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Is National Differential GPS Lost?

kdawson posted more than 7 years ago | from the so-where-are-we-again? dept.

109

Nealix writes, "This article at GPSWorld reports that National Differential GPS (NDGPS) is endangered in the 2007 budget. This has ramifications for a variety of government programs such as the Intelligent Transportation System and Positive Train Control by the Department of Transportation. Blind people and robots also benefit from highly accurate GPS navigational capability provided by NDGPS, which appears to work better in the urban canyons. If NDGPS loses, the winner would appear to be the FAA-backed Wide Area Augmentation Service (WAAS). Of course, what would be really cool is to see more GPS sites around the country make DGPS data (RTCM) available over the Internet."

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109 comments

Of Course! (5, Funny)

duerra (684053) | more than 7 years ago | (#16046737)

Ah yes, of course GPS making use of DGPS data (RTCM) would be better than FAA-backed WAAS if NDGPS loses - everybody knows that. Now, BRB while I RTFA.

Re:Of Course! (1)

Quintios (594318) | more than 7 years ago | (#16046765)

STFU

Re:Of Course! (1)

pcmanjon (735165) | more than 7 years ago | (#16046778)

What will this mean for us street atlas GPS Users?

Re:Of Course! (1)

megaditto (982598) | more than 7 years ago | (#16046805)

nothing

Re:Of Course! (1)

mikael (484) | more than 7 years ago | (#16047074)

Nothing for you to see here, please move along ....

Re:Of Course! (2, Informative)

jfengel (409917) | more than 7 years ago | (#16047102)

Your street atlas GPS probably doesn't use NDGPS. It uses plain old satellite-based GPS, and that's just fine.

Differential GPS greatly improves your precision, from meters to centimeters, but you don't really need that to give directions. You'd want it if you were actually letting the thing steer your car, but we're not there yet.

Re:Of Course! (2, Informative)

Goldenhawk (242867) | more than 7 years ago | (#16047489)

>Your street atlas GPS probably doesn't use NDGPS. It uses plain old satellite-based GPS, and that's just fine.

Welllllll...

Actually most consumer devices ALSO uses WAAS. Plain old satellite is "just fine" even without WAAS, but WAAS really helps refine the position.

Especially in the "urban canyons", normal GPS signals are pretty bad at times. Get in the city around tall buildings, and you'll see your accuracy get into the hundreds of feet if only three satellites are in view and lots of signal reflections are muddying the data. That's enough to put you a block away from your actual location. So WAAS or DGPS really helps in those situations. Sure, out in the middle of a cornfield in Kansas, you might not care about DGPS, but in that case you often have eight or ten satellites available and an accuracy of perhaps 15 feet. Not in the middle of the city.

Re:Of Course! (2, Interesting)

skroz (7870) | more than 7 years ago | (#16047855)

Sure, out in the middle of a cornfield in Kansas, you might not care about DGPS, but in that case you often have eight or ten satellites available and an accuracy of perhaps 15 feet. Not in the middle of the city.


Not true. In the middl of a cornfield in Knasas, where farm machinery is uften automated and steered via GPS, extreme precision is critical. Non only that, but your sample rate is often much higher than the .5 to 1 Hz seen in most consumer GPS units.

If your thresher (or whatever) is out in the field "threshing" you'll want to make sure that the individual rows it covers are even and as close together as possible. Too much overlap and you're wasting time and fuel. Without overlap you would miss "product."

Re:Of Course! (1)

megaditto (982598) | more than 7 years ago | (#16049903)

Wow, I never knew they had that level of automation.

By the way, do you know how the farmers still stay in business? I heard from a relative they only get about $10/acre at best. That just doesn't seem nearly enough to provide for the family, let alone buy GPS steering. Or do they also get the subsidies then?

Re:Of Course! (1)

topham (32406) | more than 7 years ago | (#16050088)


Doing a search on the Internet reveals crop guarantees at $167/acre when I did a search on Wheat. Now, I didn't very which year, etc. But I expect the document is 'current' (last five years or so).

$167/acre, with 1000 is $167,000 - costs = ?

While I don't know what farmers costs are, I saw numbers published a few years ago where the local farmers were complaining because they only made $45-55,000 Net Income.

I don't know about you, but where I live thats significantly above average net income.

You may not get rich being a farmer, but I don't think there are all that hard done by either.

Re:Of Course! (1)

FireFury03 (653718) | more than 7 years ago | (#16050915)

Differential GPS greatly improves your precision, from meters to centimeters

This is incorrect - DGPS improves the precision from somewhere around 15 metres to 3 - 5 metres - certainly nowhere near centimetres (which is pretty much impossible with GPS due to the wavelengths involved - I understand Gallileo will be providing a high precision service though).

But I'm unclear on why the loss of funding for DGPS is big news - is anyone still using DGPS? If so, why? If you've got a view of the equatorial horizon then SBAS is a much more sensible idea.

You Know, This Kind of Is a Problem ... (3, Interesting)

eldavojohn (898314) | more than 7 years ago | (#16046906)

You jest about this, but I think this is a problem.
The problem facing NDGPS today, in my opinion, is the lack of a 'killer app.' In other words it's a neat tool and serves hundreds (if not thousands) of people on a daily basis, but if it disappeared tomorrow, life would go on. Therefore, when it comes to cutting the budget during tight times, programs like NDGPS are prime targets.
I disagree. The fact that you demand it have a "killer app" instead of clean functionality tells me that you lack sound judgement on this service. It's a service for locating yourself. We put green & blue information plaques by the sides of roads that tell you where you are. They're called 'road signs.' It probably costs more than $10 million a year to maintain them. I, for one, would like a public service that keeps me informed as to where I am.

