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A question about the phase of pump wave of a dipole and radiation of the dipole

  1. May 23, 2010 #1
    When I am dealing with dipole radiation, I faces a difficult problem. Is the phase of the radiation the same as pump wave?
  2. jcsd
  3. May 23, 2010 #2


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    I look at it this way. The current and voltage on a dipole are in about quadrature, but not exactly. At resonance, when the reactive impedances cancel, there is a resistance of about 72Ω (an in-phase component) which we call the radiation resistance and this represents the 'load' which free space presents to the transmitter, 'transformed' by the action of the dipole. In free space, the actual ratio of fields, which are in phase, is equivalent to a resistance of about 377Ω.
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