Reducing Distance Dependent Errors for Real-Time Precise DGPS Applications by Establishing Reference Station Networks

Precise real−time DGPS positioning currently becomes important in many surveying and navigation applications. The implementation of On−The−Way (OTW) ambiguity search algorithms in real−time software packages provides centimeter accuracy over distances of up to a few tens of kilometers between a reference station and mobile users. Distance dependent errors like atmospheric refraction and orbit errors limit the accuracy to 1 to 10 ppm.