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http://dx.doi.org/10.5394/KINPR.2013.37.4.375

A generation method of ASF mapping by the predicted ASF with the measured one in the Yeongil Bay  

Hwang, Sang-Wook (Department of Electronics Engineering, Chungnam National University)
Shin, Mi Young (Maritime Safety Research Division, Korea Institute of Ocean Science & Technology)
Choi, Yun Sub (Department of Electronics Engineering, Chungnam National University)
Yu, Donghui (Department of Multimedia Engineering, Catholic University of Pusan)
Park, Chansik (Department of Electronics Engineering, Chungbuk National University)
Yang, Sung-Hoon (Time and Frequency Group, Korea Research Institute of Standard and Science)
Lee, Chang-Bok (Time and Frequency Group, Korea Research Institute of Standard and Science)
Lee, Sang Jeong (Department of Electronics Engineering, Chungnam National University)
Publication Information
Journal of Navigation and Port Research / v.37, no.4, 2013 , pp. 375-381 More about this Journal
Abstract
In order to establish eLoran system it needs the betterment of a receiver and a transmitter, the add of data channel to loran pulse for loran system information and the differential Loran for compensating Loran-c signal. Precise ASF database map is essential if the Loran delivers the high absolute accuracy of navigation demanded at maritime harbor entrance. In this study we developed the ASF mapping method using predicted ASFs compensated by the measured ASFs for maritime in the harbor. Actual ASF is measured by the legacy Loran signal transmitted from Pohang station in the GRI 9930 chain. We measured absolute propagation delay between the Pohang transmitting station and the measurement points by comparing with the cesium clock for the calculation of the ASFs. Monteath model was used for the irregular terrain along the propagation path in the Yeongil Bay. We measured the actual ASFs at the 12 measurement points over the Yeongil Bay. In our ASF-mapping method we estimated that the each offsets between the predicted and the measured ASFs at the 12 spaced points in the Yeongil. We obtained the ASF map by adjusting the predicted ASF results to fit the measured ASFs over Yeungil bay.
Keywords
eLoran; HEA; ASF map; propagation delay; monteath model;
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