Abstract：We assess the orbit quality of BDS GEO and IGSO satellites, based on global navigation satellite system(GNSS) and satellite laser ranging(SLR) observations. When using GNSS observations for BDS orbit determination, the results show that the SLR residuals of C01, C08 and C10 have a certain degree of deviations, and that the values from the satellites are not identical. In combined orbit determination using GNSS and SLR observations, the orbit accuracy with SLR range biases estimated and not estimated are analyzed. The results show that SLR range biases must be estimated for C01 due to a large bias in GNSS-only solution. There is a certain degree of improvement in orbit prediction for C08 and C10, using the combined solution with estimating SLR range, bias or not. In addition, statistics of range biases for C01 is about 50 cm and less than 5 cm for C08 and C10.
