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Parabolic Antenna Gain

Gain of a dish antenna rises with aperture area and falls with wavelength, scaled by aperture efficiency.

Formula

G=η(πDλ)2G = \eta\left(\dfrac{\pi D}{\lambda}\right)^2

Variables

GGain (ratio)
ηAperture efficiency (≈0.55)
DDish diameter (m)
λWavelength (m)

Example

1 m dish at λ 0.03 m, η 0.55: G ≈ 0.55×(π×1÷0.03)² ≈ 6030 (≈38 dBi)

Did You Know?

Doubling a dish’s diameter quadruples its gain, so weather-radar and satcom performance improves fast with antenna size — limited only by what fits in the nose radome.

antennaparabolicgaindish

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