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http://dx.doi.org/10.5394/KINPR.2012.36.6.475

Measurement of Reference Phase Offset for the Loran-C Transmitting Signal of Pohang  

Lee, Chang-Bok (Korea Research Institute of Standards and Science)
Won, Sung-Ho (Korea Research Institute of Standards and Science)
Lee, Jong-Koo (Korea Research Institute of Standards and Science)
Kim, Young-Jae (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.36, no.6, 2012 , pp. 475-480 More about this Journal
Abstract
In order to establish eLoran (enhanced Long Range Navigation) system, it needs the advancement of receiver, transmitter, data channel addition for Loran information, differential Loran sites for compensating Loran-c signal and ASFs (Additional Secondary Factors) database, etc. In addition, the precise synchronization of transmitting station to the UTC (Coordinated Universal Time) is essential if Loran delivers the high absolute accuracy of navigation demanded for maritime harbor entrance. For better timing synchronization to the UTC among transmitting stations, it is necessary to measure and monitor the transmission delay of the station, and the correction information of the transmitting station should be provided to the user's receivers. In this paper we presented the measurement method of absolute delay of Pohang Loran transmitting station and developed a time delay measurement system and a phase monitoring system for Loran station. We achieved -2.23 us as a result of the absolute phase delay of Pohang station and the drift of Loran pulse of the station was measured about 0.3 us for a month period. Therefore it is necessary to measure the delay offset of transmitting station and to compensate the drift of the Loran signal for the high accuracy application of PNT (Positioning, Navigation and Timing).
Keywords
Loran; UTC; TOA; TOC; (A)SF; phase offset; time synchronization; eLoran;
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