All Questions
Tagged with antennas maxwell-equations
10
questions
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2
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141
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Do electromagnetic antennas transmit (unintentionally scatter) when they receive?
My electromagnetic waves professor said any time an electromagnetic signal is received by an antenna, a transmission also occurs.
I have not independently verified this, but I believe it is likely ...
- 115
0
votes
2
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167
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Coaxial Confusion, what really are unbalanced transmission lines? [closed]
Thanks for clicking on my question.
I do not understand how an unbalanced transmission line works.
Take for instance coaxial cable which is the subject of my confusion.
This confusion arises from the ...
- 35
1
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0
answers
62
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How to apply Maxwell's equations to electromagnetic waves? [closed]
You know how antennas work and create EM waves...They oscillate charges which create EM waves
Well I'm not satisfied with that explanation so it would be great if you could use maxwells equation to ...
- 1,189
2
votes
0
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79
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Lossy electromagnetic wave and reactive power
Consider an electromagnetic wave in a lossy medium. This medium has a complex permittivity $\varepsilon_r=\varepsilon_r' +j \varepsilon_r''$ and a wave impedance given by
$$Z=\frac{E}{H}=\sqrt{\frac{\...
- 1,149
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38
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Are there sources for potential wave solutions for which the electromagnetic far-field is zero?
Are there sources for electromagnetic potential propagating wave solutions for $\phi$ and $\overrightarrow{A}$
for which the electromagnetic far-field $\,>\!\lambda\,$ in vacuum is zero $\...
- 465
0
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2
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137
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Where does the energy go to for a charged sphere with pulsing radius?
In the question A charged sphere with pulsing radius the answer says that the charged sphere does not radiate. However, compressing a sphere of charge to a smaller radius requires work, so where does ...
- 465
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1
answer
89
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Electrodynamics confusion - Hertzian dipole
I am studying a course in Electrodynamics and we are just covering retarded potentials and the Hertzian dipole.
In my lecture notes, we have calculated the magnetic vector potential $A$ in the ...
- 1,094
1
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0
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131
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How can we excite transverse magnetic or electric ( TM or TE) modes on metallic mediums?
I would be very thankful if someone can point me at references on explaining theories of excitations for transverse magnetic or electric modes.
In engineering, the literature has plenty of papers on ...
0
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46
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Dipole Receive Antenna: Derivation of circuit representation
Many textbooks cover generation of electromagnetic radiation via transmit antenna and then invoke a reciprocity theorem for the antenna acting as a receiver.
I'm wondering, can you derive the ...
- 912
1
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1
answer
101
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Radiation Pattern for a Dipole Antenna with non-sinusodial forcing voltage
I was wondering, how does one derive the radiation pattern for a dipole antenna if you don't assume a sinusoidal forcing function? It seems this assumption kind of ignores the most important question ...
- 912