Abstract: Aiming at the current stage of BeiDou system in BDS-3+BDS-2 hybrid service, this paper analyzes the data processing model of BDS network, and establishes a kind of high-precision engineering surveying network based on BDS-3+BDS-2 dual-frequency data for the application test. Four CORS stations that simultaneously support BDS-3+BDS-2 and GPS dual-frequency data are selected to lay high-precision engineering surveying network for data processing, and comparative analysis and evaluation are carried out in terms of the accuracy of phase observation values, standardized root-mean-square error after checking, quality of baseline vectors, repeatability of the baseline, and results of the net adjustment point coordinates. The experimental results show that: using the B1I and B3I dual-frequency data of BDS-3+BDS-2 to establish a high-precision engineering surveying network, the results of the obtained point coordinates are millimeter lever in horizontal direction and millimeter to decimeter level in vertical direction different from the corresponding results of the L1 and L2 dual-frequency data of GPS, which is effective to be applied to the high-precision engineering surveying network.

Key words: BeiDou system, dual-frequency data, GPS system, baseline solving, network adjustment, high-precsion engineering surveying network