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Eloran Initial Operational Capability in the United Kingdom – First Results

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Eloran Initial Operational Capability in the United Kingdom – First Results eLoran Initial Operational Capability in the United Kingdom – First results Gerard Offermans, Erik Johannessen, Stephen Bartlett, Charles Schue, Andrei Grebnev, UrsaNav, Inc. Martin Bransby, Paul Williams, Chris Hargreaves, General Lighthouse Authorities of the UK and Ireland BIOGRAPHIES for Loran and has authored several papers on the subject. Dr. Gerard Offermans is Senior Research Scientist of the Martin Bransby is the Manager of the Research and UrsaNav LFBU engaged in various R&D project work Radionavigation Directorate of the General Lighthouse and product development. He supports customers and Authorities of the UK and Ireland. He is responsible for operations in the European, Middle East, and Africa the delivery of its project portfolio in research and (EMEA) region from UrsaNav’s office in Belgium. Dr. development in such technical areas as AIS, eLoran, e- Offermans is one of the co-developers of the Eurofix data Navigation, GNSS and Lights. He is a Fellow of the Royal channel concept deployed at Loran installations Institute of Navigation, and holds memberships of the worldwide. Dr. Offermans received his PhD, with honors, Institute of Engineering & Technology and the US and Master’s Degree in Electrical Engineering from the Institute of Navigation. He is also a member of the Delft University of Technology. International Marine Aids to Navigation and Lighthouse Authorities’ (IALA) Aids to Navigation Management Erik Johannessen is Vice President of LF Business Committee. Development at UrsaNav. He is responsible for leading the Low Frequency Business Unit (LFBU) in business Dr. Paul Williams is a Principal Development Engineer development, and also provides technical and with the Research and Radionavigation Directorate of The operational expertise with LF Business Unit systems, General Lighthouse Authorities of the UK and Ireland, services, and products. based at Trinity House in Harwich, England. He is currently the technical lead of the GLA’s eLoran Work Steve Bartlett is Vice President of Operations for the Programme. The work involves planning the GLA’s UrsaNav LFBU. He is responsible for all aspects of maritime eLoran trials and work on a wide range of business operations including manufacturing, engineering, eLoran related projects. He holds BSc and PhD degrees in quality control, program management, and project Electronic Engineering from the University of Wales, is a delivery. Steve served as an active duty officer in the U.S. Chartered Engineer, a Fellow of the Royal Institute of Coast Guard and retired from the U.S. Coast Guard Navigation, and is chairman of the Radio Technical Reserve. He earned his BS in Electrical Engineering from Commission for Maritime Services Special Committee Northeastern University and an MS in Electrical 127 on Standards for Enhanced Loran (eLoran) Systems. Engineering from North Carolina State University. Chris Hargreaves is a Research and Development Charles Schue is co-owner and President of UrsaNav, Inc. Engineer with the Research and Radionavigation He champions providing Low Frequency Alternative Directorate of The General Lighthouse Authorities of the Positioning, Navigation, Time and Frequency, and Data UK and Ireland, based at Trinity House in Harwich, solutions for “sky-challenged” users. He served in the England. His work is focused on the GLA’s eLoran U.S. Coast Guard, where his expertise included radio project in particular measurement trials, software navigation systems, and was the first Commanding development and data analysis. He holds an MSci degree Officer of the Coast Guard’s Loran Support Unit. He in Mathematics and Physics from the University of holds Masters Degrees in Electrical Engineering, Durham, and an MSc in Navigation Technology at the Engineering Management, and Business Administration. University of Nottingham and is a member of the Institute He is a Fellow of the Royal Institute of Navigation. of Navigation and the Royal Institute of Navigation. Andrei Grebnev is Principal Engineer at UrsaNav, Inc. ABSTRACT and is responsible for the design of new products for LF systems and eLoran user equipment technology. He There is an increasing awareness in the Maritime world received BS and MS degrees in Radioelectronics that no single system can provide Position, Navigation, Engineering from Moscow Aviation Institute. He worked and Time (PNT) resiliently under all circumstances. At at the same Institute as Senior Research Engineer and this moment GPS (with augmentations) is used on most later as Chief of Receivers Laboratory. Mr. Grebnev holds commercial vessels, and in many cases integrated into patents pertaining to the use of magnetic