Differential GPS (DGPS)

Differential GPSGPSThe Global Positioning System (GPS) is a satellite-based navigation system operated by the U.S. Space Force that prov... (DGPS) is an augmentation technique that improves the accuracy of standard GPS positioning by using one or more ground-based reference stations at precisely known locations. Each reference station compares its GPS-derived position with its surveyed coordinates, calculates the positioning error, and transmits real-time corrections to nearby rover receivers via radio, cellular, or satellite broadcast links. How DGPS worksThe reference station continuously tracks the same satellites as the rover receiver and computes range corrections for each satellite. These corrections account for satellite orbit and clock errors, atmospheric delays, and other common error sources. Because the reference station and rover experience similar atmospheric conditions (within a limited baseline distance), applying the corrections at the rover substantially reduces positioning error from 3-5 meters to 0.5-1 meter. ApplicationsDGPS is widely used in maritime navigation (coast guard broadcast DGPS services provide harbor approach guidance), agriculture (sub-meter guidance for field operations), GISGISGeographic Information Systems (GIS) enable users to analyze and visualize spatial data to uncover patterns, relation... data collection (mapping assets and features), and aviation (approach and landing systems). DGPS bridges the gap between unaided GPS and more precise techniques like RTK. DGPS provides a cost-effective accuracy improvement over standard GPS without the complexity and cost of centimeter-level RTK systems. It remains a practical choice for applications requiring sub-meter accuracy over wide areas.