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Saturday, July 9, 2016

Loop Wire Antenna

From the post "Energy Accounting With Fourier" dated 08 Jul 2016, extra energy is needed for B in circular motion.  The extra energy needed reduces the total power in B.  When B returns from the time dimension, where is this energy when a radiating wire is not in a circular loop (E not circular).

Is the power 14Ptotal the radiated power?

Yes! (but no, read further...)  Because in a circular loop wire antenna, the gap in the loop at the connections is radiating power.  This gap is the part of the wire loop that deviates from a circle.  When B is transformed back to E, E is supposedly circular, a complex sinusoidal, A(cos(i2πft)+isin(i2πft)) because B is a complex sinusoidal.  That part of E that encounters a break in the loop is radiated into space.


When the antenna is a straight wire, one of the components, (Ecos(i2πft or Esin(i2πft)) of the circular E is radiated.  The actual power fraction is Pf=12(12)2=18.

And no!  The initial power fraction of Pf=14 is loss bending the E into a circular wave.  This part of the power is not recovered as long as E remains circular.

In the case of the gap in a circular loop,

Pstr=(θant2π)2 a guess

where θant is the angle subtended by the gap at the center of the loop.  The power fraction Pf that applies to a straight wire antenna does not appear here because the applied E is already circular.  No energy is needed to made B circular.