loop antennas systems we did not expect would need or use GPS derived position or time. Even though the introduction of Glonass, forms, from the more traditional lighthouse to radio Galileo, Beidou and other GNSS systems will provide navigation systems, including the use of new Global some resilience, the underlying (satellite) technology Navigation Satellite Systems (GNSS) when they become remains the same, only providing relatively weak signals available. from space at mostly the same frequencies for compatibility and inter-operability. It is recognised that GPS, or more generally GNSS have become the primary means of obtaining Position, The International Maritime Organization (IMO) Navigation and Timing (PNT) information at sea, and recognizes the need for multiple PNT systems on board. there is no doubt that GNSS will form the primary source The organization developed the e-Navigation concept to of PNT for e-Navigation. increase maritime safety and security via means of electronic navigation, which calls for (at least) two An aim of the International Maritime Organisation (IMO) independent dissimilar sources of positioning and time in is to develop a strategic vision for e-Navigation, a navigation system to make it robust and fail safe. As a integrating existing and new navigational tools in an all- follow on, IMO’s Navigation, Communications and embracing system, contributing to enhanced navigational Search and Rescue Committee (NSCR) is considering safety and environmental protection, while reducing the Performance Standards for Multi-System Shipborne burden on the navigator. One of IMO’s requirements for Navigation Receivers, which includes placeholders for e-Navigation is that it should be resilient - robust, reliable satellite, augmentation and terrestrial systems. and dependable [1]. Requirements for redundancy, say the IMO, particularly in relation to position fixing systems, The most viable terrestrial system providing PNT services should be considered. that meet IMO’s requirements is eLoran. With three eLoran transmitters in good geometry, eLoran can provide But GPS is vulnerable to intentional and unintentional sub-10 meter (95%) horizontal positioning accuracy and interference [2, 3], while at the same time it is used in UTC synchronization within 50 ns, sufficient to be the co- many ship’s systems. Its output is displayed on the primary PNT solution next to GNSS. The General ECDIS; is transmitted to other vessels using AIS; is used Lighthouse Authorities of the United Kingdom and to calibrate the gyro compass; in the RADAR; connected Ireland (GLA) have installed Differential eLoran to the digital selective calling (DSC), its reported position Reference Stations to provide the world’s first Initial transmitted at the push of the emergency button for search Operational Capability (IOC) eLoran system. Together and rescue; the vessel data recorder; the dynamic with Loran transmitters in England, France, Germany and positioning system; surveying equipment; the ship’s Denmark, the Differential eLoran Reference Stations entertainment system for aiming the satellite dish and it provide better than 10 meter positioning accuracy at seven even synchronises the ship’s clocks! ports and port approaches along the English and Scottish East Coast. Initial Operational Capability was declared by In 2010 the GLA followed the UK Treasury methods to the end of October 2014 with Full Operational Capability produce the GLA’s eLoran Business Case [4, 5]. This planned for 2018. Other nations have begun similar comprehensive document presented and analysed various projects. options for providing ‘Resilient PNT’ in UK and Irish waters. It was clear that if the GLA chose to implement The paper describes the IOC eLoran system in the UK, eLoran it could rationalise its physical AtoN consisting of Differential eLoran RSIMs covering seven infrastructure, removing some lights and other physical major ports in England and Scotland. ASF maps for the aids, and on balance actually reduce costs by port and harbor approaches are published by the GLAs for implementing eLoran. Indeed, compared to other possible integration into maritime user equipment. The paper resilient PNT options such as GNSS hardening, radar provides initial static (zero-baseline) and dynamic absolute positioning, increasing physical AtoN provision, measurement results at the harbor and harbor approach eLoran would save the GLA millions of pounds over a areas. nominal system lifespan of 10 years from the introduction of e-Navigation services in 2018 to 2028. INTRODUCTION So, the GLA opted to provide differential Loran services The General Lighthouse Authorities of the United in selected ports on the East coast of the UK, in what they Kingdom and Ireland (GLA) comprise Trinity House, The elected to call its Initial Operational Capability (IOC). Commissioners of Irish
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