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Tool 02

Reflector Antenna

Calculate reflector antenna efficiency, gain, beamwidth, aperture area, and related reference values. Compare design changes with frequency or diameter sweeps.

Parameters

Enter reflector diameter, aperture efficiency, and operating frequency. Use the advanced beamwidth factor when you need to match a specific dish model or taper assumption.

Frequency
Reflector Diameter
Aperture Efficiency
%
Advanced Settings
Beamwidth Factor K
deg·D/λ

HPBW ≈ K·λ/D. The default rough estimate for a typical parabolic dish is 70.

Sweep Graph

Custom Data Step applies to Linear X scale; Log X uses automatic logarithmic points.

Reference Values

Frequency [GHz]
10.000
Diameter [m]
1.000
Wavelength [mm]
29.979
Physical Aperture [m²]
0.785
Efficiency [%]
60.000

Formulas

Wavelength

Calculate free-space wavelength from frequency.

λ=cf\lambda = \frac{c}{f}

Physical Aperture

Calculate the physical circular aperture area from reflector diameter.

A=π(D2)2A = \pi\left(\frac{D}{2}\right)^2

Effective Aperture

Effective aperture area after applying aperture efficiency.

Ae=ηAA_e = \eta A

Antenna Gain

Calculate linear gain from efficiency, diameter, and wavelength.

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

dBi Conversion

Convert linear gain to dBi.

GdBi=10log⁡10(G)G_{dBi} = 10\log_{10}(G)

HPBW

Estimate HPBW using beamwidth factor K.

HPBW≈KλDHPBW \approx K\frac{\lambda}{D}

Beamwidth factor K is an empirical factor based on illumination and edge taper; the default is 70.