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Global Positioning Without GPS
GadgetMike sends word of an award to Boeing for work on a Robust Positioning System that could make use of cell signals, television transmissions, and other clues to provide position information when GPS is unavailable. (Wonder if they've heard about Skyhook Wireless, which does a similar job based on Wi-Fi hotspots, for 2500 US cities and towns.) The work is being sponsored by the US military, so it's not surprising that they don't want to rely on upcoming GPS enhancers or replacements from France, China, and Russia. Here is the Boeing press release.
Reminds me of that near-field locater thingy they had in Aliens...
Hudson: This signal's weird...must be some interference or something. There's movement all over the place...
Hudson: Nine meters. Eight...!
Ripley: Can't be. That's inside the room!
Hudson: It's readin' right. Look!
Hicks: Well you're not reading it right!
Please mod me only (+) Underrated or (-) Troll
Pilots have used VOR http://en.wikipedia.org/wiki/VHF_omnidirectional_r ange for a long time. Knowing the lat/lon position of other radio beacons and being able to detect them is (IIRC) something that was experimented with for robotic vehicles.
Using geo-data and good state of the art receivers, it would be possible to locate your position reasonably accurately if you have many landmark transmitting beacons. The trouble is making those receivers small enough to be useful. Of course, this might not work too well in the middle of a desert but would function well enough for many problems.
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Alright, so let me see if I have this straight: If some other country tries to fire a missle at the United States, and we want to deprive them of accurate positioning, the United States would have to blow up a bunch of cell towers in the United States. Right?
My other car is a 1984 Nark Avenger.
Before the patent wars begin, there's prior art out here: I think it is called a "map" or something.
Robust navigation? From a jumble of tv/mobile signals? I don't think so. For absolute position VOR+DME is pretty good and ILS/MLS around terminal areas. Relative collision avoidance is handled by S-mode transponders and TCAS.
Use existing systems. ATC could gather all the TCAS negotiation information via the s-mode datalinks and use that to make a more accurate picture of the traffic than the survaillance radar alone can provide and broadcast that back to the planes. All that the planes really need anyway is their relative position to other planes more accurately. Absolute geographic position is accurate enough with the existing systems for purpose of terminal procedures and terrain avoidance.
Then again I think we should develop the reliability of GPS satellite constellation and adding Galileo to that will make it very robust with dual receivers and multiple antennas on the planes. To make ADS work will need dependable GPS type vector information anyway...
This is great, yesterdays technology for tomorrow. This is nothing more than an updated varient of LORAN.
We've had http://en.wikipedia.org/wiki/LORAN since WWII. It works fairly well for ships and airplanes, I'm sure it will be quite enough to guide airplanes to nearest aerodrome in case of aliens knocking off GPS satellites.
...it's called a map.
As for the rest of the Western world, I actually don't think most people do rely on GPS in any significant manner: most of their travel is to and from work and around town, in a place where they know the way. Modern civilian GPS systems, generally used for travel and trips and such, are as much used for their give-me-directions capabilities as they are for the you-are-here capabilities. If they stopped working, they'd be replaced by visits to Google Maps and such...
The World Wide Web is dying. Soon, we shall have only the Internet.
There are several answers. Sextants, LORAN, etc., but a big part of the answer is quite frankly "not know where the heck they were."
If you're going to be elitist, it would help to be elite.
They got lost. Ships hit rocks and aircraft hit mountains. Google Earth has an interesting feature where you can overlay old maps on the current images. There you can see how inaccurate the old map makers were.
From the military point of view, GPS means less bombs hitting civilians. During WWII and the Korea war it was normal to drop hundreds of bombs, flattening several city block or even entire villages, just to hit one bridge. Today when a bomb hits anything other than the intended target it's considered a major fuck-up.
The smarter technology gets around us, the more efficient we get. We need to make sure we have a fallback system in case the new technology fails, of course, but we are still much better off with the smarter systems than with the old tech solutions.
Well, the blackbird used astral navigation.
Yeah. Would you choose a neurosurgeon who pokes around people's brains in his spare time? I wouldn't.
Turn off all the radio transmitters. Turn off the lights. Don't give the enemy anything to aim at. Of course, the trouble is that, unlike the second world war, it's not going to be so easy to turn off all the transmitters. Just look at all the mobile devices out there radiating a signal. Even if you turn off all the telephone cells, all the cell phones will be out there looking for a pilot signal. Then there are all the cordless phones ...
How about not relying on things around you having power? For example, wouldn't the "enemy" want to take out your power grid? Wouldn't that then significantly change the picture from the signals around you? Heck, even WE could do that to ourselves if we needed to divert power to some military purpose and might have to turn off some civilian transmitters.
