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Calcimator

Antenna Gain Calculator

Calculate antenna gain in dBi from aperture dimensions, frequency, and efficiency. Includes beamwidth and effective aperture area.

Inputs

MHz
m
m
%

Results

Gain

11.92 dBi

Horizontal Beamwidth

46.63°

Gain (Linear)15.6×
Wavelength0.3331 m
Vertical Beamwidth46.63°
Effective Aperture0.1375 m²
Physical Aperture0.25 m²
How to Use This Calculator
  1. Enter the center frequency (MHz or GHz).
  2. Set aperture width and aperture height in meters (for parabolic dish or horn antennas).
  3. Enter antenna efficiency (0.55-0.70 is typical for a well-designed reflector).
  4. Review calculated gain in dBi and linear scale, effective wavelength, and half-power beamwidths.
  5. Use gain value in link budget calculations to determine received signal strength.

How the result changes with Frequency

FrequencyGainHorizontal Beamwidth
10,00132.84 dBi4.2°
35,00143.72 dBi1.2°
65,00049.1 dBi0.65°
90,00051.92 dBi0.47°

What each input means

Frequency
Operating frequency of the antenna in megahertz
Aperture Width
Physical width of the antenna aperture in meters
Aperture Height
Physical height of the antenna aperture in meters
Antenna Efficiency
Antenna aperture efficiency (typical parabolic dish: 50-65%)

How this is calculated

Formula

G = (4π × η × A) / λ²

Worked example, using the default values

  1. Identify Input Parameters
    4 parameters
    Frequency = 900, Aperture Width = 0.5, Aperture Height = 0.5, Antenna Efficiency = 55 = 4 input(s) provided
  2. Calculate Gain
    Gain
    11.92 = 11.92
  3. Calculate Horizontal Beamwidth
    Horizontal Beamwidth
    46.63 = 46.63
  4. Calculate Gain
    Gain
    15.6 = 15.6
  5. Calculate Wavelength
    Wavelength
    0.3331 = 0.3331

Engine last updated . Checked against 3 independently-derived tests — how we verify calculators.

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