Electric dipole antenna voltage

AI Thread Summary
To solve the problem of electric dipole antenna voltage, it's essential to integrate the current distribution to find the potential. The discussion highlights the importance of understanding radiation resistance, particularly for a half-wave dipole, which is necessary for accurate calculations. Additionally, knowing the magnetic field allows for the determination of the electric field and the Poynting vector, which represents power per unit area. The effective area of the antenna also plays a crucial role in calculating the power input. Finally, the relationship P = V^2/R can be used to derive the voltage once the power is known.
loki4000
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Homework Statement


Greetings.
Can someone give me hint how to solve following problem:
rbdvte.jpg

Homework Equations


From my understanding, you need following formula to solve problem:
200picj.gif

and then potential can be obtained by integrating over the current distribution.
But right now these foormuas really confuse me (have probem understanding what is going on in picture). So I don't understand how to find current distribution.

The Attempt at a Solution


My guess is:
potential = (int) current distribution
V = I0(z)e^iwt
 
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I don't think your suggested method is of any avail. That's for determining the strength of an e-m signal at a distance r away from the antenna.

Also: antennas have radiation resistance R. You need to come up with that resistance. You can look that up most anywhere for your half-wave dipole. You need to assume that your receiving antenna is also terminated in this resistance.

Then: you're given the B field so you can determine the E field and hence the Poynting vector which is power per unit area. So you also need to look up the effective area for your antenna.

Once you have the power input to your antenna you just go P = V^2/R to get your V.
 
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