# Antenna Gain - Gain Comaprison(Transfer) Method

1. Nov 10, 2013

### jegues

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 $$G_{smallhorn} = 8dB$$ Obtain the gains of the other two antennas using gain-comparison method.

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.

Use the approximate formula,

$$D = \frac{26000}{HPBW_{E} * HPBW_{H}}$$

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.

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?

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