Calculating High Frequency Earth Rotation Parameters Using GPS Observations and Precision Analysis

Abstract

The earth rotation parameters (ERP) have a strong correlation with the migration and movement of earth materials, extraterrestrial world gravity and the load deformation of solid earth. On the other hand, ERP is a very important parameter when converting the earth reference system to the celestial reference system. But the International Earth Rotation Service(IERS) and International GNSS Service(IGS) only release one ERP per day which cannot satisfy the user who need the high frequency of ERP. However, there are amounts of Global Positioning System(GPS) data which can be used to estimate ERP with high time resolution and long time span. Based on this, global uniformly distributed 40 IGS stations are selected to estimate ERP by using the data of the Day of Year(DOY) from 1 to 180 of 2015 with Bernese soft 5.0. In the first part, 24 h resolution of ERP is estimated. The precision of polar motion $x_{p}$, $y_{p}$ can be achieved at the precision 0.289, 0.245 mas while the precision of UT1-UTC can be achieved at 0.0342 ms which are made a difference with the results of IGS. In the last part of the paper, the 2 h resolution of ERP are estimated and high frequency time series are got. The precision of high frequency polar motion $x_{p}$, $y_{p}$ can be achieved at the precision 0.754, 0.688 mas and the precision of high frequency UT1-UTC can be achieved at 0.1050 ms which are made a difference with the results of IGS at UTC 12:00. The high frequency results have lower precision and stability compared with 24 h resolution results, but still in the acceptable range. Both the results of 24 h resolution and high frequency series have different degrees of systematic deviation. The research above can provide a reference for calculating ERP using BeiDou observations.