Vulnerability to the interference of GPS (Global Positioning Systems) is one of the main obstacles to performing safe marine navigation. As eLoran (Enhanced Long Range Navigation), considered as the backup navigation system of GPS, has been developed specifically in several countries, the need for GPS / eLoran integrated navigation has emerged. This study represents the integrated algorithm for GPS and eLoran to overcome the vulnerability of GPS. The main research contents are as follows: a) Formula for integrated positioning of GPS / eLoran based on range domain is suggested. b) Essential ASF (Additional Secondary Factor) estimation filter to implement positioning by eLoran is presented in terms of real-time processing instead of employing ASF grid map, which should be pre-made at a local area and be distributed to marine users. c) Procedures for determining HPL (Horizontal Protection Level) are represented so that the reliability of the integrated navigation can be investigated. d) The marine test results are presented to validate the suggested methods based on the Loran-C signal. Test results show the integrated GPS and eLoran by the suggested methods can complement each other in terms of accuracy and reliability.

中文翻译：

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使用基于距离域的增强测量方程的用于海洋应用的 GPS 和 eLoran 集成导航

GPS（全球定位系统）干扰的脆弱性是执行安全海上导航的主要障碍之一。由于eLoran（Enhanced Long Range Navigation）作为GPS的后备导航系统，在多个国家得到了专门的开发，对GPS/eLoran组合导航的需求也应运而生。这项研究代表了 GPS 和 eLoran 的集成算法，以克服 GPS 的脆弱性。主要研究内容如下： a)提出了基于距离域的GPS/eLoran综合定位公式。b) eLoran 实现定位的基本 ASF（附加次要因子）估计滤波器以实时处理的方式呈现，而不是采用 ASF 网格图，后者应在局部区域预先制作并分发给海洋用户。c) 表示确定 HPL（水平保护等级）的程序，以便可以调查组合导航的可靠性。d) 提供海上测试结果以验证基于 Loran-C 信号的建议方法。测试结果表明，集成GPS和eLoran通过建议的方法可以在准确性和可靠性方面相互补充。