Ho Yun/Changdon Kee/Doyoon Kim
International Journal of Aeronautical and Space Sicences, vol. 12, no. 3, pp.274-282, 2011

Abstract : This paper presents the master plans and preliminary test results of Korean Wide Area Differential GPS (WADGPS) development project which is promoted by Korean government 2010 to 2014. Korean government developed the National GNSS Master Plan to support and coordinate the GNSS development in Korea. According to this plan, WADGPS research group in Seoul National University (SNU) GNSS Lab. has conducted a preliminary study for implementing WADGPS for 3 years (2002 to 2004), and has developed a Korean WADGPS test bed (KWTB) (Doyoon and Changdon 2003). In this research, we secured core technology of a WADGPS. Furthermore we verified the feasibility of Korean WADGPS implementation using Korean NDGPS infrastructure. Recently Korean government has resumed the project and planned to implement Pseudolite-based WADGPS for demonstrating the feasibility of Korean WADGPS. The main goal of this project is to show the capability of Korean WADGPS using the pseudolite and existing NDGPS infrastructures in real-time. This project is scheduled for 2010 to 2014 under the contract with the Ministry of Land, Transport and Maritime affairs (MLTM). After that, Korea will launch a geostationary multifunctional satellite with a navigation payload which will be broadcasting augmenting signals for GPS. In this paper, the research results about WADGPS algorithm which have been developed up to now and the project milestones will be described. And Korean pseudolite-based WADGPS architecture and deployed infrastructures will be introduced. To show the initial performance of the system, a simulation using NDGPS RINEX data has been conducted. In this paper, we presented current states of Korean WADGPS development project and also presented conceptual design, detailed algorithms and some considerations of the system. By simulating with real data, the system performance is expected to satisfy the Wide Area Augmentation System Initial Operation Capability (WAAS IOC) requirement. After this project, ground system will be secured so that it can be used for developing Korean satellite-based WADGPS. And pseudolite broadcasting system can be used for solving a GEO visibility problem like European Geostationary Navigation Overlay Service (EGNOS) pseudolite system (Ruizhi Chen 2007).

Keyword : WADGPS, DGPS, Differential GNSS