Definition
GPS and GNSS are closely related terms for satellite positioning, but they are not the same. GPS is one specific system, operated by the United States, while GNSS is the umbrella term for all satellite navigation systems worldwide, including GPS.
In everyday speech, people often say GPS to mean any satellite positioning. In technical and surveying contexts, GNSS is the more accurate term because modern receivers use several systems at once for better reliability.
In simple terms, GPS is one satellite system, and GNSS is the whole family of them, including GPS.
How It Works
Both GPS and GNSS work by having satellites broadcast signals that receivers use to calculate position. A receiver measures how long signals take to arrive from several satellites and combines those distances to determine its location on Earth.
A GNSS receiver can listen to multiple systems, such as GPS, Galileo, GLONASS, and BeiDou, at the same time. Using more satellites improves accuracy and reliability, especially in challenging environments, which is why surveying favours GNSS over GPS alone.
Applications
GPS and GNSS are used in navigation, surveying, mapping, agriculture, and construction. In precise work such as surveying and drone mapping, GNSS receivers combine multiple systems and correction techniques to achieve centimetre-level positioning for control points and measurements.
Benefits
- Reliable positioning anywhere on Earth.
- Greater accuracy by using multiple systems.
- Better performance in difficult environments.
- Centimetre precision with correction methods.
- A foundation for georeferencing captured data.
Related Terms
- GNSS (Global Navigation Satellite System)
- GPS Coordinates
- RTK (Real-Time Kinematic)
- Georeference
Frequently Asked Questions
What is the difference between GPS and GNSS?
GPS is the specific United States system, while GNSS is the general term for all satellite navigation systems, including GPS.
Is GPS a type of GNSS?
Yes. GPS is one of several systems that together make up GNSS.
Why does surveying use GNSS instead of GPS?
GNSS receivers use multiple systems at once, improving accuracy and reliability, which matters for precise surveying.
How accurate is GNSS positioning?
Standard positioning is accurate to a few metres, but correction techniques such as RTK can reach centimetre level.
About Track3D
Track3D helps teams turn precise GNSS-referenced data into accurate digital twins. Learn more at Track3D.
