Application of COMPASS/GPS dual-mode differential positioning technology in the Qinghai-Tibet line

GPS positioning equipment of the foreign manufacturer was used in most of China´s railway system. There are still some problems across the board to rely on the GPS system. In order to achieve better positioning, COMPASS/GPS dual-mode differential positioning was used and tested in the Qinghai-Tibet line. The test data analysis showed that, COMPASS/GPS dual-mode system is significantly better than GPS single system in reliability, availability, security and positioning accuracy.