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http://dx.doi.org/10.5394/KINPR.2010.34.3.175

Comparison of Predicted and Measured ASF  

Shin, Mi-Young (Department of Electronics Engineering, Chungnam National University, Korea)
Hwang, Sang-Wook (Department of Electronics Engineering, Chungnam National University, Korea)
Yu, Dong-Hui (Department of Multimedia Engineering, Catholic University of Pusan, Korea)
Park, Chan-Sik (Department of Electronics Engineering, Chungbuk National University, Korea)
Lee, Chang-Bok (Time and Frequency Group, Korea Research Institute of Standard and Science, Korea)
Lee, Sang-Jeong (Department of Electronics Engineering, Chungnam National University, Korea)
Publication Information
Journal of Navigation and Port Research / v.34, no.3, 2010 , pp. 175-180 More about this Journal
Abstract
In the almost application parts, GNSS being used the primary navigation system on world-widely. However, some of nations attempt or deliberate to enhance current Loran system, as a backup to satellite navigation system because of the vulnerability to the disturbance signal. Loran interests in supplemental navigation system by the development and enhancement, which is called eLoran, and that consists of advancement of receiver and transmitter and of differential Loran in order to increase the accuracy of current Loran-C. A significant factor limiting the ranging accuracy of the eLoran signal is the ASF in the TOAs observed by the receiver. The ASF is mostly due to the fact that the ground-wave signal is likely to propagate over paths of varying conductivity and topography. This paper presents comparison results between the predicted ASF and the measured ASF in a southern east region of Korea. For predicting ASF, the Monteath model is used. Actual ASF is measured from the legacy Loran signal transmitted Pohang station in the GRI 9930 chain. The test results showed the repeatability of the measured ASF and the consistent characteristics between the predicted and the measured ASF values.
Keywords
eLoran; Propagation delay error; ASF; Predicted ASF; Measured ASF; Temporal ASF; Spatial ASF;
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