We recently saw some tech news (damn; can't remember where now) where two satellites in close tandem were making incredibly detailed gravity maps of the world and had shown how "sea level" actually varies by over 30 feet due to the gravity variance. Shouldn't we base a system on something like that (call it a Sci-Fi name to sell it: Gravimetric Locator Service - when it glitches its GLS for Get Lost System). Anyway, basing it on the gravity field would result in something that could not be changed over months during some type of war or anything. Just a thought.
And all this time I thought one only required a sextant and a way of reliably telling time.
You know, maybe not even then.
My car's navigation system still works even when I drive into a deep full concrete parking garage with many sub-levels. It shows my car moving around inside a sea of gray and never seems to lose track of where I am. I'm shocked by how bad hand-held GPS receivers are in comparison when inside buildings or tunnels.
So what's my car doing different?
I suspect the navigation system is cheating by using a look at the odometer and a compass to maintain position. I would think the error margin is much higher on this, but even after considerable weaving around in parking lots or tunnels there's no discernible position adjustment made when I re-surface much later. In fact, if I have the status indicator figured out, it's flying this way most of the time and only sanity checking GPS once a day, if that.
So why use GPS at all? Because probably the sum of hundreds of imperceivable slips or one big perceivable slip would totally b0rk your position until recalibrated.
Lots of businesses depend on GPS -- it's absolutely critical. i.e. trucking companies, Walmart, airliners, etc.
Use ping with several servers (you've got to know the physical location of the servers you're pinging) and triangulate the signal (well, OK, take more than 3 servers ;)
;)
Last I checked the Internet infrastructure was still obeying the law of physics and you still weren't getting a ping lower than 90 ms between, say, New York and Paris (as in Paris, capital of France).
It's not that precise, but it's not that bad either
Otherwise I'm fine with GPS, thanks.
This idea seems pretty flimsy..
If you are incorporating known, ground based beacons/signals to provide positioning data wouldn't it be easy enough for the enemy to emulate those beacons/signals from some location near to the real one to create multiple signatures and distort positioning data? Wouldn't this confuse the proposed system?
All it would require is transmitting eq that you could fit into a small, mobile (cargo van type) container. Now you have to a: track down the false signatures & have response teams to eliminate dupe signals, or b: rely solely on satellite signals which is what GPS does.
Am I making any sense?
Regards.
It doesn't need the compass, the steering position alone will do to propagate from a given location and direction. But a car moving on a dry and relatively flat pavement inside a garage or tunnel is different from a military truck moving hundreds of miles off-road, not to mention ships or aircraft which aren't touching anything solid.
The military do have one solution, inertial navigation, which has been reported to be accurate to something like a hundred meters after travelling ten thousand kilometers. But inertial navigation instruments are relatively expensive and not as accurate as GPS, they are used in submarines, where GPS isn't available, and in strategic bombers an nuclear missiles, where any external guidance system is presumed to be destroyed in case of nuclear war. Cruise missiles use still another system, they are guided by radar readings compared to a map of the terrain stored in their memory.
I suppose this system being developed by Boeing follows the military habit of developing several redundant systems at the same time. That's how the US federal government distributes what they grab in taxes.
I actually use it several times a year when I go backpacking, but I never count on it working and always keep USGS Topo maps and/or US Forest Service maps and a compass with me so that if my GPS unit fails I don't get lost. The GPS is nice to have in the back country, but more for purposes of tracking my pace, movements, and elevation than for actual navigation. The maps available for the back country tend to be off and are missing a large amount of information on trails so all that I can use in these cases is a the lat/long or UTM info (UTM works much better with Quad maps, but with other maps latitude and longitude work just fine). I think that anyone that really relies on GPS for navigation is just short changing themselves, not know how to read a map and figure out relatively close to where you are is taking a risk.
I am also a private pilot and spend a lot of time on the water. I have never counted on GPS in these situations either, although GPS sure is handy when it comes to getting right back on top of a known fishing spot. When I got my pilot's license GPS was not an approved form of navigation so we learned dead reconing skills and how to read a chart for VFR rules (who knows what they are teching new pilots these days, I haven't flown in a long time and haven't kept myself current). I never got my IFR license so didn't spend too much time with IFR tools like Loran but they can also be quite accurate. I know I could always find an AM radio station with the direction finder (I used it to listen to talk radio more then navigation, but it was fun to know where the stations tower was located). There are plenty of ways to navigate without GPS, most of them just require finding the intersection of two lines and having an idea of where you are in the first place.
