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Satellite beam design

Antenna beamwidth calculator

Enter the diameter of your parabolic dish in m (metres) and the operating frequency in GHz (Gigahertz)

A typical VSAT is 1.2m diameter and transmits at 14 - 14.5 GHz

The calculation results are:

  • The total side to side beamwidth of the antenna main beam.
  • Half the side to side beamwidth, if you are concerned to determine the offset angle from the beam centre.
  • The on-axis gain, relative to an isotropic omni-directional antenna.

The results are increasingly approximate beyond the -3 dB contour. The first null may appear at an angle off the boresight similar the the -3 dB full beamwidth.

Default values:
Maximum main beam gain calculation assumes an efficiency of 0.65
The shape of the main beam assumes parabolic illumination with level at dish edge = -10 dB down.

Any problems or comments, please e-mail me Eric Johnston   This calculator is copyright 2007 Satellite Signals Ltd

Original : 10 Oct 2007.   Amended 9 April 2012 to include the possibility of altering the efficiency, in the range 0.6 to 0.8

Diameter of your satellite dish

Frequency

Efficiency
0.6 to 0.8
metres GHz  

dB contour
down
Full beamwidth
degrees  
Half beamwidth
degrees  
Gain
dBi
0 0 0
0.25
0.5
1
2
3
4
4.5
5
6
7
10
15

Page last updated 20 April 2013, 12 July 2013