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Tracking People Via Cell Phone
An anonymous reader writes "According to the articleat the Guardian the UK Government have been working on a project to use the widely available mobile phone masts as a form of localised radar to track both people and vehicles without their knowledge.
Supposedly there is even work on the way to give this project the ability to see through walls!
Maybe Philip K. Dick was right to be paranoid about governments."
Take a look at here .
There you can give a permission to your friends with Sonera cellphone accounts to locate you.
I had the privilage of working for a mobile company in Ireland, and one day I was be-bopping around the building and accidently came across a room that I hadn't noticed before. I looked in and saw a giant metal cage and in the cage was a comuputer console and a couple of large servers. I asked the network guy later what it was and he told me it was for the Garda (Police in the Republic of Ireland) to be able to track people. Basically, under court order, they could track down anyone. The understanding of the technology has been around for a long time. Simple triangulation of transmission and there you go, got them. The problem is actually getting access to the information.
I found out later I wasn't supposed to know about that and that there were essentially Garda assigned to that room on a 24 hour basis to impliment any court ordered tracking.
Obviously you aren't made aware of these when signing your monthly agreement, are you?
D.O.U.O.S.V.A.V.V.M.
Normally I wouldn't reply to minor mistakes but that's modded up probably cause people don't really know how GSM works.
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> your cell phone has to announce it's availability to local cells
That's not technically correct.
You cell phone does not announce it's availability to local cells unless you are being paged (someone is trying to call you / sending you sms
The cellphone has to announce it's availabily to the new Local Area (UpdateLocation messages) when it enters a new Area but not to the cells when it is travelling between cells.
LAs cover usually several cities and can conver tens/hundreds of Kms square and you cannot be triangulated using that information.
However it is still possible for "them" to page you and drop the signal before your phones starts ringing so that your phone announces it's location to the cell and that way you can be traked...
Just so that things are clear
People seem to be imagining this technology giving you decent-quality moving pics of people moving around. Impossible (IMNSHO) for the following simple but adequate reasons:
1) Phone masts are designed for 1.8GHz tops. At that freq, lambda is about 17cm. Therefore that's about your spatial resolution. Also, this may not apply in all directions. You might, in fact probably will, be worse off in some axes. In fact, I'm not sure you'll get more than a 2-D map out of it, since cellphone masts are laid out in a 2-D pattern, and there is no "grid" in the third dimension (height above ground, altitude).
2) So, it's impossible to identify an individual with that poor resolution
3) And, you can;t even track one moving individual reliably. Someone would (IMNSHO) only have to approach someone, embrace them, spin around a bit, and alk off again, and then I suspect the "viewer" wouldn't be able to tell which individual was which. Do that a few times with a few people, and the number of possible people the "baddie" could be goes up rapidly!
4) All the above assumes the system works really well even at that poor resolution (17cm). What's the temporal resolution, or "frame rate" of the system? Pretty crap, I bet!
5) So quit worrying. There's no way that this technology can be as sexy as it sounds just using existing cellphone masts.
Martin "Fleetie"
"Absorbing your worst..."
To be very specific, it makes every mast into a Bistatic radar emitter. The tower emits the pulse thanks to GSM older design, and one or more reciever arrayed around receive the original signal and the bounces. So rather then allocate bandwidth, setup seperate emitters, and field it all over they are killing two bird with an existing stone.
This will see through some things, but not the way you think of it normally. You will get information indicating a "Large signal bounce", not the housewife at home. Although the low cost security, vehicle tracking, suspect finding (guns have a great cross section at these frequencies) applications are enormous.
Now the question is if they can make it work with CDMA. Possible, but probably not practical.
This really isn't that new of a technology. I know it has been proposed here in the US on some highways to use information like the number of cellphones in an area, the information could be used to track things like traffic congestion, and then monitoring centers could direct highway patrol to problem areas. It might also help alert highway patrol of accidents, etc. The idea is that they monitor the flow and can see the number of cellphones in an area. The technology of course makes sense because so many people have cellphones and with digital cellphone technology your phone maintains a constant, or almost constant connection to the cellphone tower to my understanding, whether you are making a phone call or not. I know that if you look at this http://money.tbo.com/money/MGAKCWDF15D.html that you can see where this sort of technology has already been used, but not applying to cellular phones. The idea is essentially the same however. I believe that the cellphone traffic technology stuff I'm talking about was planned for testing somewhere south of D.C. on the beltway or something. It was either Virginia or Maryland where I saw something about it though. Don't know if it ever got implemented.