I always imagined that the GPS network must be very vulnerable to attack, any nation as industrialized as say china could probabbly fill orbit with enough shrapnel bombs to destroy the bulk of the satellites around the planet if they put the resources into it. what did people do before GPS? Well theirs a few things, but most of them don't fit in your pocket. land navigation is extreamly difficult, I spent a good part of my child hood/early teens practiceing land navigation, and I wouldn't ever want to rely on it for anything that requires great precision or speed. Also celestial navigation relies on a unubstructed horizon and clear weather obviously. from the sounds of this system it seems fairly vulnerable to tampering and interference. I wonder if you could use sound freqencys transmitted through the earth to triangulate a position.
Sounds an awful lot like Intel's PlaceLab to me.
I read somewhere that you can use the stars as well for global positioning at night. That's an interesting and novel idea. Maybe they should do some more research on that.
-- Cheers!
Bullshit.
Planes flew before GPS and they somehow managed to arrive at their destinations.
Trucks deliver goods all the time.
Walmart employees might get lost going to the toilet, but thats not actually critical.
liqbase
Cellphone positionning does exists (and quite frankly I am tired of getting the same info over and over about Skyhook Wireless, which only covers Wifi positionning on laptop and not cell towers positionning and by the way has a very very high cost of functionning : ie paying a lot for wardrivers!). I would like to let you know about NAVIZON (http://www.navizon.com/) which does cell phones and wifi positionning systems since 2005 ! (Laptop and mobile devices) It is peer produced data and is available on symbian, windows mobile, Palm Treo, PC, and Blackberry!!. Oh I forgot to mention that it works internationnally their technology is not only for CDMA but GSM phones and of course any PC and mac.
Yes, but GPS has done a lot for alleviating the "highways in the sky." Without GPS, planes are not able to fly directly to their destination: they are restricted to flying along pre-defined routes between navigational beacons. Which by definition means that planes must fly closer together, which reduces the total number of planes that the infrastructure can support, not to mention making your flights slightly longer.
I do not know how overseas flights were handled. I assume they use longer-wavelength beacons, taking advantage of the vast expanse of non-urbanized surface below them, Compass bearings, inertial and celestial navigation. All of which are either more complicated (for the plane) and/or less accurate than GPS, and one of which requires an additional crewmember.
Can you be Even More Awesome?!
There are huge areas of Canada not covered by any cell or television signals. LORAN would be far more useful, though still not global.
GPS != Navigation.
The navigator is still a vital member of any crew (sea or air)
The craft still needs to be guided around storms and populated centres and away from trouble.
He has to locate and guide the pilot to the nearest base or strip in an emergency.
GPS does not instantly solve these kind of problems.
liqbase
This is really fascinating. I'm currently going through a course at Alteon to learn about the Boeing Business Jet, based on a 737. What really interested me during the avionics portion was how the Flight Management Computer calculated its present position based on multiple inputs, including GPS.
The way it worked was it took position data entered in by the pilot, position data from the Inertial Reference Units, and GPS. In addition, the FMC would tune into 3 VOR stations, and use the Distance Measurement Equipment ranges for those 3 nearby stations to triangulate its present position. The FMC would then caculate an average based on those 4, and use it for route calculations.
Ships would keep an active watch and log, they would triangulate their position against known landmarks, they would cross-check the ships log (odometer) with their bearing and known currents and record their estimated position on a regular basis until their could re-establish a new fix. Even when out at sea, ships would use a sextant, a clock set to GMT and the time of sunset/sunrise to give a fix to their long/lat. In fact all major commercial transport ships have to sextant on board and an captian who knows how to use it.
When sailing close to land, your exact long/lat position is less important as your relative position to things you can see. Having local knowledge of places to be careful is just as important as having a map.
GPS while very useful, and a great timesaver, but has made many sailors a bit lazy. In fact GPS has been responsible for some collisions. Some maps will include data gathered before GPS, a small island or rocky outcrop may have its absolute position slightly off. In the old days, this wouldn't be a problem, the sailor would make a note to visually sight it and sail around it. The GPS sailor may just look at a straight line on the map that skims past the island based only on GPS, which not be quite as safe in real life.
Also when sailing between two major ports, most ships will take a straight GPS line between them to sail. Thus the likelyhood of "traffic" is alot greater than a sailor who decides to sail a few miles off course and will likely not get close to any other ship.
When I was 12, the Boy Scouts taught me to triangulate my position with a map and a compass. Oh, and something to draw the lines with.
During WWII and the Korea war it was normal to drop hundreds of bombs, flattening several city block or even entire villages, just to hit one bridge. Today when a bomb hits anything other than the intended target it's considered a major fuck-up.
