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Ask Slashdot: How To Stay Ahead of Phone Tracking ?
An anonymous reader writes "In the last few years there has been a significant upsurge in subverting the cellular network for law enforcement purposes. Besides old school tapping, phones are have become the ideal informant: they can report a fairly accurate location and can be remotely turned into covert listening devices. This is often done without a warrant. How can I default the RF transmitter to off, be notified when the network is paging my IMSI and manually re-enable it (or not) if I opt to acknowledge the incoming call or SMS? How do I prevent GPS data from ever being gathered or sent ?"
As you know, they can track you even when the device is off, unless you've taken the battery out.
Turn your phone off when you aren't using it. Do you really have to be contactable 24/7? I suspect not for most people and if your phone is off then you cannot be tracked.
If you want to receive calls or SMSes, you need to leave the phone on and transmitting:
When a call for your number comes in, the incoming call is NOT transmitted nationally. Only in the GSM-cell that you are actually in is the signal transmitted. So, the system has to know in which cell you are to be able to "call" your phone. If you properly turn it off, the phone will tell the GSM network it is going off. So when a call comes in, it will go to voicemail immediately. If you yank the battery, the system will assume you are still in that cell where you last had the phone on, but it will probably time you out if it doesn't hear from your phone for a while. (which happens naturally if for example you drive out of range).
You can't.
Those are functions performed by the baseband software stack, which cannot be modified by the end user. Also you can't be simultaneously connected and not connected to the network anyway. If you don't want to be tracked by the network, don't use a cellphone.
Can't work. Your phone needs to periodically broadcast its location to the network, otherwise the network won't know which cell to route your calls to.
Great idea! Then not only are you giving away your location but you're transmitting your message in the clear, for anyone to eavesdrop on!
I can't help but think you've missed the point a little...
I suspect that's the answer you were looking for, but i'm afraid that's not an answer. Something like this would probably require hardware switches to be truly effective. It's much simpler to take out your battery as a few others have already stated. and dont forget to discharge the device by holding in the power key for a good 10-15 seconds.
I would say a good start is to just use the airplane mode of your phone. That should disable your RF transmitter. But of course you wont be notified when the network is paging your IMSI. The save option is to use a phone with OsmocomBB, a free software implementation of the GSM stack: http://bb.osmocom.org/trac/ It has limited functionality (no GPRS working at the moment) but at least you know exactly would your phone is doing. With that, you can even run CatcherCatcher, which is able to detect IMSI catchers: http://opensource.srlabs.de/projects/catcher The supported phones are a bit outdated, mostly old Motorola phones. But there is one supported smartphone: the Openmoko Freerunner. It is pretty usable these days and is fully supported by Debian. I love it, but you will need to tinker - a lot.
Thanks Apple, please tell your users how to remove the batteries!
As a ham operator VK4YEH, I appreciate this solution, but sadly, realistically it is not and will not be available to most people. OH well back to my ham shack .......
You missed this recent story: http://yro.slashdot.org/story/13/03/31/1755203/gauging-the-dangers-of-surveillance
The issue is that the government does not wait until they think you *are* a criminal to do this stuff, they start doing it when they think you *might* be a criminal, or worse yet, when someone *wants* you to be a criminal. It's not the stuff that would actually manage to fetch a warrant that a lot of people are worried about, it's the fishing expeditions that lazy crime fighting agencies and power abusing bureaucrats engage in if they don't like some of your associations. Just look to what happened during the McCarthy era to see what can happen when persons in power don't like the idea of you exercising your right to free association with people they don't like, regardless of if any rules are being broken.
There's no way you can be paged without being discovered. Paging is discovery. Silent paging is always possible. Even without paging, the phone needs to be registered to a cell.
So
Switch it off or throw it away.
aaaaaaa
- Buy it using a fake id. - Ask a homeless or drug addict to buy you a prepaid phone/sim and use it. - Buy it in another country.