Now you're telling me that we can't afford to clip another $10 million off the Defense budget [wikipedia.org] and give it to this service (which may, arguably, help the coast guard in defending our shores)? Come on, we spend way more on military than any other country. It's good to maintain military superiority but do we really need it when you look at that chart? The next highest is China with maybe an 1/8th as much spending as we do. Give me a break!

There's no way anyone can justify cutting the spending on this program given what we've invested in it and how useful it is. When you look at where the rest of our spending goes, $10 million is nothing. No one can complain that the cost versus potential utility of this thing isn't high enough.

learn how to reply to the right comment, moron. (-1, Flamebait)

Anonymous Coward | more than 7 years ago | (#16046959)

nt

Re:You Know, This Kind of Is a Problem ... (3, Informative)

Anonymous Coward | more than 7 years ago | (#16047101)

Now you're telling me that we can't afford to clip another $10 million off the Defense budget and give it to this service (which may, arguably, help the coast guard in defending our shores)?

This kind of DGPS (type-1 or type-9 messages only) that the Coast Guard sends is of very limited utility. Now that "Selective Availability" (intentional noise added to the civilian GPS signals) is gone, there is very little positional improvement one gets from their DGPS. If they kill it, I doubt anyone but the folks working there will be affected in any significant way.

Re:You Know, This Kind of Is a Problem ... (2, Interesting)

ronanbear (924575) | more than 7 years ago | (#16047331)

If it's only $10m then maybe the companies that sell GPS systems would pay for it themselves if they care that much about it. It's fair that companies wouldn't be able to fund GPS in its entirety but customers that want extra accuracy should be willing to pay for it.

SA wasn't a big deal to yachtmen as it was accurate enough. It was a much bigger deal for car navigation systems (think parallel roads 50 yards apart and chaos at junctions).

A few days after SA was turned off I went for a walk and the track of my walk showed that I walked down one side of the road and back the other. That's the difference it made and there are plenty of uses of GPS which don't require that (or more accuracy). Some (especially GPS based surveying) require far greater accuracy than even DGPS/WAAS can provide.

Re:Of Course! (-1, Offtopic)

Killshot (724273) | more than 7 years ago | (#16046922)

RIP KGB CIA JUD FDA LSD FBI DMT ROM PCP UDA FCC KKK MAD CNN BBC EMI THC ICI TNT DNR MDA SAS JFK RAM CND IRS LED HBO GHB YSL RIP RIP RIP I am godhead You are godhead We are godhead Use it (Higher, Higher, Higher, Higher) OTO ABC RPM CNC MIT IRA EEC HRH KFC IBM HIV VCR VAT PLF NBC MGM ANC MOR MTV AAA HRT ATM TAZ DAR XTC FAA VIP CBS CID RAF DDT DOM DAT TVC QED UFO GOD USA RIP RIP RIP RIP I am godhead You are godhead We are godhead Use it

Re:Of Course! (1)

punkish (989278) | more than 7 years ago | (#16048078)

I think I will shutdown my GPS, go home in my BMW, and watch CBS on my VCR.

They say that he's a VIP, (1)

Myself (57572) | more than 7 years ago | (#16048961)

This could be, only in the USA [sinteticor.com] .

Honestly... (1)

SonicSpike (242293) | more than 7 years ago | (#16049224)

To be completely honest... I laughed until I cried after reading your post.

That was great man!

DGPS sites on internet (2, Insightful)

ronanbear (924575) | more than 7 years ago | (#16046790)

Would not actually be hard. Technically you could do it yourself. Really at it takes is a fixed location GPS (calibrated) hooked up to a server which processes the NMEA data and uploads the correction dynamically.

Doom and gllom for punchcards! (5, Informative)

EmbeddedJanitor (597831) | more than 7 years ago | (#16046829)

Everything has its natural life, and WAAS is now a good replacement for beacon. So what if beacon differential goes away? WAAS is better: it is easier to add to a system (it uses L1 and typically needs no extra hardware vs beacon needs a special receiver etc), is cheaper, and is easier for customers to use.

I didn't mind punch cards being phased out either....

Re:Doom and gllom for punchcards! (3, Informative)

Chanc_Gorkon (94133) | more than 7 years ago | (#16047334)

This post hits the nail on the head. Only thing I would add is SA has been turned off for quite some time now and WAAS is in even the cheapest GPS receivers now. DGPS also ONLY worked if you were in range of a body of water too (Coast Guard sites if I remember correctly). PLUS newer GPS receivers can hold a lock on more satellites then the first model GPS receivers were capable of. At this point, I could care less about DGPS. I have not seen a receiver that has supported this in many years with the only exception being Marine GPS receivers. DGPS needs to go just like LORAN did many years ago.

LORAN is still up, you insensitive clod! (1)

wsanders (114993) | more than 7 years ago | (#16047617)

I was messing around on a friend's boat last May and turned on the LORAN receiver. Lo and behold it displayed a set of valid coordinates.

LORAN lives! (Well for a few more months anyway.)

http://www.gpsworld.com/gpsworld/article/articleDe tail.jsp?id=314650 [gpsworld.com]

And I think it is used more widely in the non-US, non-EU parts of the world.

Re:LORAN is still up, you insensitive clod! (1)

slacktide (796664) | more than 7 years ago | (#16050043)

Yep, LORAN still works just fine. I fly a small plane with an Apollo 618C, which works great, and IMO has a far superior user interface than the godawful bendix-king GPS which is also installed on the A/C.

Re:LORAN is still up, you insensitive clod! (1)

Chanc_Gorkon (94133) | more than 7 years ago | (#16050094)

Yeah. I noticed this after I posted. LORAN may still be available, but I don't know anyone at all that uses it. If I remember right, LORAN recievers were a bit pricey compared to GPS recievers.

