Vertical Accuracy Assessment of Single Frequency DGPS

The Differential Global Positioning System (DGPS) device accuracy specifications may not be achievable by users due to lack understanding of various factors influencing the accuracy and other limitations. DGPS accuracy assessment is done with consideration of different surveying method and different affecting parameters like baseline(LB), Precision Dilution of position(PDOP), Signal-to-Noise ratio(SNR) and occupation time, with the help of results produced by the post-processing analysis. It not only help to find the best condition for survey with addition of mission planning but also provide complete information about the preferred survey method and occupation time. In this study was analysis carried out by using single frequency DGPS mode of acquiring data such as stop-n-go. Analysis was done for relative vertical accuracy Single Frequency DGPS receiver. Main conclusion of the vertical accuracy for single frequency varies with 0.012m in 30 sec for clear sky but in case of obstruction such as near the tree occupation time has to increase 45 sec or more with 0.016m accuracy for baseline<1km.