How Things Work: How Does a Cell Phone Find You?

How the cell phone revolution happened. The number of cell phones per person across the world and how that has changed over time. Density of cell phone towers across the world. A blown-up view of a cell phone. How a cell phone can find you anywhere across the world, explaining the terms: electronic serial number, SIM card, mobile identification number, system identification number (SID), control channel, registration request, and the mobile telecommunication switching office (MTSO). Why your phone has two numbers and why each number gets two frequencies. How you can be passed off from tower to tower. How the traffic app works on your phone to tell you where the heaviest traffic is, and a challenge to the listeners.

[@Bonno460xvr]

Hope your making millions off KZbin. Love your videos.

[@nathanhaiduk2957]

Your channel is a jewel, I don't understand why more people aren't subscribed .

[@travissmith2056]

This process explanation was entirely accurate. I would like to add, cell phones are classified as "emergency radios". The only mandated requirement, in the US, is the ability to connect to 911 services. Even on cell phones with no service connected, they still have & are required to be able to connect to 911. If it powers on, it will call 911. There are several "modes" of tracking or locating a "cell phone". The original or generic location services were based on what's called the "voice channel" of the device. This is the cellular connection from device to antenna which carries a voice call. This is the same channel or service used to send SMS (short message service) or text message. This was a system setup before internet was available to mobile devices. It was in the days of the original dial up internet. This became known as 2g (2nd generation) inet on mobile devices. Basically, it was dial up internet on a cell phone. FYI - a text is basically a "FAX" to a cell phone. This is when the basic "location service" was implemented, It wasn't very accurate as it used triangulation between towers. On old phones, if this service was, or even could be turned off, the device essentially was rendered useless. It was like "airplane mode" is today. This "locating" was done on the service providers end of the network. This was also before GPS chips were widely implemented. Now the locating services are far more accurate than before. Now GPS chips "triangulate" your location through the GPS system. The "work is done on the device itself. Now, the network doesn't "tell" where you are, the device triangulates from GPS satellite distance, figures out where it is & broadcasts this info back to network if connection is available. The traffic rates & patterns are calculated by averages. The device will update in real time with location & speed of device but this info is only "pinged" back to the mapping services periodically. If the device tried to maintain a continuous connection to the mapping service, the devices would become very hot & the battery would only last a few hours, at best. Essentially, now the devices location if calculated & recorded by the device itself & broadcasted periodically to the network service provider or mapping service or law enforcement. A specific location update can be requested from device if real time info is needed for legal reasons. Here's gome general info: en.wikipedia.org/wiki/Mobile_phone_tracking

[@antonmalyshenok1135]

Thanks for this explanation. So the question is then will carrier be able to detect my location precisely if I turn off location service on my phone? Or they would use old triangulation which will only work if I have 3 towers near by.

[@travissmith2056]

@@antonmalyshenok1135 This basic or general location svc is more of a govt. requirement. It is more like a emergency feature. You call 911 but the device is disconected, no carrier, the device will send it's location to 911. Almost like attaching a Long & Lat to caller ID. When you call 911, your device auto populates your loc. as best it can, for them. If you turn it off 911 can't find you. If you initate the call, it's assumed you are giving them permission to locate you. If you don't initate the call, it would require a warrent for them to recv personal info regarding your loc. Yes your carrier & location apps. will still track you but it would possibly take several hours to recv permission to access the location info. If it's off you call 911 & tell them you need help but don't know where you are, 911 will need to know your carrier, contact them, get a court order to access the dvcs location info from your carrier and then they can send help. With loc on, you call them, dvc sends loc. help arrives in minutes. Loc off, you call 911, they cross ref. device to know which dvc you are calling from then contact your carrier & have them find you. By the time they get to you, you're already beyond helping. You can't stop them from tracking you. As long as they keep this info nonspecific to dvc owner. The is what they are talking about when the say, metadata. As long as they don't specifically track you they can track everyone. Track all, ok. Singleing you out of the herd, warrant req. for your personal data. You don't want to be tracked, putting your dvc in a Faraday cage is your only option.

[@bofty]

This answered so many questions I thought I already knew, great videos!

[@jessethomas7949]

A couple years ago a friend of mine was on a road project where they had gathered for a meeting on site. It was no traffic in the area at that time of evening and with 10-15 people standing there it did show red on the traffic map.

[@johnd2058]

'Cuz they were just standing there. If they'd all started running, it would have gone green. 😉

[@jessethomas7949]

John D Maybe so. Lol

[@matbadeau8838]

111

[@ckliffames1]

If someone from the past was able to time travel to now these videos would be a perfect introduction to the world as it is today!

