A Long-term Accuracy Analysis of the GPS Klobuchar Ionosphere Model

GPS Klobuchar 전리층 모델의 장기간 정확도 분석

Kim, Mingyu;Kim, Jeongrae

  • Received : 2016.05.01
  • Accepted : 2016.06.20
  • Published : 2016.06.30


Global Positioning System (GPS) is currently widely used for aviation applications. Single-frequency GPS receivers are highly affected by the ionospheric delay error, and the ionospheric delay should be corrected for accurate positioning. Single-frequency GPS receivers use the Klobuchar model, whose model parameters are transmitted from GPS satellites. In this paper, the long-term accuracy of the Klobuchar model from 2002 to 2014 is analyzed. The IGS global ionosphere map is considered as true ionospheric delay, and hourly, seasonal, and geographical error variations are analyzed. Histogram of the ionospheric delay error is also analyzed. The influence of solar and geomagnetic activity on the Klobuchar model error is analyzed, and the Klobuchar model error is highly correlated with solar activity. The results show that the Klobuchar model estimates 8 total electron content unit (TECU) over the true ionosphere delay in average. The Klobuchar model error is greater than 12 TECU within $20^{\circ}$ latitude, and the error is less than 6 TECU at high latitude.


Global Positioning System (GPS);Global Navigation Satellite System;Klobuchar model;Ionospheric delay


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Supported by : 국방과학연구소