DGPS / GNSS Systems

Differential Global Positioning System (DGPS)

An enhancement to Global Positioning System providing an improved location accuracy, from the 15m nominal GPS accuracy to about 10cm, at best.

DGPS uses an amalgamation of receivers and satellites that –

• Significantly improve the rate of accuracy from 100s of metres, to centimetres, to millimetres
• DGPS leverages network fixed ground based reference stations in familiar locations.
• The base station draws a comparison between its own location, to the one computed from the GPS receiver.
• The difference is then broadcasted as a correction to the user. The correction signals can either be broadcasted via the ground stations, or from the additional satellites. These privately owned services usually require a user subscription.

The Differential GPS can replace an entire month of manual work with traditional methods. The labour saving is substantial, however, at the same time, tasks that were previously rendered impossible like predicting earthquakes before they occur, have now been made possible.

GNSS Systems

GPS/GNSS system studies the use of GPS and GNSS signals, using a GPS/GNSS system/ receiver and antenna to decide the boundary, form, position of objects and points in space relative to other boundaries, forms, and points. This ousts the traditional opticals and mechanical processes of surveying that rely solely on the theodolites and distance measuring equipment that leverage linear and angular measurements, and the application of trigonometry and geometry.