A receiver obviously uses a source to obtain the data that you will eventually use to measure and tell you where you stand.
The receiver receives this data via satellite(s). A few examples of where the receiver gets this data from are;
- GPS (constellation of America)
- GLONASS (constellation of Russia)
- Galileo (constellation of the European Union)
- Beidou (constellation of the Republic of China)
GNSS (Global Navigation Satellite system)
GNSS stands for Global Navigation Satellite System and is the standard generic term for satellite navigation systems that provide autonomous geospatial positioning with global coverage. This term includes for example GPS, GLONASS, Galileo, Beidou and other regional systems. GNSS is a term used worldwide The advantage of access to multiple satellites is accuracy, redundancy and availability at all times.
When you can receive multiple constellations simultaneously through your receiver, it is called a GNSS receiver. This ensures that you can work even more accurately than when you can only use one constellation. It is a significant difference.