High Precision GPS／BDS Data Processing and Precision Contrast Analysis Based on GAMIT10.61

The paper deals with the GPS data and BDS data of eight station CORS in Chongqing using GAMIT10.61 software, and mainly from the baseline repeatability, coordinate time series, combined adjustment in three aspects analyzed the calculation results of GPS and BDS.Results show that GPS results is better than BDS, and the difference between the single BDS and single GPS solution in the horizontal direction is less than 0.7cm, and 1cm～3 cm in the vertical; the BDS baseline repeatability is 1.39mm+0.205mm×10^-8 in the north-south direction, 3.10mm+0.252×10^-8in the east-west direction, 7.81mm+2.001×10^-8in the vertical direction, 2.13mm+0.384×10^-8 in the baseline length, calculation precision can meet the high precision data processing requirements using GAMIT 10.61.