The correct answer is live in a third world country Smart phones are about the only thing that will work reliably. After the electricity supply, security forces and tracking technology are the things least likely to work reliably
Sent from my ASR33 using ASCII
Stop using phones with GPS.
"If any question why we died, Tell them because our fathers lied."
Thanks Apple, please tell your users how to remove the batteries!
WIth a hammer.
Phone tracking was a result of the troubles in Ireland and the NATO/US need for Red trouble makers in 1980's Europe. ... your phone is sucking up details about your life as you walk around with/use it. :)
Think of an early Cyber Intelligence Sharing and Protection Act (CISPA) hardwired into every generation of phone by default.
Then came GPS, web 2.0, maps and cloud
Stop using your phone other than for family to say hi and ask for help/shopping.
Meet your people/tribe/business associates without a phone and talk face to face or in some other hi tech/no tech way.
Soon a working phone with CCTV (camera pod), facial recognition, 24/7 city wide look down drones, covert LEO in-car cameras will be filling in even more details.
Dont forget the private sector is also doing its part to link all their cameras in too
No warrants are needed. Deep extended boarder search, gang area 'random' searches, drink driving tests will all have rows of plate reading cameras, passenger face capture, driver logging, train station federal task forces, anti war mil protest watching... all add up to very deep efforts if you make a list.
All the tech used in 1950's Soviet watching, Vietnam, Iraq is now so cheap, tiny and sold to even the smallest, struggling police forces as federal 'gifts' to help with 'drugs', 'terror' or just as free 'surplus' with never ending private maintenance contracts.
The next big thing will be state level voice print records- no longer the play thing of GCHQ, NSA - expect a fake cell towers in a region of interest to do more than just log calls, numbers and record flagged people - your voice will soon be all that local law enforcement needs on any network.
Swap the phone sim all you want, better stay off the voice too.
Domestic spying is now "Benign Information Gathering"
So don't use your cell phone as a cell phone. Buy a pre-paid with no ID (if you can), use the data connection to open a VPN link, use whatever voice and IM protocols you want over the VPN link.
09F91102 no, 455FE104 nope, F190A1E8 uh-uh, 7A5F8A09 that's not it, C87294CE no. Ah! 452F6E403CDF10714E41DFAA257D313F.
This is rather disingenuous and attempting to rewrite history to serve an agenda. It's not "free association with people they don't like" when said people urge the overthrow of the U.S. government. Just look at other countries where the government WAS overthrown by the people that McCarthy opposed - China comes to mind.
Shutting down free speech with violence isn't fighting fascism. It IS fascism!
As stated you cannot turn off the transmitter and have the network be able to reach your phone. However you can get a smartphone with good custom rom and kernal support. Then you can build your own kernal and be sure it has a real gps switch. You may also be able to implement filtering of the network stack bit iirc, the radio section is often a binary blob. Find a phone where you can code all thos and you may have a popular product.
Silence is a state of mime.
Even with GPS disabled or if your phone doesn't have GPS, cell triangulation allows for a reasonably accurate position of the phone. In urban areas this works well, in rural areas less so but still enough to provide someone with potentially useful information. This is a function of the cell phone network and not the GPS of your phone.
Curiously enough I saw an idea to solve this problem this morning. It's a small bag lined with material opaque to radio waves (possibly lead foil or barium, I don't know). Whether this particular implementation works or is a tin-foil beanie, again I don't know. But the concept seems to me good. With modern phones like iPhones or my HTC One, the battery is non-removable, so it isn't easy for the user to verify that all radio transmission is in fact shut down - there could still be things like, for example, passive RFID. But if you had a radio-opaque bag in which you kept your phone, you could have a phone with you in case of emergencies, without the possibility of being tracked except when you were actively using it.
