Use this electronics calculation for a first-pass component, converter, signal, motor, or sensor estimate when the stated operating conditions and units match the device data.

Aperture area (m²)

Required number input.

Wavelength (m)

Required number input.

Aperture efficiency

Optional number input.

Compute the linear antenna gain as G = 4 x pi x A x eta / lambda^2 with aperture efficiency eta between zero and one, defaulting to 0.55. The tool evaluates the supplied inputs together and returns the named outputs below; it does not infer omitted operating conditions or change the units shown.^[1]

Antenna gain (ratio)

The resulting antenna gain returned as a number.

• Antenna formulas assume stated frequency, impedance match, polarization, efficiency, aperture, and propagation geometry. Nearby objects, ground, feed loss, multipath, regulatory averaging, near-field conditions, and pattern variation can make free-space or ideal-aperture results inaccurate.
• Use finite inputs in the displayed units and preserve more precision than the final presentation requires. Independently verify safety-critical, financial, compliance, or production decisions.

Check the result against the current datasheet and worst-case operating corners, then verify the circuit or measurement with simulation and bench testing where failure matters.

• Effective Aperture

  Compute the antenna effective aperture in square meters as Ae = lambda^2 x G / (4 x pi); wavelength and linear gain must be positive.

• Parabolic Dish Gain dBi

  Compute parabolic dish gain in dBi as 10 x log10(eta x (pi x D / lambda)^2); eta defaults to 0.55.

• Directivity From Gain

  Recover antenna directivity as directivityDbi = gainDbi - 10 * log10(efficiencyFraction), with efficiency defaulting to 0.6.