Re:DGPS sites on internet (1)

puhuri (701880) | more than 7 years ago | (#16046895)

In theory yes, but you won't get the needed information from a normal GPS receiver. To calculate DGPS correction, you must calculate error for each satellite and feed that to other GPS receiver. If you just take difference between the right location and the location you got from NMEA output and use that to correct postition indicated by other, you will get greater error than without.

This is because each receiver picks a different set of satellites.

Budget Cuts (3, Insightful)

dch24 (904899) | more than 7 years ago | (#16046916)

DGPS does the correction on a satellite-by-satellite basis. The GPS receiver must support DGPS corrections, which are uploaded to the receiver to include in its internal calculations before the separate satellites are combined to form the final result.

Remember when GPS itself was thought to be in danger back in 2000 [pobonline.com] ? Remember when there was talk of balancing the budget? Read this article [afa.org] all the way from 1996 about the military importance of GPS technology. It's worth the read.

About the NDGPS vs. WAAS debate: I work for a group that relies heavily on GPS for aviation purposes. As the number of uses for GPS expand, as they inevitably will, new technologies will spring up. NDGPS vs. WAAS is like 802.11g vs 802.11a. I think they both have a place. If the government won't support NDGPS, perhaps there is a commercial application? What are the FCC regulations on the 300KHz spectrum? If no one will pay for it, let it die, I think.

Okay, <rant>
I laughed when I read, "Therefore, when it comes to cutting the budget during tight times, programs like NDGPS are prime targets." How are we cutting costs when we just ran up a record high deficit in the last two years [zfacts.com] ? I like it that we're cutting costs. Let's cut some of the really big ones, like military spending!
</rant> Couldn't resist.

Re:Budget Cuts (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#16047058)

If we cut military spending, then the terrorists have one. So what if the terrorists have one, you ask? Well, the terrorists are Arabs, and Arabs invented zero, so now they have binary. As in binary weapons. Come on people, do I have to spell it out for you?

Re:Budget Cuts (1)

danno (7334) | more than 7 years ago | (#16047346)

I like it that we're cutting costs. Let's cut some of the really big ones, like military spending!


Except remember, GPS came from a black budget military spending project that made the military budget look bloated. Look before you bite the hand that feed, and make sure it's not going to slap you after you bite it.

Re:Budget Cuts (0)

Anonymous Coward | more than 7 years ago | (#16049807)

"I like it that we're cutting costs. Let's cut some of the really big ones, like military spending!"

How 'bout instead we cut bloated social welfare entitlement programs, force lazy louts/breeders back to work doing jobs that "Americans dont want to do".

Kicking a 1000 lazy shitebags off welfare should free up enough loot to fund NDGPS.

Re:DGPS sites on internet (2, Informative)

tonywestonuk (261622) | more than 7 years ago | (#16046928)

Hmmm.... google for 'dgps internet'... and guess what you find: DGPS corrections over the Internet [wsrcc.com]

Re:DGPS sites on internet (1)

Koyaanisqatsi (581196) | more than 7 years ago | (#16047032)

OP was asking for *more* sites. Those corrections are only valid in a range of a few tens of Km around the site where they originate from.

But, as someone else said, WAAS is much simpler to implement so I don't really have much of a problem with this - altough one could arguee that the two systems complement each other, which I'm not sure is the case, but ...

Re:DGPS sites on internet (0)

Anonymous Coward | more than 7 years ago | (#16047243)

Hmmm.... google for 'dgps internet'... and guess what you find: DGPS corrections over the Internet

Thats my site.

It was mostly meant as a fun experiment to see how well long-distance corrections worked. Ans: Well enough to prove that some of the claims about the nature of Selective Availability were wrong. Selective Availability corrections from one part of the country were quite useful in another part of the country.

Now that the largest component of the DGPS corrections are ionospheric and tropospheric corrections, the area the corrections are useful in is much, much smaller. I've heard numbers as high as 1-meter accuracy lost per 100-miles distance from the referencce station. With GPS's typically able to be within 5 meters 50% of the time thse days, it isn't clear what good these DGPS stations are.

-wolfgang

Um, why should it be saved? (1, Insightful)

Anonymous Coward | more than 7 years ago | (#16046795)

As an outsider, I see two technologies that do more or less the same thing. One is better in every way. Its only downside that it's not usable in certain situations where the other might possibly be used.

And this is a reason to spend a couple hundred million plus $10 mil/year in operating expenses?

I know it's not a large amount of money compared to the national budget, but it's still a lot of money.

Re:Um, why should it be saved? (1)

Isaac-1 (233099) | more than 7 years ago | (#16048290)

The difference is WAAS depends on a clear view to a satelite in geosync, all fine and good for the FAA that developed it for aircraft use where the GPS antenna can be on the top of a plane, not so good when you have mounted your antenna on a ship or a truck where either other parts of the vehicle or the terrain might block the signal.

Re:Um, why should it be saved? (1)

Alpha830RulZ (939527) | more than 7 years ago | (#16048406)

And for some specific data on why this is bad, consider that WAAS depends on line of sight view to the satellite. In Portland Oregon, hardly the end of the earth, that line of sight is 7 degrees above the horizon when I last checked. If you are behind even a modest hill, the signal is unavailable. WAAS works great for planes, but is less than perfect by far for ground based use. In cities, it's basically unusable. You can get the stats from http://www.lyngsat.com/tracker/inmar3f4.html [lyngsat.com]

Re:Um, why should it be saved? (1)

a55clown (723455) | more than 7 years ago | (#16049244)

GPS satellites are not geostationary. At any point in time there should be 5 satellites within range/LOS, regardless of where you live.