I'm old enough to remember when discussions on Slashdot were well informed.
http://www.schneier.com/blog/archives/2013/03/our_internet_su.html
But... if I were going to try and confound the system which can correlate almost all of your electronic records, you'd need to have a rolling list of sock-puppets who supply proxy identifying information to the cell towers. You'd need to have a bundle of SIM cards in the handset to do this, or to have electronics which fake the same data. Then, to make sure you can actually be contacted, you need to have a call redirection system sending you SIP calls (though if you're designing the hardware for this, you can encrypt the data streams carrying your voice over the existing cell transports - note that Skype may be encrypted but we don't know how well or who has a back door key). To avoid that being a single point of obfuscation failure, it probably needs to be a distributed network of TOR-like relays across hardware and cloud providers, and even then, it will probably need to be steganographically hidden in ordinary-looking traffic.
Not impossible, but still a pipe-dream since 1993.
For the REALLY paranoid geek I have a variant. There are lots of GSM modules that are intended for installation in some equipment. They need some power source, keyboard and microphone to operate. You may use something like the simplest PIC controller for keyboard and microphone control and be sure that unless you explicitly turn the microphone on it will be off.
It will still be a beacon, but you can invent some countermeasures, too. Your controller can detect the transmission and duly warn you if it finds something suspicious, for instance, long transmission without calls. If you are STILL overparanoid you may add a GPS device that will just turn the phone off while in zones where you don't want to be tracked.
Stationary GSM module with WiFi link to your real phone (or to your second secret GSM phone) is to be added according to taste.
I had a ham radio, but we ate it at Easter lunch. I don't know why my grandma insisted in carving the ham to look like a radio; but it was her house.
Memory is deceptive because it is colored by today's events. - Albert Einstein
I am in a position to offer a perfect solution. Just move to rural Australia and move your phone contract to Telstra. They are so fucking incompetent, nobody will ever succeed in tracking you.
:-/
The only downside is that you won't be able to make phone calls either.
Those are way too expensive
And then came the world.
Two points.
1 :) if the authorities waited until after you commit a crime then people complain that they should have stopped it. if the USA had definite proof of the September 11th attacks and knew who want where and when but the perpetrators hadn't committed an actual crime until they hijacked the planes, at what point should they have been stopped? after hijacking the planes? how about after they flew them into the buildings?
2:)Organizations that protest the government are generally the ones that might shift into violence and actually try it. You can't watch everyone all the time so you watch the ones that are most likely to do something. It is a relatively short jump from peaceful protest to full on riot. you already have the people in place, and have them angry about something. all you need is the right spark to set them off.
i thought once I was found, but it was only a dream.
That's what that battery is for - the mind control circuit. It's the only way they're keeping the people in line.
What most people don't know is that *that* is why there's a battery in your computer too! It has nothing to do with the stupid clock. The clock doesn't need the battery! You've seen the ones that work with a potato - that's proof enough that a clock doesn't need a battery. No, they have the computers programmed to reset your clock and bios after a short timeout to make you THINK you need that for the clock. And all you weak-minded losers fell for it, and the mind control circuit just keeps you believing that you need that battery.
Is it just my observation, or are there way too many stupid people in the world?
...when they just turned the border pink and we talked about... OMG Ponies!
Is it just my observation, or are there way too many stupid people in the world?
Dear Editors,
There is an 'Ask Slashdot' section for a reason. Please use it!
Thanks.
Fnord666
PS Putting "Ask Slashdot" in the title doesn't do it.
'The tyrant will always find pretext for his tyranny.' - Aesop's Fables
This is rather disingenuous and attempting to rewrite history to serve an agenda. It's not "free association with people they don't like" when said people urge the overthrow of the U.S. government. Just look at other countries where the government WAS overthrown by the people that McCarthy opposed - China comes to mind.
SERIOUSLY ??? The people that McCarthy chased were not the same people that were behind the cultural revolution in China, those were mainly chinese people.
There was never any measurable movement in the US to overthrow the government and establish a communist regime. Most people who were investigated under McCarthyism were only guilty of having opinions different from the average american.
Totally useful if you're more than say 50 miles from home.
If you're less than 50 miles from home, they know where you are anyway, and can triangulate your position.
