Visualizing Radiation Patterns of Linear Antennas in MATLAB

[golfingboy07]

Questions:


1. A short dipole pz is oscillating with angular frequency omega. Draw contours of equal intensity of the radiation from this dipole in the x,z plane

2. A linear centre fed antenna is oriented along the z axis. Draw contours of equal intensity of the radiation from this dipole, in the x,z plane, for a half wave antenna and for a full wave antenna. Compare these cases , and also compare with the case of the short dipole

Thanks

 

[J77]

Any ideas?

 

[chroot]

We're not going to do your homework for you. Do you have any idea how to approach this problem? If you can tell us where you're stuck, we can help.

- Warren

 

[golfingboy07]

Sorry. I realize that.
Not sure where to start- maybe with <S> = (p^2 * omega^4* sin^2theta)/ (32*pi*epsilion_zero*c^3*r^2) for the short dipole case
And then use the 'contour' command in MATLAB. Have a range of theta values for a particular r and then change r to get multiple contours. Not really sure on this though. Any ideas to get me started?

Thanks

GM

 

[golfingboy07]

Or better yet maybe use the 'polar' plotting function in MATLAB...

 

[J77]

In Matlab you need to set up a grid.

In cartesian form, easiest if square:

x=[-10:0.1:10] y=[-10:0.1:10]

Then you evaluate your function z at all these points.

ie. size(z)=[length(x),length(y)]

You can then use contour(x,y,z) to plot it.