Radiation vector for a short dipole near a perfect magnetic conductor


by Bromio
Tags: dipole, radiation
Bromio
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#1
Nov13-12, 06:03 AM
P: 61
Hi there.

If I wanted to calculate the radiation vector (in z > 0) produced by a short dipole with uniform current Io (+z direction) on a infinite perfect electric conductor (plane z=0), I'd have to apply the images method. So I'd have to calculate the radiation vector produced by two short dipoles, one in z > 0 and one in z < 0, with currents Io.

However, if we change the perfect electric conductor by a perfect magnetic conductor, how can I apply the images method?

Thank you.
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berkeman
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#2
Nov13-12, 12:12 PM
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Quote Quote by Bromio View Post
Hi there.

If I wanted to calculate the radiation vector (in z > 0) produced by a short dipole with uniform current Io (+z direction) on a infinite perfect electric conductor (plane z=0), I'd have to apply the images method. So I'd have to calculate the radiation vector produced by two short dipoles, one in z > 0 and one in z < 0, with currents Io.

However, if we change the perfect electric conductor by a perfect magnetic conductor, how can I apply the images method?

Thank you.
What's a perfect magnetic conductor?
Bromio
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#3
Nov13-12, 02:50 PM
P: 61
It's an idealization.

PEC (Perfect Electric Conductor): [itex]\hat{n}\times\vec{E}=0 [/itex] and [itex]\hat{n}\times\vec{H}=\vec{J}_s[/itex].

PMC (Perfect Magnetic Conductor): [itex]\hat{n}\times\vec{E}=-\vec{M}_s [/itex] and [itex]\hat{n}\times\vec{H}=0[/itex].

Thank you.

Enthalpy
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#4
Nov14-12, 04:48 PM
P: 660

Radiation vector for a short dipole near a perfect magnetic conductor


At very low frequency, mumetal of permalloy are good magnetic conductors.

It would change the sign of the current in the image. Opposite current achieve zero magnetic field at the magnetic conductor, while same currents achieve zero electric field.
Bromio
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#5
Nov20-12, 05:06 AM
P: 61
Hi.

I understand what you say, but, in that case, radiation vector is 0 (because currents are opposite), isn't it?

Thank you.


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