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eDLoran Surprise: European Navigation Conference 2014

May 14, 2014  - By

At the ENC-GNSS Conference in Rotterdam, we delved into actions necessary to officially use EGNOS (giving me déjà vu from WAAS’s early days), heard sage words from Brad Parkinson, the father of GPS, and, on the last day, saw amazing proof of a claim many of us initially thought was outrageous — that differential (DLoran) with modern monitoring can result in consistent horizontal accuracies approaching five meters on a moving platform.

When I was asked if I could cover the European Navigation Conference 2014 (ENC-GNSS) in Rotterdam, The Netherlands, it took me about two seconds to answer in the affirmative. Let’s see… Travel to Europe in the spring, visit The Netherlands — my old stomping grounds where my daughter was born — see miles and miles of beautiful Tulips in bloom, and visit with some old friends. Gee, what a tough decision. Oh, and of course, cover the ENC. Almost forgot that

Seriously, my primary purpose, of course, was to cover the ENC and associated events such as the Resilient PNT Forum and a meeting of the European Maritime Radionavigation Forum (EMRF), but literally miles and miles of brilliant red, white, and yellow tulips interspersed with ancient windmills are hard to ignore. But I digress.

In past years the ENC, with approximately 400 attendees, has been naturally dedicated to European PNT matters, and in reality it concentrated almost exclusively on Galileo with a slight mention of EGNOS. That was about it. This year, the venue was the same, but the program was more open, with presentations on PNT augmentations such as EGNOS and DLoran, and maritime navigation to include radar and inertial systems.

For those of us that have been in the PNT (positioning, navigation and timing) or merely the navigation business, say, for the past 40+ years or so, in some respects it was more than slightly reminiscent of times past. As the great American octogenarian baseball philosopher and malapropism aficionado extraordinaire, Yogi Berra, once said, “It was déjà vu all over again.”

European Maritime Radionavigation Forum

The Port of Rotterdam today (2014).

The Port of Rotterdam today (2014).

The EMRF was the first official function to kick off in Rotterdam. When you consider that Rotterdam is one of the busiest ports in Europe and had been around since 1340, you would naturally expect one of the main conversations at the EMRF to concern the port of Rotterdam and navigating in less-than-perfect conditions. The Netherlands is known as the Low Country, and that is as an apt description since most of the country is below sea level — hence the persistent fog, dikes, sea walls, and windmills that pump water and grind grain and all those good things. Today, the modern versions of those windmills are huge — twenty stories tall — and generate electricity. Many of them are close to shore so precise navigation in foggy conditions is even more critical than in times past.

The main topic of conversation at the EMRF revolved around the actions necessary to officially use EGNOS (the European Geostationary Navigation Overlay Service) as a precision and official safety-of-life augmentation for GPS (similar to WAAS, Wide Area Augmentation System) and Galileo.

During those discussions, I swear when I closed my eyes, except for the accented English, I was propelled backward almost 20 years to discussions of WAAS as a safety-of-life system, not for maritime but for aviation purposes. Still, the dialogue and heated discussions echoed down through the years almost verbatim. The main difference, of course, being that in the U.S. it was 20 years earlier, we were embarking on virgin territory, and we had only ourselves, one nation, to debate. Whereas the Europeans are fighting the same battles two decades later, with a system that is purposefully almost an identical copy of WAAS technically, and they are working for maritime and aviation certifications simultaneously. And not with just one nation but the entire European Union. A truly daunting task.

The EMRF website is sponsored by Trinity House in London, which is responsible for the safety of [English and European] shipping and the well being of seafarers, which have been their prime concerns ever since Trinity House was granted a Royal Charter by Henry VIII in 1514. I planned to list the EMRF website for your further edification, but since the latest news on the site concerns the upcoming January 2011 EMRF meeting in Paris, I thought it was best left to molder in obscurity. The website, not the EMRF.

The bottom line for the EMRF is that while it fills an important role where EGNOS and maritime navigation are concerned, it still has a lot to learn and could benefit greatly by lessons learned from WAAS. However, I personally see no indication that will happen, so we wish them luck. Many of us are standing by to assist if asked. Even if it is only, “Been there, tried that, and here is why it did or did not work.” Quod homo non sit Island.

Resilient PNT Forum

I was happy to see Dana Goward (USCG Ret), the head honcho at the Resilient Navigation and Timing Foundation, which conducted the Resilient PNT Forum at ENC 2014. Dana’s forum, which took place just before the official ENC 2014 kickoff, concentrated on the need for and strategies to achieve resilient position, navigation and timing (PNT) services. The event was well attended, and was jointly hosted by the European Group of Institutes of Navigation, the International Association of Institutes of Navigation, and the International Association of Marine Aids to Navigation and Lighthouse Authorities. There was no charge to attend the event, and the collaboration proved interesting, especially since Dana really wanted to talk eLORAN and GPS/Galileo augmentations.

Dana is retired U.S. Coast Guard and worked many years supporting LORAN-C and the USCG Navigation Center. Dana showed a brief video of his recent testimony before the U.S. Congress, where he lobbied for a cessation of the destruction of LORAN-C towers and their associated infrastructure. If recent congressional actions are any indication, he has been somewhat successful in that regard. Now all that is left is to help the U.S. Congress, services, and agencies realize how badly the United States needs LORAN as a backup, enhancement, and augmentation to GPS and other space-based PNT services on a global basis. No small task, but it is a task that Dana Goward and the Resilient Navigation and Timing Foundation have strapped on, and we wish them the best. Plus, as you will see later, a surprise presentation at ENC-GNSS may have given Dana and his cause just the boost they need. Keep reading.