Which autopatch are you suggesting that can answer a ringing line?
It's rather easy. All you have to do is leave your phone on the back seat of your car. If you want to go to the greater lengths, you might want to consider a trailer, or possibly a train.
Both ways. RF can't cross the cage either direction.
Before cell phones were cheap and everywhere, we had a large community of HAM operators who used our local 2m repeater to make short personal phone calls. It wasn't that hard to implement, just a DTMF decoder and a POTS interface board. We had improved capabilities once we replaced the repeater controller with a newer one that had this functionality built in. We were able to not only use DTMF tones to make phone calls, but to also patch into a network of linked 2m repeaters to converse with other HAMs throughout the state using VHF.
These comments are my own and do not necessarily reflect the views or opinions of my employer or colleagues...
This will vary by country, but in the US it is prohibited to transmit an encrypted message on the HAM or amateur bands. FCC rules, Sec. 97.113: " No amateur station shall transmit: ... messages encoded for the purpose of obscuring their meaning."
http://www.w5yi.org/page.php?id=121
Not even that. It varies by country, but generally there is a law requiring network operators to track anyone and everyone, and store the tracking information along with call and SMS records for a period ranging from six months to many years, so that if the government does have a reason to track you they can do it retroactively. Obviously something immensely useful to law enforcement (Pull the murder victim's phone records, discover his secret mistress), but still something that can potentially be very easily abused.
Seriously, if you're that paranoid about being traced, why even carry a cellphone?
Essentially, if you're going to turn off all the functions that allow connectivity, and disable the phone enough that you're *pretty sure* that you can't be traced, why are you even carrying it? It's going to be a non-functional pile of circuitry in your pocket, basically. If you're that concerned, then any time you turn it on you might be being traced, even if the radio function is allegedly "off".
I guess if you want to be able to call out in case of emergency, just buy a one-time phone and DON'T USE IT UNTIL YOU NEED TO. Then throw it away.
-Styopa
My solution is to stay a Sprint subscriber, that way I am never near any towers and if I see more than 2 bars I know the FBI is close.
load "$",8,1
The only really secure way to turn of a smartphone is to remove the battery. Get one where you can do that or mod it with a switch.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted by this and ignored otherwise.
As part of the new KGB-Plus service available as an option on many plans, the wireless provider can have genetically modified carrier pigeons enhanced with bloodhound DNA find and alert you anywhere in a growing number of metro areas. The specially-trained pigeons will carry a coded message that only you will understand to tell you to turn on your phone and prepare for an incoming call or text message, or to seek a safe house/shelter should your identity and location be discovered by unknown forces.
I believe that if your phone is on and in a frequency blocking bag, the battery will drain faster than normal, since the phone is now emiiting a more powerful signal trying to locate a tower.
We were able to not only use DTMF tones to make phone calls, but to also patch into a network of linked 2m repeaters to converse with other HAMs throughout the state using VHF.
Kids today wanna send text messages.
This is a complete quote from the relevant section of http://stallman.org/rms-lifestyle.html
Cellular Phones
I refuse to have a cell phone because they are tracking and surveillance devices. They all enable the phone system to record where the user goes, and many (perhaps all) can be remotely converted into listening devices.
In addition, most of them are computers with nonfree software installed. Even if they don't allow the user to replace the software, someone else can replace it remotely. Since the software can be changed, we cannot regard it as equivalent to a circuit. A machine that allows installation of software is a computer, and computers should run free software.
When I need to call someone, I ask someone nearby to let me make a call.
As a ham radio operator myself, reading some on GSM and other standards, a little on OpenBTS, and what the military (especially black ops like CIA) have done in these kinds of situations, I think I can reliably state this:
1. *ANY* radio transmission can be tracked to its source. If your phone on, it can be triangulated automagically by the base stations around you, although modern E-911 compliant ones also assist in this. In addition, the TIMING can be used to trace your distance from even one cell site (think latency/ping), so you can get a radius (similar to GPS, if I've read right).
