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Old 26 August 2007, 12:56   #1
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GPS/LoranC/?

What started out as a compass discussion in "Ribs and Ribing" turned into a GPS discussion related to reliability. I have discovered the following facts.

Uptime:
GPS up time 99.66%
Loran C up time 99.99%

Vulnerability:
GPS - Easy to construct jammer for less than $100 to jam for 120 nm radius
Loran C - Difficult if to jam but easy to bomb transmitter site

Politics:
US - Were ready to abandon Loran-C but now not so sure. Comments from Department of Transportation requested in January of 07 to decommission, maintain status quo or upgrade. Current support runs out in 2015. Point made that Loran C given life support primarily to provide redundancy on aircraft.
EU - In process of upgrading with technology that adds GPS corrections to Loran C radio signal. US "donated" Loran C stations to EU after they got GPS up and running. EU keeps tossing about launching "their own" satellite array to provide an alternative to GPS. EU tried to get US control of GPS system out of US Military and into more universal control. Russia half funded a sloppy alternative to GPS but it ain't accurate.

Receivers:

Much talk about the combination Loran-C/GPS receivers. As much talk about NO manufacturer wanting to put the money in to such units if Loran C's future is not guaranteed. I searched for both combo units and plain old Loran C receivers and Googled a Blank!

Are there any electronic navigation freaks out there with opinions or facts related to all of the above. I still maintain that for recreational boating purposes a quality GPS Chart Plotter is the best thing since sliced bread. Yes, I own a compass and yes I have studied both pilotage and navigation and a further yes, I agree that GPS is "down" .34% of the time so don't launch on me on these issues, pls

I admit that I didn't even have a clue that Loran C was still operable in North America. My first electronic nav. instrument was a Micrologic that displayed only Time Differentials! I'd be tickled if someone could even provide me a link to where I would purchase a Loran unit, in the US or Europe, just out of curiosity.
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Old 26 August 2007, 17:55   #2
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I fully agree GPS is awesome. BUT if it had packed up for any reason when I was bringing my boat back from Guernsey i would have been buggered. The compass that should have been fitted wasn't so all I had was a handbearing model. I had no charts either.

I DID have a handheld gps but if some stupid schoolboy had decided to muck about I would have been in trouble.

A backup would be great. Especially one of the older systems. Yes transmitters can be bombed but I suspect that accidental or malicious jamming is far more likely.

It's a shame they have decided to keep on with LORAN - DECCA would have been much better. Rolling map displays in the 1950s!!!

http://en.wikipedia.org/wiki/Decca_Navigator_System

DECCA is a classic example of how the Yanks hate anything not made in the USA!!!

"The Decca installations in the New York Airways helicopters included the unique Decca 'roller map' displays that enabled the pilot to see his or her position at a glance, a concept unfeasible with VOR/DME. This chain installation was considered highly controversial at the time, for political reasons. This led to the U.S. Coast Guard, under instructions from the Treasury Department to which it reported, banning the use of Decca receivers in ships entering New York harbor for fear that the system might create a de facto standard (as it had become in other areas of the world)."
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Old 26 August 2007, 21:46   #3
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Quote:
Originally Posted by codprawn View Post
I DID have a handheld gps but if some stupid schoolboy had decided to muck about I would have been in trouble.

And...I could get hit by lightening while picking coconuts!


It's a shame they have decided to keep on with LORAN - DECCA would have been much better. Rolling map displays in the 1950s!!!

And...coulda been shoulda been ain't what I'm asking.

DECCA is a classic example of how the Yanks hate anything not made in the USA!!!

Nothing is made in USA anymore; it's all from China

"
"No intention to shout at you Codder, use of bold was to separate my replies to some of your points. Your post is appreciated...let's get to the bottom of this since we (or at least I am) isolated on a remote island and my dog refuses to discuss anyting more stimulating than what time of day he gets fed"

Let's rephrase this as a challenge:

If EU is refurbishing their inherited Loran C system, where do I purchase a Loran C Receiver. Forget Ribs, let's say I operate an ocean going tug just to make the solution easier. What benefit is there to Loran C in the world we inhabit? If we're talking reliability to the ultimate degree, when are we going to see $800 submersable chart plotting Loran C/GPS combo receivers?

