This study presents the generation and accuracy assessment of predicted orbital ephemeris based on satellite laser ranging (SLR) for geostationary Earth orbit (GEO) satellites. Two GEO satellites are considered: GEO-Korea Multi-Purpose Satellite (KOMPSAT)-2B (GK-2B) for simulational validation and Compass-G1 for real-world quality assessment. SLR-based orbit determination (OD) is proactively performed to generate orbital ephemeris. The length and the gap of the predicted orbital ephemeris were set by considering the consolidated prediction format (CPF). The resultant predicted ephemeris of GK-2B is directly compared with a pre-specified true orbit to show 17.461 m and 23.978 m, in 3D root-mean-square (RMS) position error and maximum position error for one day, respectively. The predicted ephemeris of Compass-G1 is overlapped with the Global Navigation Satellite System (GNSS) final orbit from the GeoForschungsZentrum (GFZ) analysis center (AC) to yield 36.760 m in 3D RMS position differences. It is also compared with the CPF orbit from the International Laser Ranging Service (ILRS) to present 109.888 m in 3D RMS position differences. These results imply that SLR-based orbital ephemeris can be an alternative candidate for improving the accuracy of commonly used radar-based orbital ephemeris for GEO satellites.

1. INTRODUCTION
 1. INTRODUCTION
 2. SATELLITE ORBIT DETERMINATION
  2.1 Overview of GK-2B
  2.2 SLR-based Orbit Determination
 3. ORBITAL EPHEMERIS GENERATION ANDVALIDATION
  3.1 GK-2B Ephemeris Validation
  3.2 Compass-G1 Ephemeris Validation
 4. CONCLUSIONS
 REFERENCES

• Hyungjik Oh(Department of Astronomy, Yonsei University)
• Eunseo Park(Korea Astronomy and Space Science Institute)
• Hyung-Chul Lim(Korea Astronomy and Space Science Institute)
• Sang-Ryool Lee(Korea Aerospace Research Institute)
• Jae-Dong Choi(Korea Aerospace Research Institute)
• Chandeok Park(Department of Astronomy, Yonsei University) Corresponding Author