2. The only way not to be tracked in this fashion is to turn off all radio transmitters on your person or nearby that can be associated with you. This includes wifi and can even include bluetooth in radio-quiet locations. Bear in mind you can fingerprint individual transmitters, to the point there are commercial transmitter fingerprint readers readily available: these are usually used when dealing with jammers, but you can track anyone with these.
3. None of this precludes them putting an active tracking device in your phone (I've read the battery can be replaced with a smaller one with a device included), your car, jacket, etc. These were being done during the cold war; the only difference is that you can buy them online now! And don't even get started on passive methods like lasers-on-the-windows, Van Eck, etc.
4. Jamming just keeps you from making calls: your radio can't hear the base. The base can still hear you just fine (under normal circumstances).
The bottom line: you'd have to do like RMS does and not carry one...though I wonder how useful that is since his entourage probably are loaded with them!
To work around all the problems the sibling posters pointed out, maybe just use a PC with a POTS interface and then connect the phone to that with IAX through an SSH tunnel. You'd have to bum off free wifi though and keep changing your mac address so you can't be tracked.
"When information is power, privacy is freedom" - Jah-Wren Ryel
Don't carry a cell phone with you unless you think you will actually need it. Leave it at home most of the time. Lend it to a friend to establish an alibi.
And when you are in a situation where you don't want to be tracked but still want the phone around in case of emergencies take the battery out. If you are handy with a soldering iron make an external kill switch. Also try experiments with a RF blocking bag to see what the effect on battery life is with your phone. Consider having spare batteries.
It wasn't that long ago when most people didn't have these devices. Really, they aren't particularly necessary for daily life.
Also put your EZPass transponder in the foil bag instead of leaving it on your dash all the time. Especially when you are doing something that you don't want coming out during divorce proceedings.
lazy crime fighting agencies
It's not just laziness - It's financial constraints. The US citizenry has made it clear to the government that there must be no taxes evernever (except when it comes to aircraft carriers and F-35s, then you can spend like a drunk sailor). You can't expect law enforcement to hire skilled investigators to run long programs but not fund them - So they're forced to take shortcuts.
Pagers are receive-only
True - But if you watch season 1 of "The Wire" (great show, BTW) you'll see a tale about how the police track dealers based on their patterns around pager usage.
if you have a phone. What would be really neato is if the people who make ROMs for Android phones could build in something that strips off location data or even allows ID spoofing.
For legal purposes, I think the police would have to prove that the phone was in your possession if they wanted to use tracking data against you in court, and likewise if you wanted to use it to defend yourself you'd have to prove you were in possession of the phone at the time the location data in question was generated. I don't know how easy that would be unless you were texting photos of yourself...
They wouldn't get your call records or contents but the location tracking would work just as before.
"When information is power, privacy is freedom" - Jah-Wren Ryel
US Patent 7751826 - Motorola submitted the patent in 2002, it was issued in 2010:
US Patent 7,751,826
The Federal Communications Commission (FCC) has mandated that, by December 2002, all cellular telephone carriers must market handsets capable of providing an emergency locator service. This emergency locator service, known as E911, will enable personnel at the public safety answering point (PSAP) to pinpoint the location of a cellular telephone user dialing 911. This FCC mandate further requires that the user not be able to override the emergency locator service in the case of a 911 emergency call.
This technology has raised public concern that, in addition to being used for emergency location, the locator service may be used by cellular carriers or by others to track the movements of cell phone users without their consent. There is therefore a need for a system that complies with the FCC mandate for location service while providing maximum privacy protection for cell phone users.
The invention overcoming these and other problems in the art relates in one regard to a system and method for selectively activating or deactivating E911 tracking service, in an embodiment by disabling power to GPS locator circuitry in a cellular telephone until the key sequence "9-1-1-Send" is detected. In one embodiment, the power to the GPS circuitry in a cellular handset may be activated by detection of a keypad sequence and the rotation of a physical switch to permit power delivery. When the handset detects the key sequence "9-1-1" it may output a signal that loads the switch into a "ready" position. When the user presses the "Send" button, the switch closes, enabling power to be delivered to the GPS circuitry. In other embodiments, the selective delivery of power may be controlled by software.