Any takers?

This is not an attempt to make EU look silly. The United States Department of Transportation, in concert with the Department of Homeland Security, is currently debating whether to ditch or upgrade Loran C in North America. OK, If I'm Virgin Airline and have only GPS to steer me to Vector points in Canada and Scotland after crossing the Atlantic Ocean I might find Loran backup useful. Is that reason enough for Loran C to continue? Are you, the consumer getting your money's worth from enhancement of Loran C in Europe or given the huge expenditure, by creating your own GPS duplication?

"And finally the super-power aspirations of the European Union resulted in a political pressure to not be reliant in the US defense for navigation signals. EU tried to persuade the USA to put GPS under civilian or NATO control. When that failed, a project "Galileo" was launched, which should put Europes own GPS system aloft.

...except, the EU was not prepared to foot the bill, so some vague dot-com like calculations shows how it will be a great benefit to "the industry" and that they therefore will be more than willing to pay. The industry seems unaware of this, and Galileo struggles from one budget to the next, only funded enough to be a sufficient credible threat in the negotiations with the USAnians, who on the other hand tries every means available to them to kill it dead in the crib.

In the meantime, a bunch of dutch boffins have come up with a way to use the incredibly resillient LORAN-C signals as a channel for transmitting dGPS signals, and managed to secure enough funds to get this implemented on most of the NELS transmitters under the US-fobic name of EuroFix.

So where does that leave LORAN-C for the future ?

The main concern today is the fact that the GPS signals are so easy to jam, either by the US military or by means of a home-built gadget which most high-school proto engineers could build in their room without their parents knowing about it.

The fact that Galileo is designed to use the same center frequency as GPS and therefore would be jammed along with GPS, is hopefully something which in the end will prevent the EU from wasting more tax-payer money than absolutely necessary on the project. (NB: You won't find my money in a bet on that.)

LORAN-C signals on the other hand goes through everything and can only be plausibly denied if you use explosives on the remotely located transmitters.

It would therefore seem to any rational mind that LORAN-C makes the perfect backup for GPS, and that integrated GPS+LORAN-C receivers would be the next great thing: LORAN-C would provide coverage where GPS can't and GPS would allow one to calibrate the LORAN-C signal to build the necessary correction database to use LORAN-C for normal navigation purposes.

Add to this that for the cost of one launch of a single Galileo satelite, you can add a couple of LORAN-C stations, and run them all for as long as the satelite would last, and that you need 20-30 satelites for the entire Galileo system and the math works out too.

So why isn't this happening ?

NELS currently promises LORAN-C signals until 2005 or possibly 2008, either way, no sane executive is going to bet corporate money on developing an integrated GPS+LORAN-C receiver only to arrive on the market when the signals disappear. With no receivers on the market, NELS has a hard time arguing for wasting public money transmitting signals nobody listens to. Catch-22.
"

This article is dated, circa 2003 however....currently NELS, the upgraded Loran C stations in Europe are reality and I am not aware of any kill date for the Euro system although the North American system still carries a 2015 kill date.

Snotty essay if I do say so myself but the points are what the points are even when separated from the EU/USA blather. I personally don't disagree though with EU concerns over having the Pentagon own the primary worldwide system of navigation. Donald Rumsfeld is gone but I keep getting this bad picture in my head of him at the on/off switch

Post Script:

One amazing fact I discovered is that new Loran Transmitters that have been installed at some locations in the US and Canada utilize transmission "towers" that are only two inches tall. Damn!

Politicians and "Security Freaks" come up with all kind of ways to spend your money. The market rules however and if there is widespread value to Loran C, where is the market in terms of providing receivers to the public?
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Old 27 August 2007, 11:24   #4
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Comments on eLoran and Receiver Sources

Before I launch into my post I need to make a couple of disclaimers up front. I am currently the CEO of CrossRate Technology which is a company that is developing and selling integrated GPS/eLoran receivers. Prior to running this company I was in the Coast Guard and my last duty station was as the Configuration Manager for the North American Loran System.

