Helps about measuring the power of antennas?

Discussion in 'Wireless & RF Design' started by thanhvu94, Oct 1, 2016.

  1. thanhvu94

    Thread Starter New Member

    Oct 1, 2016
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    Hello,

    I'm doing a project about aquatic drone and we have 2 antennas on it. We want to measure the power of the two antennas and compare with each other to find out whose signal is stronger. Can you give me some ideas about this? (circuit, website, books...)

    Thank you so much
     
  2. blocco a spirale

    AAC Fanatic!

    Jun 18, 2008
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    If you have two antennas and you just want to know which one performs the best, i.e. provides the best range, there is an obvious way to test this, isn't there?
     
  3. Papabravo

    Expert

    Feb 24, 2006
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    Antennas are passive devices. They have no way to create power, so your question is literally meaningless. What you might have meant was that, depending on their geometry, one antenna might have more gain than another one. That is it might radiate a signal more effectively than another one. Is that what you meant?
     
  4. thanhvu94

    Thread Starter New Member

    Oct 1, 2016
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    Sorry for my confusing question. It is exactly what I meant, compare the signal strength of 2 antennas.
     
  5. Papabravo

    Expert

    Feb 24, 2006
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    So what you have to do is measure the radiated field strength in 3 dimensions as the antenna is activated with a test signal.

    Like this or similar:
    http://www.idiytool.com/wholesale/l...-tester.html?gclid=CMqAyf-mvM8CFctbhgodZSkHAg

    Now I have never used such an instrument so I cannot vouch for it's efficacy. You could also use a receiver with a field strength meter to make a crude comparison at a single point.
     
  6. thanhvu94

    Thread Starter New Member

    Oct 1, 2016
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    Thank you for your reply, but we want to find a way/module/circuit that can measure and compare automatically (not manually). Do you still have any ideas? I'm new to this field.
     
  7. Papabravo

    Expert

    Feb 24, 2006
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    The problem with automated measurement is that you have to create a grid of measurement points with an instrument at each point, or an instrument that can be moved to each measurement point. No matter how you slice it this will be an expensive proposition. The only other way you could approach this problem is to use EZNEC or similar software to simulate the antenna. This will give you theoretical radiation patterns and allow two antennas to be compared.

    https://www.eznec.com/
     
  8. BR-549

    Well-Known Member

    Sep 22, 2013
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    An S meter.
     
  9. Papabravo

    Expert

    Feb 24, 2006
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  10. DickCappels

    Moderator

    Aug 21, 2008
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    It might help if you give us a clear idea of what you want to make and what it does.

    It is starting to sound like it might be a direction finder application, can not tell from the information given until now.

    Are your antennas transmitting or are they receiving?
     
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