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http://dx.doi.org/10.5394/KINPR.2016.40.6.385

A Time Comparison Measurement Technique for eLoran Receivers  

Lee, Chang-Bok (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)
Hwang, Sang-wook (Korea Research Institute of Standards and Science)
Yang, Sung-Hoon (Korea Research Institute of Standards and Science)
Publication Information
Journal of Navigation and Port Research / v.40, no.6, 2016 , pp. 385-390 More about this Journal
Abstract
ELoran Systems can provide Position, Navigation, and Time services with comparable performance to Global Positioning Systems (GPS) as a back up or alternative system. High timing and navigation performance can be achieved by eLoran signals because eLoran receivers use "all-in-view" reception. This incorporates Time of Arrival (TOA) signals from all stations in the service range because each eLoran station is synchronized to Coordinated Universal Time (UTC). Transmission station information and the differential Loran correction data are transmitted via an additional Loran Data Channel (LDC) on the transmitted eLoran signal such that eLoran provides improved Position Navigation and Timing (PNT) over legacy Loran. In this paper, we propose a technique for adapting the delay time compensation values in eLoran timing receivers to provide precise time comparison. For this purpose, we have designed a system that measures time delay from the crossing point of the third cycle extracted from the current transformer at the end point of the transmitter. The receiver delay was measured by connecting an active H-field, an E-field and a passive loop antenna to a commercial eLoran timing receiver. The common-view time transfer technique using the calibrated eLoran timing receiver improved the eLoran transfer time. A eLoran timing receiver calibrated by this method can be utilized in the field for precise time comparison as a GNSS backup.
Keywords
ELoran; Timing Recevier; UTC; Receiver Delay; Common-View Time Transfer;
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