Algorithm Study on the Earth Rotation Parameters with the Combination of VLBI and BDS

The earth rotation parameters (ERP) are estimated by MGEX station’ data collected in 2016 from 61 to 91 days with PANDA. The ERP are estimated by processing VLBI data during the same period with VieVS2.2. The results of BDS and VLBI are combined in a weighted way to get the comprehensive ERP value, based on IERS 08C04. The comparisons show that the RMS values of the differences between the series given in this paper and IERS series are 0.249 mas in x-component of polar motion(X-Pole), 0.296 mas in y-component of polar motion(Y-Pole), 0.053 ms in UT1-UTC. The joint calculation of ERP parameters by BDS and VLBI data makes up for the instability of the BDS calculation results and the discontinuity of the VLBI observation, so that the stability and reliability of the results are improved.