NETWORK CODE DGPS POSITIONING AND RELIABLE ESTIMATION OF POSITION ACCURACY

A network reference station approach instead of a single reference station improves the efficiency and reliability of precise GPS positioning, GPS reference stations exist in some countries, and GPS observations are available for users in real-time mode and for post-processing. This paper presents DGPS post-processing positioning with the use of three simultaneous reference stations. The paper shows that when a reference station network is used, it can create pseudo-range corrections for a virtual reference station, located in the vicinity of an unknown station, and improve the accuracy of determined positions. Network reference stations give redundant observations and reduce the impact of some measurement errors. Practical calculations and analysis of accuracy in code DGPS positioning and the validation of standard deviations determined from adjustment are presented for medium-long distances between a rover and reference stations.