What is the primary function of Differential GPS?

The primary function of Differential GPS (DGPS) is to enhance the accuracy of Satellite-based GPS by using ground-based stations to correct the GPS signal. DGPS works by having fixed reference stations that know their precise location. These stations can detect any discrepancies between their known location and the location reported by GPS satellites. The reference stations then broadcast a correction signal to nearby GPS receivers, allowing for improved accuracy and reliability of the positioning information.

This method is particularly valuable in applications that require high precision, such as marine navigation, surveying, and aviation. The corrections can reduce the positional error from the standard GPS accuracy of about 10-20 meters to as little as 1 meter or less, depending on conditions and the specific implementation of DGPS being used.

The other functions mentioned, such as providing altitude information, increasing GPS signal strength, or calculating wind speed, are not primary roles of DGPS. While altitude can be derived from GPS data, it is not its primary function, and GPS signal strength is generally a separate concern from differential corrections. Likewise, calculating wind speed is unrelated to the primary function of DGPS, which focuses solely on enhancing positional accuracy.