Paper
Preliminary Analysis of LEX Message PPP Correction Data and a Novel Approach to Improve the Accuracy of LEX Message Data
- Authors:
- L. Samarakoon; T Tipdecho; M Parnichkun; C. H Wickramasinghe
- Abstract
- Quasi-Zenith Satellite System (QZSS) is a Japanese GPS augmentation system that provides real-time Precise Point Positioning (PPP) correction through an experimental signal (LEX) established in June 2011. LEX signal provides real-time GPS satellite ephemeris and clock correction. The accuracy of these corrections directly affects the positioning accuracy. This paper compares the LEX PPP data with the IGS Ultra rapid data products to analyze the accuracy of LEX data. The analysis showed that LEX data has systematic errors that can be corrected. A new algorithm was developed to correct clock error and ephemeris errors using a liner model and wavelet transformation. This method improved LEX ephemeris accuracy to decimeter level and the clock correction accuracy to 0.01 microseconds. As a result, LEX based real-time positioning accuracy was improved by 37%.
- Keywords
- GPS; PPP; QZSS; LEX
- StartPage
- 15
- EndPage
- 24
- Doi