GNSS Skyplot Coordinates Explained

A GNSS skyplot visually represents the positions of satellites relative to an observer on the ground.

Understanding Skyplot Coordinates

Skyplots typically use a two-dimensional coordinate system based on the observer's location and orientation:

• Azimuth (Az): This angle measures the satellite's horizontal position along the horizon, measured clockwise from North (0 degrees). It ranges from 0 to 360 degrees.
• Elevation (El): This angle measures the satellite's vertical position relative to the horizon. An elevation of 0 degrees means the satellite is on the horizon, and 90 degrees means it is directly overhead (at the zenith).

Identifying Satellite Orbit Representation

The skyplot shows where satellites appear in the sky. The Elevation angle is crucial as it directly indicates how high a satellite is above the observer's horizon. Combined with Azimuth, it pinpoints the satellite's location.

While Right Ascension and Declination are celestial coordinates, GNSS skyplots primarily use the local, observer-based Azimuth and Elevation system.

Conclusion

The Elevation angle represents how high a satellite appears in the skyplot relative to the horizon, forming one of the key coordinate pairs used.