You mean like the cluster bombs and MOABs being used today? Don't fool yourself. The US might use smart bombs to accurately hit some things considered important. But they use plenty of terror weapons and other unnecessary bullshit, like depleted uranium projectiles, in civilian areas that fuck up civilians for decades to come.
When I worked for Philips Electronics in the 1980s, early 90s, they developed an in-car navigation system 100% based on odometry and compass. GPS didn't exist yet. The trick is that when a car makes a 90 degree turn to the right, for example, you know that it's doing that when there is a side street to the right. It is pretty unlikely that it will hammer the front of that office building :-). So, by combining the odometry/compass readings with mapping data, you're constantly able to re-calibrate your position.
I'm not sure if cars nowadays will use dual data-inputs (GPS plus some other navigation) for their navigation systems, because it would make it more expensive than simply relying on GPS. But the information is there to do it. The board computer probably even knows if the steering wheel is turned. You could fall back on that if you have no compass readings (I would guess a compass doesn't work well in a underground parking garage).
Browsers shouldn't have a back button!! It's all about going forward...
> "they don't want to rely on upcoming GPS enhancers or replacements from France, China, and Russia"
okay, i take issue with this one. By "Russia" they are talking abount GLONASS. and "China" they mean COMPASS.
Surely the dozens of EU countries working on GALILEO deserve just as equal a mention as France.
During WWII and the Korea war it was normal to drop hundreds of bombs, flattening several city block or even entire villages, just to hit one bridge.
It's truly amazing how bad navigational technology was during WWII. Bombers had trouble finding the right city. Early in the war, the Germans had trouble finding London. There were cases of aircraft landing in the wrong country. Looking up at the sky with a sextant was state of the art. Radio beams were tried by both sides, but were too easy to jam. Hits were either accidental or achieved by getting really close to the target.
I just use my sextant
It's good to see this going on.
GPS may not be around in times of war.
The Asian countries have ground based missiles that can blow up anything orbiting the earth.
This was just demonstrated a week or two weeks ago when they blew up a weather satellite.
An alternative navigation system needs to be up and running.
This was in fact a concern to the more paranoid in the 1950's or so, well, except with planes flying in to drop the bombs. There was in fact a system called Conelrad back then... In case it was suspected some Russians were trying to fly on in at night, the military or FCC or someone figured that they might navigate using radio stations as beacons. Conelrad was to tell all radio stations to go off the air. I have a 1959 ARRL handbook, and it has instructions for a Conelrad alarm that was to trip.. if whatever local station you tune the alarm to goes off the air, it turns off the "everything is fine" light, turns on a red light, starts buzzing, and cuts the wall current to the amateur radio the alarm is attached to. This was dropped a few years later, since any nuclear attack would have been via missiles rather than planes flying in and dropping nukes. But, in fact, if Conelrad had continued to this day, certainly cell phone towers *would* be rigged to drop off the ari.
Conelrad in the 1950s essentially did this with radios. The radio stations (AM I suppose, I don't know if there were any commercial FM stations yet) were supposed to go off the air in case of a Conelrad alert. People were supposed to shut off lights in case of a suspected attack, so the military or FCC or someone figured the aircraft may navigate using radio stations as beacons. This 1959 ARRL handbook I have has a Conelrad circuit people were supposed to add onto ham radios. It'd get tuned to a local radio station. In case the station goes off the air, it'd turn off an "everything's fine" light, turn on a red light, start buzzing and cut the AC power to the radio. Of course, with nuclear missiles flying planes in to drop nukes would be rather silly, so this was dropped in the early 1960s. But, if they'd decided to keep it, certainly cell sites would now be signalled to shut down. If cell phones do transmit with absence of a cell signal, I'm sure they'd be designed to never do it if Conelrad was still around.
"(I would guess a compass doesn't work well in a underground parking garage)."
*rolls eyes and shakes head*
I understand that very similar work has done by Hakan Lans in Sweden, however it was so good they would not grant him a patent ? Anyone know about this?
Oh come now, You must be referring to Galileo system that is being buid for the EU and ESA (European Space Agency) by European Satellite Navigation Industries. So it's basicly european system not French. Get your facts straight.
More on subject:
The EU site for the Galileo project http://ec.europa.eu/dgs/energy_transport/galileo/
The wikipedia site: http://en.wikipedia.org/wiki/Galileo_positioning_
MOABs are Cluster Bombs aren't used to take out bridges.
Cluster bombs are fantastic territory-denial weapons, and MOABs are great at clearing instant LZs.
Just not in cities.
There are four boxes used in defense of liberty: soap, ballot, jury, ammo. Use in that order.