The coming years will see two new GNSS (Galileo and BeiDou), and two RNSS (QZSS and NavIC), reach full operational capability. In parallel, the modernization of existing GNSS (GPS and GLONASS) is also well underway. Thus, in just a few years there will be four global and three regional satellite navigation systems, and more than 100 satellites providing open access to more accurate and reliable PNT services, including through the use of multiple frequencies (European GNSS Agency 2019). According to the recent trends, Korea has a plan to develop and build Korea Positioning System (KPS) based on the 3rd Basic Plan for Promotion of Space Development in order to guarantee the stability and improve the accuracy of satellite navigation service. The space segment of KPS will be composed of 3 GEO and 4 IGSO satellites (Ahn et al. 2019). In order to meet the specification of User Equipment Range Error (UERE) of KPS, Precise Orbit Determination (POD) techniques for IGSO and GEO satellites should be developed. In this paper, the preliminary research on the POD technique for KPS satellites was done. In this research, a kinematic and a dynamic orbit determination technique were studied, and a code and carrier phase measurement-based techniques were also considered. Finally, the feasibility of the developed technique was checked by using the QZSS measurements in the International GNSS Service (IGS) networks.

Keywords: GNSS, KPS, POD, IGSO, GEO