Motorola has been building phones for more than a decade in which the GPS circuitry is physically separated from electrical power until the user does something that causes it to be connected. This obviously doesn't help you if your phone has been hacked or modified and it doesn't help you avoid network triangulation, but it makes you wonder how all these supposed experts know all about the "dangers" of cell phones without having done much research or talking to the people who actually made the phones (you know, the inventors of patents are listed on the patents).
Example use cases:
And *poof*... you are off the grid.
- First they ignore you, then they laugh at you, then ???, then profit.
"Only One Way" is false. Putting the phone in a Faraday cage also works. Actually, just use a steel lunchbox.
It might also work if you wrap the phone in a couple sheets of aluminum foil, but I haven't tried that to confirm it. Just make sure that any external antenna doesn't tear through.
Put your phone in an aluminum foil pouch. (See Faraday cage) Take it out to check messages/make calls.
All you need is an empty potato chip bag.
-- My hovercraft is full of eels.
Not very useful. You don't need for the device to provide its location with GPS, the network can deduce it with no specific device support (except complying with the cellular standard for replying to the network pages and request for cells measurements). Google "RF pattern matching": it's 100% network side, and is more accurate than GPS in urban and semi-urban locations so cutting the GPS won't help at all here (and most people live in such environments nowadays). RF pattern matching is already deployed in some 2G/3G networks, and is currently being specified for future LTE evolutions.
In rural environments using the device GPS is still the most accurate method, but even then the network can provide a reasonable location estimation based on the device reporting the receive power of its serving and surrounding cells (a standard function, which is used to drive handover). And cellular networks do support this as not all devices have GPS.
When I went on the guy's computer I saw & ran the program.
by misrepresenting yourself as AC you have just violated the CFAA, a felony.
New Economic Perspectives
I wonder how feasible it would be to come up with a small field-strength indicator that at least lets you know if your phone is transmitting significant amounts of data when you don't expect it to. It's not too hard to construct such a device with older, modulated-carrier type radios, but it might be more difficult with a CDMA or other wide-spectrum device. Also it would be prone to false detection of other nearby cellphone radios. However I think it's your best bet for taming a commercial cell fone.
Then again it is easily thwarted by an app which stores compressed audio/location data on the fone and bulk uploads it whenever other traffic is occurring.
Measuring power draw of the battery might tell you if something is running when the phone is 'off'. It won't help you if the spying app is only active under normal operation, however.
As I'm sure many others have said, you could use pre-paid phones and recycle them every so often. Then again it may be pretty easy to identify you based solely on the people you call with that phone, along with other biometric information(voice indentification, for instance).
I think we're all going to have to get used to being tracked, scanned, inspected, detected and infected. What we should be doing is establishing a legal framework that offers us clear protections and a method of redress when our rights are violated. I think we're entering this new era blind - most Americans and even government officials can't even comprehend what's coming or what is already here.
We live in an age when most people don't have a clue why the bill of rights exists as it does, so the chances of success are not good.
http://www.masturbateforpeace.com/
Pro tip: Your point seems less false when you don't try to pass the same URL off as three different references. :-)
BTW, I attended Chris' presentation at DEFCON 18, and while he showed us all just how quickly so many of the phones in the room believed his fake tower, he never did demonstrate the actual interception of a phone call in front of the audience. I think the FCC and FBI were chilling his effect a bit that day. That said, I don't doubt for a minute that everything he discussed was entirely possible.
If you're really interested in seeing how far the concept can be taken, search Google for "Harris Stingray", and read a few of the news articles. Let's just say that Chris is not alone in his understanding of hacking the cellular protocols.
