiation and generate a plot of the nirmalised radiation intensity??? Can any one answer this for me please..

I don't know how to start with. Can any one please help me. Thanking you.

Answer 1

[Youssef Khmou]

 hi Rama,

The radiation pattern can be computed in two regions, Near Field and Far field,

Here is version i made for lambda/4 far field, try to verify it :

 theta=0:0.01:4*pi; %in radian
 Z0=377;           % wave impedance of the vaccum  in Ohm
 R=3;            %  a distance from origin in meter
 lambda=0.05;        %just a number to make calculus on it , in meter
 I=1.25;           %current in Amper
 L=lambda/4;       %in meter
 k=2*pi/lambda;
 E=((j*Z0*k*I*L)/(4*pi*R))*exp(-j*k*R)*sin(theta);
 figure, polar(theta,abs(E))

[Rama Krishna]

Thank you so much..