Not wishing to flame (0, Offtopic)

Sexy Bern (596779) | more than 7 years ago | (#16046799)

Please, when using terms like "national", make it clear which nation you're talking about.

The internet is GLOBAL!

Re:Not wishing to flame (-1, Offtopic)

skroz (7870) | more than 7 years ago | (#16046814)


The internet is GLOBAL!


But contrary to what you may believe, Slashdot ISN'T.

Re:Not wishing to flame (-1, Offtopic)

Morphine007 (207082) | more than 7 years ago | (#16046820)

I'm Canadian, so I share your desire to know which Nation is being talked about.... but the big ol' American Flag in the article stub should've probably given it away, eh?

Re:Not wishing to flame (2, Insightful)

Stormwatch (703920) | more than 7 years ago | (#16046827)

Please, when using terms like "national", make it clear which nation you're talking about.
The USA flag next to the story's title kind of gives that away.

Re:Not wishing to flame (1)

WhatAmIDoingHere (742870) | more than 7 years ago | (#16046839)

The internet may be "global" but Slashdot is US-centric.

Check here [slashdot.org] .

Re:Not wishing to flame (0)

Anonymous Coward | more than 7 years ago | (#16046860)

That is why there is a picture of the American flag next to the article.

Re:Not wishing to flame (1)

PhxBlue (562201) | more than 7 years ago | (#16046908)

And GPS is American. Work it out.

Re:Not wishing to flame (2, Informative)

pla (258480) | more than 7 years ago | (#16047020)

Please, when using terms like "national", make it clear which nation you're talking about.

The use of "GPS" and "WAAS" does make it clear. The FP did not say "GLONASS", or "EGNOS", or "GAGAN", or "MSAS", or even the generic term "SBAS".

The whole world can use GPS, but the US outright owns it and controls every aspect of its operation, whether the rest of the world likes it or not. Dubbya could order SA turned back on tomorrow, and all the foreign users that have come to critically require reasonably accurate GPS would have no say in the matter whatsoever.

Re:Not wishing to flame (1)

lohphat (521572) | more than 7 years ago | (#16048805)

And endanger every flying aircraft using GPS? Please. GPS recievers have been able to correct for SA *before* it was turned off. It's a non issue. Plus, if the EU operators of the competing Galeleio system don't agree with Napoleon they don't have to cooperate -- their system would just keep on chugging away.

Re:Not wishing to flame (1)

pla (258480) | more than 7 years ago | (#16050805)

And endanger every flying aircraft using GPS?

Yes, and endanger every aircraft, cruise ship, and clueless-SUV-driving-mommy that uses GPS. And for proof, you need look no further than the occasional "test" that SA still works conducted every now and then. Have no doubt whatsoever that the moment a "terrorist" uses (or comes close to using) a GPS-enabled attack, SA will go back on.



GPS recievers have been able to correct for SA *before* it was turned off.

Key phrase missing - "over time". Yes, SA averages out over the course of 5-15 minutes. If you stand still (or maintain a fixed course and speed) for that long, you can get a fairly good idea of your position. The applications most dependant on GPS, however, tend to need results immediately, and while making course corrections.

Now, DGPS and WAAS also have the effect of cancelling out SA. Key difference, anyone with a few grand (down to a few hundred these days?) can set up a DGPS beacon. Only governments can send up SBAS corrections such as WAAS, meaning if Bush decided to turn SA on tomorrow, he could also turn WAAS off. He couldn't (entirely) do the same for DGPS. Remind me which one this topic discusses eliminating?



Plus, if the EU operators of the competing Galeleio system don't agree with Napoleon they don't have to cooperate

True - But Galileo doesn't go live for another four years, and a LOT can happen in the meantime.

Why don't they just publish the P(Y) keys? (1)

Eric Smith (4379) | more than 7 years ago | (#16046818)

Wouldn't the "Precise" code give better resolution than either DGPS or WAAS?

Re:Why don't they just publish the P(Y) keys? (3, Informative)

LWATCDR (28044) | more than 7 years ago | (#16046872)

No.
DGPS can be far more precise than military precise setting. A resolution of one meter is more than good enough for any weapon system that would use GPS.
I remember hearing about a form of DGPS that has a lot higher resolution than one meter. It is often used for surveying.

Re:Why don't they just publish the P(Y) keys? (3, Informative)

monopole (44023) | more than 7 years ago | (#16046930)

Precisely, Carrier Differential GPS can be on the order of less than 10 centimeters on a good day. The other factor is that CDGPS works off of precision epemeredies that are released the next day. Good for survey, not handy for weapons. (There is real time kinematic GPS with such precision but not much in the civilian world.)

That being said P code recievers make differential and carrier differential easier.

Re:Why don't they just publish the P(Y) keys? (1)

LWATCDR (28044) | more than 7 years ago | (#16047181)

I probably should have left out the part about weapons not needing more than ~1 meter resolution. Any way thank you for the information on CDGPS.

Re:Why don't they just publish the P(Y) keys? (1)

Doctor Memory (6336) | more than 7 years ago | (#16049246)

In my ham radio club we have a guy who used to run the Astronautical Measurement section. He gave a talk about GPS and DGPS one night, and finished by talking about CDGPS. Basically, it's so good you could fly a plane by placing receivers at the nose, tail and wingtips. It could tell you what the attitude of the plane was to a good enough extent that you could fly it remotely based just on the information from those four receivers (well, you'd need a control system too, but you know what I mean....) I forget what the resolution was, but ISTR it was in fractions of a centimeter.

