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http://dx.doi.org/10.5394/KINPR.2015.40.1.15

Improvement of Loran-C Timing Accuracy by Inland Differential ASF Measurements  

Lee, Chang-Bok (Korea Research Institute of Standards and Science)
Hwang, Sang-Wook (Korea Research Institute of Standards and Science)
Lee, Jong-Koo (Korea Research Institute of Standards and Science)
Lee, Young-Kyu (Korea Research Institute of Standards and Science)
Lee, Sang-Jeong (Chungnam National University)
Yang, Sung-hoon (Korea Research Institute of Standards and Science)
Publication Information
Journal of Navigation and Port Research / v.40, no.1, 2016 , pp. 15-20 More about this Journal
Abstract
In this study we measured a differential ASF to improve the accuracy of time synchronization with the signal transmitted from Pohang 9930M Loran station. We obtained the differential ASF which is calculated from a difference of the TOA measurements between KRISS and Chungnam National University(CNU), and KRISS and National Maritime PNT Office respectively. The TOA measurement at KRISS was measured by UTC(KRIS) reference clock and other sites were measured by atomic clocks respectively. The time variations of differential ASF measurements at CNU and National Maritime PNT Office were within $0.1{\mu}s$ and $0.05{\mu}s$ respectively. And we found the time variations of $0.1{\mu}s$ depending on the surrounding radio-wave environments from the differential ASF measurements of 60 minute moving averages. We can improve the accuracy of time synchronization of the local clock to within 10 ns by compensating the differential ASF through removing the common component of ASF. And we measured the absolute ASF between the Pohang transmit station and KRISS by the measurement technique of absolute time delay using a cesium atomic clock. The average ASF between two points is about $3.5{\mu}s$.
Keywords
Loran; differential ASF; TOA measurements; timing accuracy; propagation delay;
Citations & Related Records
Times Cited By KSCI : 2  (Citation Analysis)
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