Satsig logo

How to make inclinometer.

Inclined orbit operation.

Dish pointing.

Focal length of parabola.

Satellite TV.

Antenna panel alignment.

Satellite beam design.

Sub reflector adjustment.

Use rear side struts.

VSAT antenna anti-icing.

Satellite link budget.

Dish interference: Site shielding.

Correcting VSAT dish distortion.

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.
. Antenna gain. dBi means relative to an isotropic omni-directional antenna.
. The antenna gain shown in top line of the results is the on-axis gain.

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.

Diameter of your satellite dish Freq-uency Effic-iency
0.6 to 0.8
metres GHz  

dB contour
down
Full beam width
deg.
Half beam width
degr.
Gain
dBi
0 0 0
0.25
0.5
1
2
3
4
4.5
5
6
7
10
15
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

Page last updated 10 Oct July 2014