Re:Why don't they just publish the P(Y) keys? (1)

Doctor Memory (6336) | more than 7 years ago | (#16049263)

Doh! Sorry, that should be "a guy who used to run NASA's Astronautical Measurement section". His group was the one that had to measure how close Mars was when it was at its closest point, stuff like that.

Re:Why don't they just publish the P(Y) keys? (1)

doghouse41 (140537) | more than 7 years ago | (#16047723)

We use Leica DGPS equipment with our own DGPS base station. Accuracy depends on how far you are from the base station, but on our fairly small island we reckon on 1-2 cm accuracy, horizontally and vertically.
This does depend on having sufficient satellites in view - this is a problem under trees and close to buildings and steep slopes.

Article Unclear (5, Insightful)

uab21 (951482) | more than 7 years ago | (#16046848)

Obviously I have missed something in TFA. It states that there are areas where NDGPD is available that WAAS is not, but that also WAAS is available where NDGPS is not. NDGPS requires additional hardware which is A) expensive, and B) bulky, whereas WAAS is available on pretty much all currently available receivers. Both systems (NDGPS and WAAS) have comparable accuracy (~1 meter).

Why, again, should we be sorry that NDGPS is going away? It sounds like market forces at work here. The only specific instance that TFA mentions where NDGPS has an advantage is *some* in-building penetration. Why should we build out a *national* network for only some in-building penetration? It sounds to me that WAAS is getting funding because it is technically and economically the better solution. Why is this a problem?

Re:Article Unclear (1, Funny)

Anonymous Coward | more than 7 years ago | (#16046940)

Why is this a problem?

Obviously it was written by a NDGPS hardware provider who is watching their future go awry. Won't anyone think of the corporations?!

Re:Article Unclear (2, Interesting)

Isaac-1 (233099) | more than 7 years ago | (#16048341)

WAAS requires that geosync be visible from the GPS receiver there are many instances where this can be a problem, for one thing it generaly means the GPS antenna be mounted at the highest point on the vehicle (a potential problem with ships as by law lights must be mounted at their highest point) also terain and even trees, may be an issue for trucks, etc particularly in more northern states where geosync appears low on the horizon.

Both longitude and latitude (1)

Beryllium Sphere(tm) (193358) | more than 7 years ago | (#16048554)

Being northerly makes it harder to see a geosync satellite. What's less obvious is that being too far east or west creates the same problem.

Look at it this way: whether you go up/down or right/left, you're still moving away from the point where the satellite is overhead.

WAAS & CORS = better? (3, Interesting)

Jurisenpai (261790) | more than 7 years ago | (#16046869)

I personally *hate* using the NDGPS (beacon) real-time corrections. We only have two reference stations in my state and neither are worth a damn in my city. I work as for a major GPS company, and though we do sell beacon receivers quite briskly, I hate using them.

I much prefer using WAAS for real-time, especially after the two new satellites are up and fully functional. I do post-process most of my data, however, so the CORS stations work just fine for my needs.

LOST (4, Funny)

EddieBurkett (614927) | more than 7 years ago | (#16046892)

If NDGPS is indeed lost, can't we just use its GPS to find it?

Mod parent down; stupid. (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#16046929)

Thanks, Natalie.

Re:LOST (2, Funny)

Rorschach1 (174480) | more than 7 years ago | (#16047118)

Well, sure, but only with about 5 meters precision.

It's called progress (2, Insightful)

NoRefill (92509) | more than 7 years ago | (#16046897)

WAAS is the next step in this technology. Let the dinosaur die and let's move on.

Ok You libertarians out there, LETS GO! (-1, Flamebait)

Anonymous Coward | more than 7 years ago | (#16046910)

Tell us how the free market will make this available. We want to read your RANTS!!!

Go, go, GO!

That's not trolling libertarians, THIS is... (2, Interesting)

spun (1352) | more than 7 years ago | (#16047351)

Oh, please. I think Libertarians are completely goofy, but this is just too easy. As long as you're a Libertarian who believes in initiation of force to protect intellectual property laws. Of which there are tons. Personally, I don't see how they wrap their heads around that without them exploding, but it works for them.

The problem, of course, is that the GPS broadcasts are a public good, so how do protect that, in order to charge for it? Encryption? If people get their hands on your device, they can break the encryption. It all boils down to giving a government enforced monopoly on using the broadcasts to the people who put the satellites up. Otherwise, the people putting up the satellites could never recoup their initial investments, as anyone could make a receiver and not have to pay the people putting them up.

But as I mentioned, plenty of Libertarians can quite easily wrap their heads around the paradox of enforced ownership of intellectual property. It all comes from a very flexible definition of "initiation of force." Basically, any use of force a libertarian doesn't like is "initiation of force," while anything else is "retaliatory force" which is, of course, justified as YOUR NATURAL RIGHT!

See, in order to troll successfully, you have to have an understanding, nay, even a love for that which you troll. You have to care enough about your subject to actually get inside and find out what makes 'em tick, what are their foibles, paradoxes and hot buttons.

So, any Libertarians out there want to respond to a self proclaimed troll and tell me how you would do it without intellectual property protections? I mean, if you thought protection of real property took a lot of state sponsored violence, imagine how much state sponsored violence is necessary for the protection of imaginary property? Come on, you guys are smart, I mean, it's not like you just memorize your party dogma and can't answer simple questions that fall outside the bounds of official, party sponsored reasoning, is it?

Happy Troll Tuesday!

P.S. As much as I think the vast majority of Libertarians are goofy, I've had conversations with some here who are probably smart enough to figure out how to do this, so even if no one responds, that doesn't mean all libertarians are dogma spouting mouth breathers who couldn't reason their way out of a paper bag. Some would manage to deduce that ripping open the bag was not in fact initiation of force, as the bag was depriving them of their natural right not to be in a paper bag.

