Calculating the total power received by an antenna

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Discussion Overview

The discussion revolves around calculating the total power received by a radar antenna that transmits at 50kW and reflects off an aircraft at a distance of 100km. The context includes theoretical calculations involving electromagnetic wave propagation and reflection, with specific parameters provided for the antenna and the environment.

Discussion Character

  • Homework-related, Mathematical reasoning

Main Points Raised

  • One participant presents a calculation scenario involving a radar antenna transmitting 50kW at 10 GHz and asks for help in determining the total power received after reflection from an aircraft.
  • The participant notes that only 1% of the transmitted power propagates back towards the antenna after reflection.
  • Another participant requests to see the work done so far to provide guidance on the calculations.
  • A third participant acknowledges the attachment of a PDF file containing the participant's attempts at solving the problem.
  • There is a follow-up from another participant indicating they will review the attached file for further insights.

Areas of Agreement / Disagreement

The discussion remains unresolved, with no consensus on the calculations or methods presented. Participants are seeking clarification and guidance rather than reaching a definitive conclusion.

Contextual Notes

Limitations include the need for clarity on the calculations attempted by the original poster and any assumptions made regarding the propagation of the radar waves and the characteristics of the aircraft.

enginej
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Thread moved from the technical forums, so no Homework Template is shown
A radar antenna transmits 50kW at 10 GHz. Assume transmission is in a narrow beam, 1m^2 in area, and that within the beam, waves are plane waves. The wave is reflected from an aircraft but only 1% of the power propagates i the direction of the antenna. If the airplane is at a distance of 100km,

Calculate: The total power received by the antenna. Assume Permittivity and permeability of free space and conductivity of 10^-7 S/m.

ANSWER: The answer is 0.266 W (I can't seem to get it.)
 

Attachments

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Can you show what you have attempted, so far? Then we will make suggestions to guide you.
 
scottdave said:
Can you show what you have attempted, so far? Then we will make suggestions to guide you.

Thanks for the interest, I already attached the PDF file of my work, let me know if you can't see it.
I also attached a second attempt of the problem, to this post.
 

Attachments

I missed that there is a file attached. I will take a look.
 

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