:)
Some people may also know that reccent government mandates in the US have required cellphone companies and manufacturers to be able to locate a cellphone call to a more precise geographical area. I believe that the goal is something like 25 feet or so. I think the requirement is 300 feet right now. Not sure on this though. The reason stated was of course for 911 calls, however other uses could be conceived.
People can turn their cellphones off, however there are some theories that the phone may still give off some signals (so just remove the battery). Of course new legislation will require you not to remove the battery and the phone will not be able to be opened, etc or else you'll be brought to court under DMCA type laws! heheh Maybe going into areas of 'No Service' will be forbidden too
[Something witty and intelligent should have appeared here.]
{Traicovn}
The article talks of a radar system based on the reflected waves from mobile phones.
Like yourself maybe? ;) It is actually talking about using mobile phone *masts* as a basic radar station and has nothing to do with handsets what so ever. The reasoning is that since the base station's transmissions generate echos in the same way as a conventional RADAR installation's transmissions do, then you can listen to and make sense of those echos. By monitoring the returning echos at the base station you can generate a RADAR type map of the surrounding area, and by intelligently looking for changes within that you can detect say, a group of Greenpeace members approaching Sizewell B. nuclear powerstation as a moving state change from the normally static background image.
I used this example on purpose; if the system was live, and given the picture at the BBC this seems to be an ideal site (ie. flat, limited access) for this kind of thing. If the system were live already then these people would be in jail right now while someone tried to determine whether they are really from Greenpeace, or from Al Qaida. So the tinfoil hat crowd can relax for the time being. But here's a thought: Have you ever considered what an *excellent* RADAR repeater a tinfoil hat makes? Seriously.
Actually, the fact that any kind of intruders managed to get onto a nuclear installation apres 9/11 is considerably worrying to me, but that's another matter.
UNIX? They're not even circumcised! Savages!
Thank you for the clarification. I was concerned that since this was being implemented via. phone equipment, it would fall under that category. So, correct me if I am wrong again, a wire-tap concerns the information transfered only over the wire, but no metadata concerning the conversation, i.e. where and when it happened, possible videotaping of the conversation, sound amplification and recording on a party in the conversation, etc.? That can all be gathered freely?
If this is forging new legislative waters as well, I hope they do come up with something soon limiting the use of such systems without court approval. To me, it seems Video surveillance systems are easier to use without order to gather information and use against people, being that possession of the system that is recording you is 9/10ths of the law (Security Cameras, Traffic Cameras, X10 Cameras, etc.).
Zech Harvey, MCSE, MCDBA, CCNA
You're right. Law enforcement promises...Scout's honor...that they're not going to abuse this power. Fortunately, although we know they've abused every other technological advance, we're safe this time...because they PROMISE.
Or if we don't think we're safe, we're obviously terrorists, which makes it easier to justify monitoring us.
They're not just monitoring YOU, they're monitoring EVERYBODY. If that doesn't bother you, there are some pieces of literature I might suggest you read.
Why yes, I AM a rocket scientist!
One technique used in radar today is "pulse compression", that of modulating a radar pulse with a sequence that produces a large spike when correlated with itself. The most common such codes for actual pulses are called Barker codes, the longest of which is 13 bits. So, for example, with a 13-bit Barker code, a 13 microsecond "pulse" at 1 megawatt can produce nearly the same resolution and signal/noise performance as a 1 microsecond actual pulse at 13 megawatts.
There are also cyclic orthogonal codes that allow for even larger code lengths, turning a modulated CW signal into a virtual "pulsed" signal. Radio astronomers at Arecibo used this technique for radar imaging of Venus. The transmitter transmitted a megawatt or so CW, modulated with a sequence that was something on the order of 8000 bits long. The cyclic codes aren't as orthogonal to themselves as the Barker codes, but I believe they got an effective gain of around 5000-6000, giving an effective 5-6 gigawatt pulsed transmitter.
Note that CDMA happens to rely on orthogonal codes...
retrorocket.o not found, launch anyway?
Wrong.
