Antenna Gain
Gain, half-power beamwidth and effective aperture of a parabolic dish antenna from its diameter and operating frequency.
Inputs
Results
- Gain
- – dBi
- Gain (linear)
- –
- Half-power beamwidth
- – °
- Effective aperture
- – m²
- Wavelength
- – cm
Beam visualization
Side view · angle to true scale
Main-lobe pattern · normalized gain vs. off-axis angle
Main lobe approximated as G(θ) = −12 · (θ / HPBW)² dB. Side lobes are not shown.
G = η · (πD / λ)² · HPBW ≈ 70 · λ / D (degrees) · Ae = η · πD² / 4 · λ = c / f. 55–70% is a typical efficiency for a parabolic dish.