Increasing of DGPS accuracy by use of Kalman filtering

Differential GPS (DGPS) is the system used for improving accuracy in GPS position and velocity estimation. Measurements can be obtained in real time with a high level of accuracy by means of use DGPS for task the vehicle tracking, dispatching, location, navigation, etc. In this paper we present a modified Kalman filter for DGPS to achieve an accurate estimation of the position and velocity. The proposed and realized algorithms in DGPS system can be implemented by low cost commercial C/A code GPS modules. With the help of Kalman filter the reducing of the anti-common errors between the users and reference station has been achieved. Two variants of the Kaleman filters have been investigated. It is presented the experimental testing of the performance of DGPS with Kalman filtering. The used filtering procedure has shown the possibility to reduce the anti-common errors. The proposed and investigated procedures of Kalman filtering could be used for better positioning in the different navigation and positioning applications.