As it turns out, many others thought these non-Galileo presentations were timely topics as well, and the discussions were enlightening, especially the Resilient PNT Forum keynote address by Professor David Last. Among many other titles he holds, Last is a consultant engineer and expert witness specializing in radio navigation and communications systems. He is a professor emeritus at the University of Bangor, Wales, and past president of the Royal Institute of Navigation. He acts as a consultant on radio-navigation and communications to companies and to governmental and international organizations and is active as an expert witness, especially in forensic matters concerning GPS.David and I are old friends, and it is always enlightening and entertaining to hear him speak. On this occasion, Professor Last spoke eloquently and authoritatively concerning the ubiquity of GPS/PNT and the resultant and inherent vulnerabilities of space-based systems. David made the essential point that while GPS remains the sine qua non of PNT, it is still vulnerable and subject to failures as are all space-based PNT systems, the recent GLONASS debacles being prime examples. More on these unfortunate Russian examples of PNT vulnerability at a later date.

David pressed the issue, as he has many times, that we desperately need a ground system or many different ground-based augmentations, backups, and enhancements to ensure that the user is never without navigation and timing data at a critical juncture, such as navigating through an insanely busy commercial port in thick fog.

This theme was carried forward in the ENC-GNSS very adroitly by none other than Dr. Bradford Parkinson, the Father of GPS. Dr. Parkinson spoke at length on the need to “Protect, Toughen, and Augment GNSS” against all enemies, be they manmade or natural. Brad made the point, with all due credit to Will Rogers, that “Rumors of GPS’ death are greatly exaggerated.” Indeed, the GPS constellation has never had more satellites on orbit, in residual status, and spares in the barn than we do today. The SIS or Signal In Space has never been more accurate, and the GPS atomic reference systems have never been more stable than today, and yet GPS remains incredibly vulnerable. But take heart, as Dr. Parkinson is convinced “There are actions such as PTA that can be taken to safeguard PNT for all users.” We will cover Dr. Parkinson’s 60+-slide presentation in depth at a later date.

Surprise! Loran Is the Answer

The big surprise came on the last official day of the conference during a group of alternate PNT presentations co-chaired by Dr. David Last. The rather startling enhanced differention LORAN (eDLoran) presentation was given by Professor Durk van Willigen, representing his colleagues René Kellenbach and Cees Dekker of the Dutch consulting firm Reelektronika, and Wim van Buuren of the Dutch Pilots’ [ed. maritime] Corporation, who helped with the DLoran research and authoring of the paper for the ENC presentation.

Professor van Willigen made what many of us initially thought was an outrageous claim, and then amazingly went on to prove that enhanced differential Loran with modern monitoring produced consistent horizontal accuracies approaching five meters on a moving platform. Needless to say, Professor van Willigen, who teaches at the Delft University of Technology in The Netherlands, was mobbed at the end of his presentation, but I did manage to catch him for a few minutes afterwards. Since then, GPS World Editor-in-Chief Alan Cameron has spoken with Professor van Willigen at length, and the result is the first of what I am sure will prove to be numerous articles on eDLoran in GPS World.

Shipboard DLORAN receiver installation (orange boxes on rails).

Shipboard DLoran receiver installation (orange boxes on rails).

One would hope that with this rather startling improvement in differential Loran accuracy and the decision by the U.S. Congress to halt the destruction of Loran-C infrastructure in North America, that there might once again be a future for Loran, especially eLoran and/or DLoran in North America, and hopefully globally as well.

As Professor David Last in his best imitation of John Cleese might say, “It is the answer to a maiden.s prayer.”

Until next time, happy navigating. I hope to see you all at the 30th Space Symposium May 19-22 in Colorado Springs at the Broadmoor Resort. More than 10,000 attendees are expected, and I hope you will be one of them. Stop by the GPS World booth and say hello.

 

About the Author: Don Jewell

Don Jewell served 30 years in the United States Air Force, as an aviator and a space subject-matter expert. Don’s involvement with GPS and other critical space systems began with their inception, either as a test system evaluator or user. He served two command assignments at Schriever AFB, the home of GPS, and retired as Deputy Chief Scientist for Air Force Space Command. Don also served as a Politico Military Affairs Officer during the Reagan administration, working with 32 foreign embassies and serving as a Foreign Disclosure Officer making critical export control decisions concerning sophisticated military hardware and software. After retiring from the USAF, Don served seven years as the senior space marketer and subject-matter expert for two of the largest government contractors dealing in space software and hardware. Don currently serves on two independent GPS review teams he helped found, and on three independent assessment teams at the Institute for Defense Analyses, dealing with critical issues for the U.S. government. Don has served on numerous Air Force and Defense Scientific Advisory Boards. He writes and speaks extensively on technical issues concerning the U.S. government. Don earned his Bachelor’s degree and MBA; the Ph.D. is in progress.

1 Comment on "eDLoran Surprise: European Navigation Conference 2014"

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  1. JJM says:

    Very good. Ridiculous to remove a worldwide infrastructure of positioning capabilities. Loran C worked acceptably provided it could be properly calibrated in the work area. eLoran provides a data channel in the signal which potentially could carry signal corrections. What I read, 1 of the accuracy problems is data latency of the corrections. Over 2 decades ago we struggled with similar problems delivering GPS corrections. While lower accuracies may be acceptable for open sea passage it certainly seems possible to gain high accuracy where required in harbors with local reference stations and higher speed differential transmitters. And then again, Beacon Differentials are delivered for all-in-view within reasonable time frames at near the same low frequencies.
    I assume that eLoran can be used in hyperbolic as well as range-range mode to obtain best HDOP.