John
I wasn't tops in physics, but the lecture on Faraday cages really stuck with me - no ifs ands, or buts about how it completely separates the inside from outside electromagnetic worlds. So rather than running around pulling out batteries or modifying your phone, what's so hard about a metal phone case?
You may not need a tinfoil hat, but a tinfoil pouch may not be paranoid...
Instead of modifying your phone, turning it off, taking the battery out etc. you could build a mini Faraday cage. put the phone in there whenever it's not in use. :) When people ask about it tell them you've had issues with your phone running away.
Common Sense (+1)
After the electricity supply, security forces and tracking technology are the things least likely to work reliably
That strategy didn't work out so well for a lot of Taliban and Al Qaeda members.
I am becoming gerund, destroyer of verbs.
That feature is for power conservation not user security. Many such phones keep the GPS off until an emergency call is made to extend battery life.
For the paranoids out there there is a very real possibility of your phone receiving an "update" that hides the fact that your GPS is transmitting your location. And as the other poster stated, even without GPS, your location can still be approximated from your phones normal interactions with the local cell towers.
I am becoming gerund, destroyer of verbs.
Multiple tower triangulation, which seems so obvious, is quite difficult to implement, and is rarely done. Here's why:
- if you're fairly close to a tower, then other towers are unlikely to hear you. (This is by design: cell phone towers are designed to minimize overlap in coverage, so as to maximize frequency re-use over a geographic region)
- Those times when you are in range of multiple antennas (LTE people call these e-nodeBs), it's your cellphone that keeps track of the strengths of the neighboring e-nodeBs. This list of signal strengths and interference levels is not sent out from your cellphone unless a handover between enb's is about to happen.
- communications between a cellphone and a tower is not by a single carrier, but rather using a large number of discrete frequencies (for LTE, it's orthogonal frequency division multiplex). This type of modulation is designed to resist fading and interference, but is extremely difficult to triangulate, because the databits are spread over many symbols)
Most common localization of a cellphone uses a single tower. Simply knowing the antenna that you're connected through localizes you to a sector (of about 60 to 120 degrees in angle by about 1Km to 10Km in radius). The cellphone operator's Mobility Management Entity keeps track of this in real time, so as to route your calls, forward messages, and page your cellphone. Of course, this is several square kilometers, but it's possible to do much better:
Better single-tower geolocation takes advantage of every cellphone's being kept in tight time-synchronization with the clock in the tower's enb, using "Timing Advance". The Timing Advance method, in theory, can determine the distance of your cellphone to the tower within about 150 meters, but typically an operator gets 300 to 400 meters rms. This is a radial distance from the tower to your cellphone. The azimuthal location is coarsely determined by the sectorization of the tower: most cellphone towers have 3 to 6 enodeb antennas, and so can localize within 120 to 60 degrees in azimuth. And so, in general, you can be geolocated within an annulus: it's about 300 meters in radial distance from the tower, and about 60 to 120 degrees in azimuth. A fairly big territory: probably a football field or three. These systems are very useful for locating network problems, but cannot determine your location to better than a couple hundred meters.
A few systems can improve on this. For example, Newfield Wireless has developed a high resolution method of single-tower localization, apparently using enodeB timing data combined with local geographic information. But I'd be surprised if this results in better than 50 meter resolution.
Short version: Cellphone triangulation will not track you. Single tower tracking systems can yield coarse tracking.
This setup lets you always be able to dial out, but will eventually weary your friends who don't know what number you are now. You might want to do something else for a receiving number.
You probably have a core "fingerprint" of usage that is identifiably you, but it may resemble the fingerprint of people who run in your social circle. Mix things up a little. With each new phone add a new group of numbers unrelated to the other phones. Let's say phone #1 calls a cluster of sports related numbers, # 2 local civic groups, #3 bars, taxis, and liquor stores, etc. Call them a few times with honest questions. Let the watchers burn through their budget finding out who all these new d@#mn numbers are.
If your radio is off, it won't check in with the tower. If no tower has seen you, you won't be getting any SMS messages or voice calls.