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Antenna Gain - Gain Comaprison(Transfer) Method

  1. Nov 10, 2013 #1
    1. The problem statement, all variables and given/known data

    1) H-plane patterns of rectangular microstrip antenna, open-ended waveguide antenna and small horn antenna are measured and shown in the table below. Assuming the small horn antenna as reference antenna with a gain of [tex]G_{smallhorn} = 8dB[/tex] Obtain the gains of the other two antennas using gain-comparison method.

    attachment.php?attachmentid=63826&stc=1&d=1384109261.jpg

    2) Using the gains derived in problem 1 and assuming f = 10.5GHz, obtain the effective area for the rectangular microstrip and open-ended waveguide antennas.

    3) Calculate the aperture efficiency of the microstrip and open-ended waveguide antennas using the results of problem 2. (The physical aperture of the rectangular microstrip antenna is 0.8×1.25 cm^2 and the open-ended waveguide has a physical aperture size of 1×2.25 cm^2)

    4) The E- and H-plane patterns of rectangular microstrip antenna and open-ended waveguide antenna are measured and the HPBWs are shown in the table below.

    attachment.php?attachmentid=63827&stc=1&d=1384109263.jpg

    Use the approximate formula,

    [tex]D = \frac{26000}{HPBW_{E} * HPBW_{H}}[/tex]

    to calculate the gains of the antennas (assuming lossless antennas). Compare these results with the results obtained in problem 1 and determine which one is more exact if they were not equal.


    2. Relevant equations



    3. The attempt at a solution

    I did my solution attempt in Mathcad so that if I have to change any of the parameters I can quickly solve the problem again.

    Since there is no simple way to convert my math to text or latex I've attached an image of my solution attempt below.

    attachment.php?attachmentid=63828&stc=1&d=1384109263.jpg

    Questions

    My calculated gains from part 1) don't seem to be lining up with the gains from part 4).

    Am I correct to use the power values in Watts and not dB in part 1)?

    Is the approximate formula in 4) meant for HPBW values given in radians?
     

    Attached Files:

  2. jcsd
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