Redundant programs being cut (2, Interesting)

lohphat (521572) | more than 7 years ago | (#16046919)

Think about the implications if WAAS (and soon-to-arrive LAAS) is decommissioned -- the FAA has already issued WAAS-based LPV approach plates for IFR ops. Switching to another system would cause a huge momentum change in a critical sector of the safe operation of our airways.

The FAA upset thousands of pilots when they pulled the plug on TIS (Traffic Information Service) when approach radars (ASR 9 to ASR11) were upgraded and their investment in TIS equipment was obviated -- the one they chose, ADS-B (Automatic Dependent Surveillance - Broadcast) provides more data and is more scalable. Essentially instead of using radars and transponder return codes to figure out who's who, let the aircraft broadcast their position s constantly without having to wait for a radara sweep. But I digress.

Same with these conflicting solutions -- one my be "better" in terms of feature set but the other has momentum. MP3 vs OGG anyone? Beta vs VHS?

I'd rather have a standard augmented data-channel and ground based "satellites" to allow my portable GPS to function in the skyscraper canyons and provide local traffic and business lookups so that I don't need to subscribe to CD/DVD updates when the data could just be real-time.

Re:Redundant programs being cut (0)

Anonymous Coward | more than 7 years ago | (#16046998)

I agree, people who have already shelled out the money for a Garmin 480, a GPS that can allow for precission approaches using WAAS, are going to be upset if they have to change technology again. LPV approaches allow for pilots to get just 50 feet above what current ILS landing systems allow, i think the standard has been set and the others need to just get out of the way.

Re:Redundant programs being cut (1)

GnuPooh (696143) | more than 7 years ago | (#16048392)

Correction: The FAA admin has already issued a PR and the new LPV Order is out that says LPV is now down to 200' HAT.

Rick.

Re:Redundant programs being cut (1)

GnuPooh (696143) | more than 7 years ago | (#16048400)

LAAS was zero'd out in the FAA budget two years ago and is still zero. So it's unlikely LAAS will happen any time soon if at all.

Poor guys... (1)

xtermz (234073) | more than 7 years ago | (#16046937)

Blind people and robots also benefit from highly accurate GPS navigational capability provided by NDGPS

Of course, nobody cares about poor blind robots, running around, bumping into walls. And what about blind human/robot hybrids? Are they stuck with their bionic seeing eye dogs?

Re:Poor guys... (0)

Anonymous Coward | more than 7 years ago | (#16047398)

I for one welcome our robot hybrid overlords.

Netcraft confirms: *BSD is dying (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#16046953)

One more crippling bombshell hit the already beleaguered *BSD community when IDC confirmed that *BSD market share has dropped yet again, now down to less than a fraction of .01 percent of all servers. Coming on the heels of a recent Netcraft survey which plainly states that *BSD has lost more market share, this news serves to reinforce what we've known all along.

FreeBSD is the most endangered of them all, having lost 93% of its core developers. The sudden and unpleasant departures of long time FreeBSD developers Jordan Hubbard and Mike Smith only serve to underscore the point more clearly. There can no longer be any doubt: FreeBSD is dying.

Let's keep to the facts and look at the numbers.

OpenBSD leader Theo states that there are 7000 users of OpenBSD. How many users of NetBSD are there? Let's see. The number of OpenBSD versus NetBSD posts on Usenet is roughly in ratio of 5 to 1. Therefore there are about 7000/5 = 1400 NetBSD users. BSD/OS posts on Usenet are about half of the volume of NetBSD posts. Therefore there are about 700 users of BSD/OS. A recent article put FreeBSD at about 80 percent of the *BSD market. Therefore there are (7000+1400+700)*4 = 36400 FreeBSD users. This is consistent with the number of FreeBSD Usenet posts.

Due to the troubles of Walnut Creek, abysmal sales and so on, FreeBSD went out of business and was taken over by BSDI who sell another troubled OS. Now BSDI is also dead, its corpse turned over to yet another charnel house.

All major surveys show that *BSD has steadily declined in market share. *BSD is very sick and its long term survival prospects are very dim. If *BSD is to survive at all it will be among OS dilettante dbblers. *BSD continues to decay. Nothing short of a miracle could save it at this point in time. For all practical purposes, *BSD is dead.

GPS and ITS? (1)

lpangelrob (714473) | more than 7 years ago | (#16046957)

I understand the Positive Train Control part; you need to be able to tell where a train is in order to tell it what to do. I'm having a little more trouble with the Intelligent Transportation Systems part.

You don't necessarily need GPS to tell automobile drivers what's going on ahead of them; there are other, infrared or magnetic loop current-based ways to do that already.

Re:GPS and ITS? (1)

lohphat (521572) | more than 7 years ago | (#16047049)

> I understand the Positive Train Control part; you need to be able to tell where a train is in order to tell it what to do. San Francisco Muni drivers could use all they help they can get. Just about got killed this morning when the train did two emergency stops sending people flying. This all heppend after the driver finally turned off his right turn signal after being in the tunnel for 5 minutes (they're surface trams and underground part of their routes). "Sorry, uh... computer glitch...." My a**.

Reason why (0)

Anonymous Coward | more than 7 years ago | (#16046963)

Q: What event is the DHS anticipating that might be coming in 2007 that made the DHS decide to tell the CG to drop NDGPS?

A: A state of international affairs involving the risk of lots of hostile things flying really fast and accurately towards various precious destinations best hampered by withdrawing NDGPS?

Re:Reason why (1)

lohphat (521572) | more than 7 years ago | (#16047006)

As opposed to the current accuracy of handheld devices to be around 1m? When something bad happens, 1m matters not.

