The
Antenna Pointing Guide determines the required
azimuth and elevation angles to point an
antenna at a geostationary satellite. It
applies to uplink DCP antennas and receive
site (DRGS) parabolic antennas. The following
are needed:
- Latitude of Site
- Longitude of Site
- Equatorial Longitude of the Satellite
(contact Satellite Agency for this value)
1. Subtract
the site longitude from the satellite longitude
to determine the relative ground longitude.
If the result is negative, the site is West
of the satellite. Remember this for step
3.
Example: The satellite is positioned at 135 deg.
longitude, and a site is located at 77 deg.
longitude, 39 deg. latitude, then 135 -
77 = 58 degrees relative longitude.
2. Look
at the nomogram and find the position that
corresponds to the relative longitude and
the site latitude. From this intersection,
read the “A” curves for azimuth
and read the “e” curves for
elevation.
Example: Find the point on the nomogram that corresponds
to 58 degrees relative longitude (computed
in step 1) and 39 degrees latitude. The
values for the elevation and azimuth are:
e = 16 deg
A = 68 deg
3. Identify
what quadrant the site is located in relative
to the satellite and use the chart to adjust
the Azimuth
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