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Radiation power of an antenna

  1. May 25, 2016 #1
    I am reading Jackson's book on classical electrodynamics.
    It said in page 412 to 415 (3rd edition) that the total power radiated by a
    dipole is proportional to k^4 (equation 9.24)
    quadrupole is proportional to k^6 (equation 9.49)
    But why does the linear antenna at page 412, which is a dipole, radiate at k^2 (equation 9.29)?
  2. jcsd
  3. May 25, 2016 #2
    The dipole moment, p, has ω in the denominator (equation 9.27). Thus the c2|p|2 terms in 9.24 replace two of the k's.
    Last edited: May 26, 2016
  4. May 26, 2016 #3
    so the (real) power for a dipole should be proportional to k^2 instead of k^4 ?
  5. May 26, 2016 #4
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