Re:Reason why (0)

Anonymous Coward | more than 7 years ago | (#16047056)

But unlike WAAS, only NDGPS, being at around 300kHz, works well even without LOS in urban areas where hostile things are most likely to cruise very fast and accurately.

Re:Reason why (1)

lohphat (521572) | more than 7 years ago | (#16047362)

Nope. missles also have IRS (inertial nav) systems to augment GPS signal loss. Current aircraft can go housr without GPS running on IRS an no signficant loss of precision.

Re:Reason why (0)

Anonymous Coward | more than 7 years ago | (#16047614)

These things have lots of really fancy extras apart from GPS and IRS, which neither of us (I hope) is going to discuss openly here. That's the friendly ones; the hostile ones, to which I was alluding, are from places that could build in NDGPS+IRS but not the really fancy extras. They still have to meet the objective of being able to navigate accurately in urban areas at high speeds. Integrating the differential data from IRS to estimate real-time position during periods of poor GPS signal reception does not give sufficient accuracy for navigation in urban areas.

Beneficial for Robots? (1, Flamebait)

DongleFondle (655040) | more than 7 years ago | (#16047016)

Wont someone please think of the robots!

used by hundreds! (4, Informative)

frovingslosh (582462) | more than 7 years ago | (#16047046)

Right from the article: "used by hundreds if not thousands of users on a daily basis". This pretty much sums it up, there is an old technology that needs a special extra receiver that is used by hundreds of people (or maybe more) and costing millions of tax dollars, while there is now a widely deployed WAAS system that uses the same satellite receiver as GPS (no extra receiver required), is used by vastly more people, covers the country, and somehow the politicans have caught on that the old system is a waste. Although we may not be able to stop paying billions for bridges in Alaska that go to islands with 50 people and will admittedly help only realestate investors, at least they see the folly in supporting this old system. It should be shut down, in spite of any private agenda the original poster has.

On top of this, WAAS isn't the end of the line, there are more systems coming on-line that will improve GPS acuracy even more. The old system was OK for what it was, but the need for extra receivers by each user certainly limited it's adoption. It should be phased out.

And one thing I just have to comment on from the article and even the /. blurb: "Positive Train Control"! Are we really to believe we need taxpayer funded meter accuracy for GPS for train control? Do these trains really wander from from the tracks we know the location of? Isn't normal GPS accuracy just fine for choo-choo trains? And in the rare cases where higher accuracy might come in handy (although should hardly be needed), such as a switchyard, couldn't the location itself provide a small simple system for far less cost than asking the taxpayers to support it for this special use? You don't even need Internet data for this, you just have to agree on the location of the stationary differential receiver site and put a receiver without WASS there, it's error from it's known location is the same or better correction information than you could get from the Internet.

Re:used by hundreds! (2, Funny)

bunions (970377) | more than 7 years ago | (#16047123)

> Do these trains really wander from from the tracks we know the location of?

well, duh: Amtrak. helloooo! Anybody home, McFly??

Re:used by hundreds! (0)

Anonymous Coward | more than 7 years ago | (#16048430)

"Positive Train Control"! Are we really to believe we need taxpayer funded meter accuracy for GPS for train control? Do these trains really wander from from the tracks we know the location of? Isn't normal GPS accuracy just fine for choo-choo trains? And in the rare cases where higher accuracy might come in handy (although should hardly be needed), such as a switchyard, couldn't the location itself provide a small simple system for far less cost than asking the taxpayers to support it for this special use?

Err, how many times have you seen bypass rails? There everywhere, including many in the middle of nowhere. Now, these rails are quite close together, where an error of 1 meter can make all the difference between the system thinking the train in on the main rail vs the bypass. "Spot" solutions have been tried, but since DGPS was available and "free", why wouldn't they utilize it, lot cheaper than putting units out at every possible site.

Obligatory Dead-Head Comment (0)

Anonymous Coward | more than 7 years ago | (#16049207)

Do these trains really wander from from the tracks we know the location of? Isn't normal GPS accuracy just fine for choo-choo trains?


The difference between 1m accuracy and 10m accuracy is being able to tell when "...train hundred-and-two / is on the wrong track / and headed for you!

employee tracking (1)

Shotgun (30919) | more than 7 years ago | (#16047119)

FTA:

The e-card provided information about the owner's current context and activities.

In other words, "managers could track employee's activities without having to look over their shoulders."

Ummm...could I skip this 'upgrade'?

Just do the job you're paid to do (1)

/dev/trash (182850) | more than 7 years ago | (#16048545)

and there's nothing to worry about.

There is no need for NDGPS. How WAAS works (2, Informative)

viking2000 (954894) | more than 7 years ago | (#16047152)

There is no need for NDGPS. How WAAS works

Just to explain to the submitter if this is not already crystal clear: There is no need for NDGPS. WAAS has fortunaltely replaced it.

NDGPS required a seperate receiver to get the error signal from a ground based transmitter. You also had to be near a ground based error transmitter for this to work.

The ground based error transmitters are still there, and more are beeing added. Instead of transmitting locally, a database of errors over a wide area is constructed, and a geostationary sattelite transmits the error database on the same wavelenght as the other GPS sattelites to all GPS devices. All that is needed for this is typically a firmware update in the GPS unit.

Simple, effective, cheap.

Actually... I support WAAS (2, Interesting)

JustNiz (692889) | more than 7 years ago | (#16047376)

Because thats what my Garmin GPS uses. It (and I) have never heard of NDGPS so I hope WAAS doesn't get phased out. given that it also makes sennse to have a single standard, it makes sense to me for NDGPS to go away.