It appears to me that there are two basic questions being asked in this thread.

1) Why are we even discussing the continuation of Loran when GPS rocks?
2) If an integrated receiver is such a good idea then where can I buy one?

Answer to question 1.

A brief recap of the recent history of the Loran-C system.

In the 1990s the system was scheduled to be shut down in 2000. In the late 90s some people crawled out of the woodwork and said, are you sure you want to do that? A moment of pause occurred and a GPS Vulnerability Study was undertaken by the Volpe Transportation Center. The result of the study is that GPS is vulnerable and that the government should provide a backup system.

Following this report a slew of studies were undertaken by groups that included the government, academic and industry representatives to determine if Loran could provide a backup to GPS. The two primary studies were the Loran Accuracy Performance Panel and the Loran Integrity Performance Panel. These two studies determined that Loran, if upgraded to eLoran, can act as a backup to GPS.

Most recently the Department of Transportation commissioned the Loran Independent Assessment Team to compile the decades of research and make a recommendation to the Secretary. Dr. Brad Parkinson, the father of GPS, was brought into chair the panel. The panel itself was made up of GPS all stars with no link back to the Loran system. The unanimous recommendation from this panel was the long term operation of eLoran as the backup to GPS.

It is also important to broaden the user base discussion. GPS is used to provide precise time to many systems including the power delivery system, phone systems, T.V. systems, the internet, 911 communications, Nasdaq, ATM machines, and more. The reason I bring this up is because we are talking about a critical national infrastructure decision that has broad implications across several user groups.

The bottom line is that GPS position and time information is critical to many safety of life applications and is embedded throughout our economy. A disruption to that information, whether intentional or unintentional, could have a significant impact. Because of this it is imperative for the government to protect itself by providing a backup system. eLoran is by far the best system to backup GPS. In repeated studies it has been shown to not only meet the technical requirements, but has also been shown to be cost effective.

In terms of dollars we are talking about a system that costs the U.S. approximately $30M a year to run. This works out to Roughly a dime per person. If the government were to embrace all of the cost cutting technology and remotely operate the stations the cost would to somewhere between $10M and $15M annually. Compare this cost to the ~$700M that it costs to run GPS annually.

If you are interested in the issue there are a couple of sites you might like to check out.

www.loran.org
www.crossrate.com (go to the news and resources section and you can find background info.)

Question 2

CrossRate integrated GPS/eLoran receivers should be on the market in January 2008.
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Old 27 August 2007, 13:49   #5
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Quote:
Originally Posted by CrossRate View Post
It appears to me that there are two basic questions being asked in this thread.

1) Why are we even discussing the continuation of Loran when GPS rocks?
2) If an integrated receiver is such a good idea then where can I buy one?


CrossRate integrated GPS/eLoran receivers should be on the market in January 2008.
Thank you for your reply. Yes, the two questions you deduced from my ramble were the two questions that begged asking. The information you offer greatly increases my knowlege of the current value of Loran. I was not aware of the value to such a broad spectrum of users, other than those looking for x/y position.

I linked to your company's web site and reviewed the information there. The explosive growth in various gps driven chart plotters has resulted in pricing that allows even "casual" users to afford the technology. Casual is a term that must be used carefully as it applied to any marine application. We are not talking an inability to locate the nearest Pizza Joint but for even the recreational boater, potential life or death assistance at critical moments.

They call me "Doubting Tomas" and part of my point was that if application of Loran or eLoran to Gps was a worthy expenditure of government funds, it should follow that receivers capable of utilizing the technology should be finding their way to the market place. I look forward to reviews of your product, once it has been released and.....look forward to learning what price this trick will set one back!

Thank you for the information.

Message to the forum: Will eNavigation be any closer to Bullet Proof when we all have a CrossRate receiver? I admit that my comment in Ribs & Ribbing describing GPS as bulletproof does not stand up as well to the reality of the situation, as I would have imagined. Yes, I'll still have the damn compass at least for the next 1,200 years until the Earth's magnetic field fails!

Oh, by the way....as far as I know Loran has not and will not do me a darn bit of good because of my remote location. You buggers on the North American continent and Europe get all the good stuff
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