Geopositioning

Geopositioning refers to the process of determining the geographic location of a person, device, or object on Earth. It typically expresses position as coordinates (latitude, longitude, and sometimes altitude) within a coordinate reference system, along with an estimate of positional accuracy and time.

Primary technologies: Global Navigation Satellite Systems (GNSS) such as GPS, GLONASS, Galileo, and BeiDou provide global positioning data. Augmented systems (DGPS, SBAS) improve accuracy. Other methods include Wi‑Fi-based positioning and cellular tower triangulation, IP geolocation, Bluetooth beacons, and indoor positioning using inertial sensors. Geopositioning may also involve georeferencing non-spatial data to a map.

Accuracy and sources of error: Accuracy depends on receiver, environment, and corrections. GNSS is affected by clock and orbital errors, signal multipath, atmospheric delays. Corrections like RTK or SBAS provide centimeter to meter level accuracy. In some contexts, indoor or urban canyon environments reduce accuracy.

Coordinate systems and data formats: Position is expressed in a coordinate reference system, commonly WGS 84 for global data or local CRSs. ISO 6709 defines textual representations of geographic coordinates, and data formats such as NMEA 0183, RINEX, or GeoJSON are used to store or transmit geoposition data.

Applications and privacy: Geopositioning underpins navigation, mapping, logistics, emergency response, agriculture, and autonomous systems. Location data raises privacy and security concerns; many jurisdictions require consent, data minimization, and safeguards.