WAAS is better (1)

ChrisA90278 (905188) | more than 7 years ago | (#16047679)

WAAS is better. All you need is one GPS reciever and it costs noting and is available everywhere GPS is. Differential was a great idea but they used a second back channel radio to broadcast the data. WAAS is almost the same thing but uses the GPS system itself to broadcast the data. Smarter really.

Re:WAAS is better (0)

Anonymous Coward | more than 7 years ago | (#16048303)

WAAS . . . is available everywhere GPS is.
Nope.

Blind people and robots also benefit (1)

BenFaremo (730430) | more than 7 years ago | (#16047710)

Won't somebody, anybody, think of the robots?

WAAS versus NDGPS (0)

Anonymous Coward | more than 7 years ago | (#16047816)

Before deciding that DGPS should go the way of the dodo, you should consider the international issues and penetration for DGPS and WAAS.

DGPS provides 1-3 meter accuracy with proper beacon reception equipment. The service delivers its coverage in circles around transmitter sites. The DGPS standard is an international standard, allowing precision approaches within 200-500 miles of a transmitter site. DGPS coverage [uscg.gov] is already quite good.

WAAS provides 1-3 meter accuracy with no additional equipment. WAAS itself provides this service in a service volume [faa.gov] using two existing geostationary satellites.

Receiving WAAS service in the continental U.S. is sometimes difficult on the ground. Those of you who use GPS in mountainous terrain may have experience with this. Solving this reception issue inside the U.S. might be as simple as adding a third or even fourth satellite to transmit the corrections. Once receivers on the ground are better able to receive the correction signal, WAAS is clearly a more convenient solution.

NDGPS had a good footing and was a fantastic solution in its day. Discontinuing the sites within the U.S. is certainly a feasible budget solution. However in coastal regions, DGPS stations should be continued at least until the current generation of marine receivers is replaced.

Go WAAS (1)

sammyo (166904) | more than 7 years ago | (#16047821)

At first glance I thought NDGPS was some synonymic acronym
for WAAS and it sounded disturbing. On a slightly closer
reading I see that WAAS is not in danger. It never was
and won't be. Hundreds if not Thousands of 'connected'
yacht owners would never find their moorings if WAAS was
shut down. Some of these are the source of government, er,
oil. I'm sure no one in government would want to loose
these users of WAAS.

NDGPS just better for some applications (2, Informative)

billwie (257149) | more than 7 years ago | (#16048360)

Three items of note:

1. Sky visibility can significantly degrade your accuracy via WAAS. Personally, working in a lot of areas with random overhead cover (trees) I prefer NDGPS to WAAS even if I have to download the corrections and post correct. In a test I ran in a suburban forested park NDGPS was able to meet the 1 Meter accuracy claims even with heavy overhead (40+ foot trees)in a comparison vs 6inch pixel aerial photography. WAAS consistantly got a ~2-5 meter error on the same locations.

2. NDGPS stations are already failing in our area. Of the Three stations that are barely within the range at which they are useful, none consistantly provide base station data via the internet, and 1 has failed completely. If the current funding level is approved ($0) I don't see any improvement in the near future. Thus my company has invested in our own DGPS base station to guartee 1 meter accuracy in the event of NDGPS unavailability, despite the downsides (maintenance, requires a survey accurate point to permenantly mount the basestation, basestation must run at least one hour before and after field collection of data to insure coverage).

3. In our current contract with a US government agency that specified 1 meter accuracy GPS, WAAS was not an acceptable correction option. So it was either rely on unreliable Government funded base stations, or buy our own. (BTW, I'm glad we did buy our own).

How about letting the GPS in my phone serve me? (1)

topham (32406) | more than 7 years ago | (#16048378)

My cell phone supports AGPS, while I don't know the specifics about the implementation (Motorola RAZR v3c) I wish I could take advantage of the fact it can do it.

Instead the phone company makes it impossible to do anything with it. In my case they don't even offer services for it.

somedays I'd like the technology to serve me; instead of big brother...

Re:How about letting the GPS in my phone serve me? (0)

Anonymous Coward | more than 7 years ago | (#16050153)

That is an entirely different matter. No soup for you.

over the Internet? why (0)

Anonymous Coward | more than 7 years ago | (#16048484)

Of course, what would be really cool is to see more GPS sites around the country make DGPS data (RTCM) available over the Internet.

Cool maybe, but not particularly useful. Wireless internet access is expensive. Wireless one-way broadcast of RTCM is many orders of magnitude cheaper (both from a cost-to-consumer standpoint and from a cost-of supplier standpoint). And if you're not using a wireless connection, what's the point of DGPS?

Business Issues (1)

purduephotog (218304) | more than 7 years ago | (#16048511)

Ya know, when I found this out I had to forward it onto our business group. Funny thing is, they had no CLUE it was happening.... and they aren't worried because the next product won't need it.

Of course, when you're talking sub-meter accuracy... well, here's hoping I have better employment by then since they're unwilling to listen...

NDGPS will loose because ... (0)

Anonymous Coward | more than 7 years ago | (#16050050)

... it pin-points the place and time where Congressional
and Executive Office Staff and Officials make cocaine
and prostitution deals on the streets of Washington
DC.

Oooopppp!!!!!

Having said that in a public place, I am ordered to have a
priviate execution by a seninor membor of the
US Executive Office [read GWB der Furer].

Ach Bin! Sig Heil! Toodles ze!

Differential GPS will be obsolete in 4 years time. (0)

Anonymous Coward | more than 7 years ago | (#16050405)

When the Galileo positioning system will be available by 2010 it will provide accuracy of 4 meters on the public service and better than 1 meter on the commercial service. Granted it some sort of enhanced GPS is needed in the interim but making investments in DGSP infrastructure at this time would be a waste of taxpayers money.
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