I was a Ground Surveillance Systems Operator in the United States Army. Your right the resolution on the radar will not allow you to actually "see" the person, but It turns out you can "hear" the reflected doppler shift and a trained ear can descriminate between A vehicle, pedestrian or even two pedestrians if they have varying amounts of metal on them or have different walking rhythms. So If I had the opportunity to listen to a target walking, for about a minute, then the target embracing someone and walking off would do no good unless they had the same rhythm and the same equipment/belts/zippers and arm swing. I would be able to continue to track them. Of course if the target walked up to someone, embraced them and both targets then started skipping or prancing off in other directions, I would lose them, Or rather I would track both, so really this will only obfuscate you if you can walk up embrace, prance, and repeat. But doing this might draw attention to yourself.
This has been concieved as a way of defeating stealth aircraft, and some observers believe this was how the Serbs shot down the F117 stealth fighter during the Kosovo campaign.
Stealth aircraft work mostly by reflecting radar away from the transmitter. But when the transmitter and receiver are not located at the same site, this can be defeated. Mobile phone networks fill the air with electromagnetic radiation, and if any one transmitter is located at a "lucky" spot, the receiver will be able to pick up the reflection from an aircraft. Since the open air usually doesn't reflect any radiation, an aircraft will stand out from the background.
Of course, to aquire range information, you'd have to trangulate with another receiver. And you can hardly use the doppler effect to get rid of ground clutter, since you'll be listening to a wide range of frequencies from a number of base stations. Also, it puts a new perspective on the question of targeting civilian infrastructure or not.
Score:-1, Wrong
2) I don't believe that this system will be able to tell one person from another. So, for example, if you go somewhere where you can't be tracked (large building, subway, etc) the odds are that when you emerge you will just be an anonymous blob on the sceen (until you pass a security camera anyway).
3) Here's another idea. When walking about, keep passing very close to other people. It will make it more difficult for the operators to keep track of which blob is you.
4) Perhaps some sort of jammer could be devised. The total energy reflected by your body would be VERY small, so you would only need to radiate a microscopic amount of power. Probably less than would interfere with surrounding cellphones. Could a track on jam system be devised? Possibly, but I think that it would need changes to the central system.
Lockheed Martin's "Silent Sentry" system has been trackin airplanes this way for several years, but instead of using relatively weak and short-range cellphone signals, they use the immensely stronger broadcast television and radio signals. A simple demonstration of this technology can be done with any old TV attached to an antenna -- when an airplane flies over, you often get a distortion or echoes in the TV image. As you might imagine, if you explicitly start looking for these distortions, you can detect and track the airplanes remarkably well.
Lockheed's first installation had used regular Radio-Shack TV antennas, but they were replaced pretty quickly by simple T-shaped antennas, along the wall of their building near Baltimore-Washington International airport. They claimed to be able to track targets more than 100 miles away. One spectacular advantage of this kind of 'radar' is that it has no emissions of its own, so the pilots have no inkling that their plane is being tracked. Apparently these systems required substantial computing horsepower, but of course the price of that has plummeted recently. I'm sure that one could build one of these systems now for a shockingly small amount of money.
Given the work that has been done using the long-wavelength TV signals, I'm sure that it will not be long at all before the equivalent cell tower based system can be deployed. It will be interesting to see what it is used for. Theoretically, these systems could have tremendous positive value; for example, things like smart cruise-control that knows where all the cars around you might be. Still, at least in the beginning, you can be sure that it will be exploited by the military and police forces first.
thad
I love Mondays. On a Monday, anything is possible.
I have already pitched this idea to the South Carolina State Government to allow hurricane evacuation traffic management. During a recent evacuation, the Interstate was gridlocked for 24 hrs while a major highway 2 miles away was empty.
Moderation in All Things... Especially Moderation - gurutc
IIRC (can't find the exact article now), according to MilTech magazine, China has implemented, or is implementing, a similar scheme for military use. However, it is based on civilian TV broadcasts!
All these TV transmissions make up a radio pattern in the air, and by using arrays of passive receivers that analyze the radio waves at their particular spot, you can easily spot any large object moving through the air, interfering with the radio patterns. Thus, "stealth" aircraft will have a tough time as it is no longer necessary to return a radar signature to be spotted on radar -- you just have to be a large, blunt object in the enemy airspace.
So what enables this is basically lots and lots of processing power to continuously analyze the radio field patterns.