Regional and Global Navigation Satellite Systems

A satellite-navigation system uses signals from satellites to help receivers determine their position and time. The main distinction is geographical: a regional system is designed to serve a defined part of Earth, whereas a global system is designed to provide navigation services worldwide.

Geographical coverage

The distinction concerns the system's intended service area, not the nationality of its users or the location of its controlling agency.

• A regional navigation satellite system concentrates coverage on a particular country and its surrounding region rather than providing worldwide service.
• A global navigation satellite system uses a satellite constellation arranged to provide worldwide coverage, including locations far from the country operating it.
• Coverage describes where a service is designed to be available; it does not by itself indicate how accurately a receiver can determine its position.

India's regional system and global examples

Navigation with Indian Constellation (NavIC), also known as the Indian Regional Navigation Satellite System, is India's independent regional navigation system.

• NavIC's primary service area covers India and approximately 1,500 km beyond its boundary. It is therefore regional, not a worldwide equivalent of GPS in geographical reach.
• The United States' Global Positioning System (GPS) is a global system, designed to provide positioning, navigation and timing services worldwide.
• Other global systems include Russia's GLONASS, the European Union's Galileo and China's BeiDou.

How to interpret the distinction

Coverage and accuracy are separate characteristics. A regional system can provide precise navigation within its intended service area without being a global system.

• A regional service boundary should not be understood as a sharp line beyond which no satellite signal can ever be received; signal reception and the specified service area are different concepts.
• Multi-constellation receivers can use signals from more than one navigation system, but this does not change each system's own geographical scope.