Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

MATLAB Radiation Questions

  1. Sep 12, 2006 #1

    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

  2. jcsd
  3. Sep 13, 2006 #2


    User Avatar

    Any ideas?
  4. Sep 13, 2006 #3


    User Avatar
    Staff Emeritus
    Science Advisor
    Gold Member

    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
  5. Sep 13, 2006 #4
    Sorry. I realise 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?


  6. Sep 13, 2006 #5
    Or better yet maybe use the 'polar' plotting function in MATLAB...
  7. Sep 14, 2006 #6


    User Avatar

    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.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook