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Is It Really GPS If It Doesn't Use Satellites?
cartechboy writes: "GPS was originally developed by the military, but today it's in your smartphones, and soon, possibly your watches. Now the British military is developing something called quantum compass. The concept is a GPS-style navigation for submarines that doesn't use satellites. The quantum compass uses the movements of super-cooled subatomic particles to pinpoint a vessel's location. These particles, stored in a vacuum, react to the Earth's magnetic field. The movements caused by this interaction can be used for location positioning. At the moment, the Ministry of Defense's prototype resembles a '1-meter long shoe box,' so the next step is to miniaturize it. It could then be used by individual soldiers, as well as huge ships and submarines. Not only is it useful, but it's secure too—the technology is apparently interference-proof. Is this the future of navigation systems, or the reinvention of the compass? Possibly both."
Good luck with that.
"When information is power, privacy is freedom" - Jah-Wren Ryel
Does it provide you with an accurate position on the globe?
As far as I know GPS means "global positioning system", and doesn't include the word satellite.
Lost at C:>. Found at C.
Then it's a "Global Positioning System"... GPS.
Of course it is. It's Global Positioning System, not GLONASS Points South. Doesn't matter how you know where you are, as long as you know where you are with some accuracy. It's unlikely this method will be as accurate as using an actual satellite-based GPS, but probably good enough for submarines that can stay under for months at a time.
Nope.
Sounds like more like an inertial navigation system, but one that uses the Earth's magnetic field instead of just being shaken around.
#naabhaprzrag, #sverubfr-000, #agi-fcbafberq, negvpyr[pynff*=' negvpyr-ary-'] { qvfcynl: abar !vzcbegnag; }
If the technology depends on ultracooled atoms, how's a smartphone supposed to keep them cool?
Are we saying Global Positioning System, capitalized and considered a Proper Noun?
Then, no.
Are we saying global positionin system, a generalized term for systems that give you position data on the globe?
Then yes.
LORAN, EPLRS (when used as it was actually created for instead of a mesh data network), VORTAC, and probably many other systems were all generic positioning systems.
If the earths magnetic field moves (and it does), then won't this system also be affected?
THL phish sticks
The good thing about this technology is that it's also jamming-proof. If the U.S. and Russia ever get in a war, the first thing either side would do is knock out the other's GPS satellites with anti-satellite missiles, or conduct a cyber war. At that point, communications and positioning will be critical, making it important not to rely on a centralized network. Sure, GPS has multiple satellites, but if a cyber weapon knocks enough of them out, subs would have to go back to navigating by the stars and compass!
How is 'GPS' coming into this at all? In what way is it 'GPS-style'?
This sounds like a new variation of how submarines's have been navigating for decades. They already have a device that measures movement without satellites using gyroscopes that works pretty well, and this sounds like it is filling the same basic function except using the background magnetic field.
So it is a cool (no pun intended) piece of tech, but I am not understanding why it is being compared to a completely different technology like this.
The article is very unclear about how exactly these supercooled atomic particles tell them where they are on the globe. The impression I get is that it's just a more accurate form of inertial navigation. Or perhaps it compares the local magnetic and gravitational fields against some map of the Earth? I don't see how that would be immune to interference though, especially the magnetic part. And it would rely on an extremely accurate magnetic/gravitational map of the entire planet, which would have to be kept up to date as well as both those fields are constantly changing. Sounds very unpractical.
I'll be very interested to see if something comes of this or if it will just turn out to be hot air and/or inaccurate reporting...
How does something that operates based on a Earth's weak magnetic field prevent interference? They put "quantum" in the sentence, did they mean gravitation field?
I'm kind of surprised that Earth's magnetic field is stable enough for this to work well. Or if nothing else, wouldn't local magnetic field disturbances goof it up?
A long time ago I saw something that (according to the caption on the photo) was an inertial guidance unit for SLBMs. It was an instrumented(?) sphere that floated in liquid helium 4 which, at that temperature, was a superfluid (which I guess is a kind of quantum effect). This was to compensate for the motion of the submarine AND the flight of the SLBM because in a nuclear war I guess you can't count on any external sensors like a star tracker working. Since this sphere was suspended in a frictionless fluid presumably any frictional losses would be zero (and I guess very precise accelerometers could do the rest).
Now that I think of it, this might have been B.S. (how does one keep liquid helium 4 a liquid in a device, a solid fueled rocket, that you don't want to have to keep constantly maintained?). Still, "maybe" it actually worked, in which case why don't they just use this system in the sub? Are the running out of helium-4? (I think it's a rare isotope of a scarce gas).
Aaagh! That's where I screwed up! I knew I should have taken that left turn at Albuquerque!
I hear they made radio receivers before the invention of solid state technology.
Kids these days.
These particles, stored in a vacuum, react to the Earth's magnetic field.
I work for a company that deals with inertial navigation systems, specifically systems based on mechanical gyroscopes. The reason we use gyroscopes is because testing, running, and updating our tools for the last 30 years has shown us that we are inherently more precise than a magnetic measurement tool that measures the Earth's (local) magnetic field. Contrary to our tools, a magnetic measurement device is easily influenced by outside interference. Events like variations in the solar wind, such as solar flares, can easily interfere with the local magnetic field, which in turn changes your measurement of the field. Of course you can compensate for this with a lot of math, but even then those tools are still not as accurate as the tools we provide. I'd really like to know how they solved that problem, if they actually did.
Veni, Vidi, Velcro!
So, honest question ... at what depth does the satellite signal from the GPS system penetrate water? Is it affected by surface conditions? Is it less than the average depth of a submarine?
My guess, if the existing GPS stuff was adequate for their needs, they wouldn't be looking into doing this.
From the article:
Sounds to me like they don't rely on GPS at all, and quite likely because it's useless under water.
Lost at C:>. Found at C.
The writer doesn't understand what he is talking about.
If it's a magnetic compass, how could it be immune to interference?
Electromagnetic fields peter off very quickly, so while interference is certainly possible, you either have to be quite close or be able to produce an enormous sized field to be able to override the earth's magnetic field. Creating country-sized EM fields is to my knowledge not technology available to any military.
Then it's a "Global Positioning System"... GPS.
There is no doubt that it is a "global positioning system". It just isn't the "Global Positioning System".
About 3 inches. The GPS satellites transmit signals on two carrier frequencies. The L1 carrier is 1575.42 MHz and carries both the status message and a pseudo-random code for timing. The L2 carrier is 1227.60 MHz and is used for the more precise military data stream
Salt water attenuates 1.5ghz signals quite effectively.
Do not look at laser with remaining good eye.
Yes, but you'd have to know approximately where the submarine is before you can make a large magnetic disturbance nearby. Also, I would think that generating such a large magnetic disturbance would make you easy to find as well.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
Is It Really GPS If It Doesn't Use Satellites?
The answer is no. No it is not GPS If it doesn't use satellites. In fact, even if it does use satellites, it's not GPS unless it uses the data received by the USA DOD GPS satellite transmitters. GPS is a pronoun, a proper name. GPS refers to, specifically and explicitly, the DOD GPS satellite system and anything not relying on the signals transmitted by those specific satellites IS NOT GPS.
Satellite frequencies range from 1176.45 MHz for the L5 band to 1575.42 MHz for the L1 band, although it looks like only L1 and L2 (1227.60 MHz) are really used for the actual positioning. But then I saw a bunch of math I didn't understand, so I skipped to Wikipedia's Submarine Navigation page and it lists GPS as "Surface and Near-Surface", which is described as no more than periscope depth.
Could build the input stage with valves. It'll make your location sound better.
"These particles, stored in a vacuum, react to the Earth's magnetic field." Is it actually possible to store anything in a vacuum? If a vacuum is, by definition, a space that is devoid of matter, once you put something in it, it's not a vacuum anymore.
You only need a tiny disturbance. Drop magnetized microscopic chaff that stays aloft, or in solution...
“He’s not deformed, he’s just drunk!”
Salt water attenuates all radio quite effectively, except for VLF, which is cumbersome to work with.
Which, considering it is under water, is pretty impressive.
It's not like you can look out a window and pick a known target. It's more like being blindfolded in a vast space and trying to figure out where you're going with no other data.
Lost at C:>. Found at C.
Seems like it would be sensitive to magnetic interference despite the assertion.
Next up in our quest to solve the world's semantic quibbles: is it a metric system if it isn't SI?
Discuss among yourselves.
I am not a crackpot.
He's right! I'm sorry, I don't know which is wrong, if the isotope of Helium that is used for superfluidity is Helium 3 or something or if it is not so scarce.
My bad.
Not only is it useful, but it's secure too—the technology is apparently interference-proof.
Well, radio interference maybe.
Here's betting that a sufficiently powerful magnet or a honking great lump of iron in the wrong place would screw it up nicely.
In a survey of 100 programmers, 111111 thought that duck-typing was a good idea.
SINS = Ship's Inertial Navigation System, actually an old acronym.
Some mornings it's hardly worth chewing through the restraints to get out of bed.
How magnetic fields could be interference-proof ?
>> These particles, stored in a vacuum, react to the Earth's magnetic field.
>> Not only is it useful, but it's secure tooâ"
Lets just hope the bad guys never discover electromagnets.
Lame article, which points to a blog, which points to another blog, which points to the wrong place on a Russian site, which copied the article from The Daily Mail. The Daily Mail, even though a tabloid, has a halfway decent article.
I'm not going to explain inertial guidance; that's what Wikipedia is for. This is better inertial guidance. Here's a popular article which describes this new class of "gyros" and accelerometers. If you really want to know what's going on here, read Advances in Atomic Gyroscopes: A View from Inertial Navigation Applications
Laser "gyros", which work by interferometery and have no moving parts, have been around for decades. The best laser gyros still have more drift, by about 2 orders of magnitude, than the best mechanical gyros. Laser gyro technology has hit the limits of what you can do with photons. The idea here is to do interferometry with coupled atoms, rather than photons. That technology has been slowly improving for a decade or so, and it looks like it's getting close to deployment for high-end applcations.
One of the more interesting possibilities here is chip-scale gyros of moderate precision. Here's a Honewell patent from 2006 for one.
THIS JUST IN
Slashdot reader skims article and misunderstands new technology.
systemd is Roko's Basilisk.
It would still need to get close to the submarine, and the submarine would presumably still have inertial systems so it could detect when the magnetic sensor is being screwed with.
Don't take it from me - go get a compass and see how close you have to get with even a very strong rare earth magnet before it starts to effect the needle.
W..w..W - Willy Waterloo washes Warren Wiggins who is washing Waldo Woo.
The only article I could find that even vaguely attempts to explain how this works was, yuck, from the Daily Mail:
If trapped on a small device, like a trip [chip], their [the trapped atoms'] tiny fluctuations can then be tracked from great distances away and their locations pinpointed with a huge degree of accuracy.
Is that even remotely right? If these things allow subs and the like to be accurately located remotely, how does that make them impervious to interference, since presumably you'd then have to communicate the pinpointed location back to the sub?
What am I (or the Daily Mail) missing?
systemd is Roko's Basilisk.
...proposals (and lab prototypes / research) to use single atom trapping technology or atomic fountains or other such experiments to accurately measure the local gravitational field. The idea (and the source of grant funding, if you get my drift) was that If they did it at each end of a sub they could theoretically detect the faint effects of being near an undersea mountain. I think the most accurate version coupled two experiments together at each end of the sub which meant a vacuum tube running the length of the boat.
That was 15 years ago or more and I've no idea what became of the research.
Did i though? http://www.engadget.com/2014/0... Its nothing but a really bloody accurate accelerometer.
At the moment, the Ministry of Defense's prototype resembles a '1-meter long shoe box,' so the next step is to miniaturize it.
And is there a cat in the box? And how do they intend to miniaturize it.
The US government have made it clear that we have no inalienable rights; any we do not defend vigorously will be taken.
Sounds closer to inertial navigation than it does GPS. Also, doesn't magentic North shift around on a regular basis and doesn't the Earth's magnetic field fluctuate and is actually a little different in some places? How are they compensating for all this?
Are YOU using the TOOL, or is the TOOL using YOU? Think about it!
I always lose my GPS signal the moment I enter Canada. With international roaming off, I lose GPS as soon as I leave the US. That doesn't sound very satellite based. Does any GPS service use satellites these days?
a sub can afford a meter long shoebox if it provides precise positioning information... a smartphone can't obviously... but a sub can.
I've decided to stop wasting my time responding to AC trolls/sockpuppets... so if you want a response from me... login.
It's just a more accurate device for the guts of an Inertial Navigation system. .
As someone who works in the world of GIS, your smart phone probably doesn't use GPS using satellites either.
If you read the fine print they use something called "GPS assist".
Your cell phone talks to cell towers. The towers are in known positions (coordinates). If your phone can connect to several towers, it can send a signal to them and receive a signal. If you time stamp that signal and measure how long it took that signal to travel, you can calculate distance. You can then triangulate those lines into a interpolated coordinate of where you are. I guess technically speaking cell towers MAY have GPS to actuall talk to satellites, but it isn't like they are moving so why bother (once you have a known coordinate).
Back when the military used to fiddle with the accuracy all the time, people used to use known base station locations to correct their data. This is more less the same thing, except there is more, and you ditch the actual satellite signal.
Satellites work the same way. That is why you need multiple satellites on your horizon in order to get a fix. Not enough, and no location. Same with cell towers, go out of range, and no more GPS...
Since cell towers aren't exactly "global" like orbiting satellites, it could be more accuratly described as simply PS, or a Positioning System, or perhaps LPS, Local Positioning System....
Either way cell phones do not talk directly to satellites, and do not contain a GPS.
They DO however have advantages. GPS do need line of sight to receive GPS satellite signals. Block that, and no position. The most common being simple tree cover. Your cell phone does not have that restriction, only that cell towers be in range, which if you are in the middle of nowhere is a problem.
This has always made me wonder about car tracking devices. If you attach an actual GPS to the bottom of a car, it isn't going to get any signals, as the body of the car will block it (unless you run an antenna someplace). However a cell phone assisted GPS would just need the car to be around cell towers to operate. For all you tinfoil hat people, cell signals can be disrupted locally.... however it is probably illegal in most places.
Are you that stupid? The word sputnikovaya is russian for satellite... Sputnik 1 was the name of a russian satellite. fahrbot-bot was entirely on-point... Unlike you...ass...
FYI, while GPS specifically refers to the American implementation, the generic term for a GPS-type system is a Global Navigation Satellite System (GNSS). As a nationality-neutral term, it applies equally to GPS, GLONASS, Galileo, Beidou, and anything else satellite-based that might come along.
GALAKTOZ, or whatever the poxy Russian thing is called, is generally considered an alternative or rival to GPS, as is that faggoty thing the French want to build.
So I'd say that even if it's a System that tells your Position on the Globe then no, it isn't. Satellites or not is irrelevant. GPS means that particular system.
Confucius say, "Find worm in apple - bad. Find half a worm - worse."
The earth's magnetic field changes, and can flip..
http://www.pbs.org/wgbh/nova/e...
So I guess it just has essentially a map inside of it and "if the strength is so-and-so, we must be here"? So that data would theoretically have to be kept up to date? (The page above says a flip can take hundreds or thousands of years.. but still, seems like there would be fluctuation to make the reading not accurate.)
How do they obtain longitude? Do not tell me they observe the stars, as this is supposed to work in a submarine.
And I wonder how magnetic pole movements can introduce skews in the results
BTW, I recently learned that the GPS system began as a clever hack by JHU APL engineers, who determined the orbit of the original Russian Sputnik satellite by listening to its Doppler shift (this technique was recently used to locate flight MH370 by measuring the Doppler shift of its telemetry signal). After doing that, they realized that this calculation can be reversed: geographic coordinates could be obtained by lmeasuring signals from a constellation of satellites in known orbits.
The basic facility is plenty used in aircraft and ships alike, and its called INS (inertial navigation sensor).
It's just a different type of INS. Not to belittle it, its just that there is already a name for this.
Current INS systems run or Laser Ring Gyros, MEMs (microelectromechanical system), and there is also the old fashioned (and somewhat unreliable) old school mechanical INS systems (originally designed for submarines, to allow them to navigate for days underwater, without any access to celestial navigation or any electronical systems navigation too).
INS systems in general obtain accelerations and must integrate accelerations to obtain velocities and then integrate again to obtain position. This tends to make INS systems fairly inaccurate for long term positioning, GPS / Galileo / eLoran will always be needed.
The smart-ass answer is that it isn't GPS because the "S" as in "satellite" isn't used. The other issue is that the geomagnetic field is not stable, it changes rapidly over snort time scales, so how is it reliable enough to provide a stable grid? I don't get that.
On the other hand, go back a couple of decades and recall how surveyors made maps, and still do, incidentally. Geophysists measure tectonic strain in rocks by using lasers to measure distances between targets across active faults to milimeter tolerances. Not using satellites complicates that only a little, by requiring more control points on the geodesic grid. It is still possible to get order of magnitude accuracy without satellites. The satellites have reduced the cost to get wide area controls, so we are entering the phase where the satellite system is aging to fail and the replacement cost is high, so either we get back into the business of orbiting large things or we find the alternative.