Satellite Dish Alignment

The satellites essential for TV and radio reception orbit the Earth parallel to the equator at an altitude of 35,800 km (geostationary orbit). At this altitude, the orbital speed matches the Earth's rotational speed. For an observer on Earth, such a satellite appears to remain stationary in the sky, i.e. fixed in position.

Because of this phenomenon, a satellite dish on Earth can be aligned to this constant position in the sky. Note, however, that the orbital positions of geostationary satellites are given in degrees east and west longitude, e.g. 19.2° East or 12.5° West (based on the Greenwich Meridian, which is also the Prime Meridian). A meridian (longitude) runs north-south from pole to pole and is perpendicular to the equator. An orbital position of 19.2° East therefore means an angle of 19.2° eastward from the Prime Meridian, at whose intersection with the equator the satellite is located.

Azimuth and Elevation Angles

Thus, two adjustments are necessary for aligning a satellite dish: a horizontal swivel (left-right) for the azimuth angle and a vertical swivel (up-down) for the elevation angle. The azimuth is specified as the angle from north via east to the direction of the incoming satellite signal. For example, in Göttingen, the azimuth for ASTRA 19.2° East is about 168°. The elevation (i.e. the altitude angle) here is about 30°.

Azimuth angle

Elevation angle