[@nicholasnafziger8998]

Illinois EnergyProf Delivers again - what a fantastic video!

[@StormGod29]

Not sure if any else wondered how you quickly search a list with 6 billion items in it but if the list is ordered, you can do a binary search which is insanely efficient. The list of phone numbers must be ordered for this to work but that isn't hard. You inspect the exact middle to see if your target is before or after the exact middle of the list. Discard whichever half your target isn't in and then compare again to the new middle. Shockingly it only takes 33 comparisons to either find your target or say it isn't in the list (2^33 = 8.59 billion).

[@charleythefarmer5008]

And since the items you are searching for are numbers, you can use the number itself to become the adress in memory(or hash) using a hash function, which might reduce the search time to only one operation.

[@supertom8552]

I’m a electronics technician and this blows my mind , thank you !

[@johnmurray7114]

Wow, this channel is so interesting and educational, a true gem! I‘m so glad i found it! :)

[@tota0523]

Ne mogu vjerovati da nema pozitivnog palca. Video je jako dobar i poučan

[@johno9507]

In Sydney, Australia my father had a 1971 Volvo that had rather rare (for the time) car phone installed. The handset was between the drivers seat and the door and had a rotary number dial. The rest of the system was in the boot (trunk) and was absolutely massive taking up a good 50% or more of the boot space. When he bought a new 1980 Volvo 264 GLE it had a new fangled push button handset and 'only' took up about 20% of the boot space. 😄 The whole novelty thing used to drive us nuts as dad would wait till we were all in the car to make mundane calls and so everyone outside could see him. 🙄 🇦🇺

[@jksharma7]

Thank you sir . you are a Wonderful Teacher with Great Knowledge .

[@silverstrings5569]

A lot of comments about tracking from the government, though there may be something to it. Information security should be paramount in such interactions, and it is something I think that you have glossed over in your explanation. That is to say,: Encryption is a very important step in that whole process. Otherwise, spot on, as expected.

[@willumwhitmore9419]

excellent

[@captainrobertcox]

Last year, I was working in a customer's back yard, when sheriff deputies came around the corner. When they saw no danger, they put away their guns and asked who called 911. My coworker realized he had "butt dialed" 911. I was amazed they had tracked the call, not to the house where we were working, but to the backyard of the house!

[@mjr1965]

Good video, but applicable only to CDMA technology. Should have discussed that the rest of the world outside of the US uses GSM (and now LTE)

[@rhyoliteaquacade]

I worked in a lab at Motorola in the late 70's , one day this guy comes in with a modified MX300 800 MHz radio and starts sweeping around our lab for interference. He spends a bit of time, then leaves. My boss is in awe, and asks me, do you know who he is? I say, no, my boss says that is Martin Cooper and he invented the cellular telephone. Years later, I realized the interference he was looking for was a test fixture I built to burn in a dozen 800 MHz monolithic power amplifiers. The power source was a free running oscillator.

[@inzinier100]

I am telecomunication engineer and you are awsome

[@wazza33racer]

the big breakthrough in phone communication was using packet transmission. Most of a conversation is silence ( no data) so that is not "sent" because it would tie up resources on a frequency channel. packets are also like UDP, which is if its lost, it does not re transmit. Previously there were dedicated circuits in phone systems that dedicated a chunk of bandwidth to each call and its massively inefficient and expensive way of sending data. This is only possible my moving from an old school analog system to fully digital.

[@Coalrollinfurry]

Think of a trunked radio system and replace the sites with cells. Aside from the data scheme it is a great place to start. Primarily in the uhf band.

[@brentonchattin]

This professor reminds me of Walter White when he's teaching in the flashbacks of Breaking Bad. My favourite channel right now

[@Jack__________]

Brenton Chattin I actually took Nuclear Engineering 101 with this professor back in 2001... he use to explode balloons of hydrogen to “wake people up,” but he really did it cuz it was fun and funny to him. He really is a great teacher!

[@420sakura1]

​@@Jack__________as long as he took safety precautions for the students. It's funny. If not, he's just an AH.

[@Jack__________]

@@420sakura1 there was no significant danger. He popped the balloons while standing near the chalkboard… not near anyone’s head. It was more so to wake up the class than an individual person.

[@tarjei99]

The experiment has been done with a wheelbarrow full of old mobile phones.

[@scottwilhelme9880]

Fun, but description made me think it was a discussion of tower triangulation to find lost travelers with cell phones, that would be more fun!

[@antonmalyshenok1135]

Well it could be that they definitely use some info from MTSO to show traffic, but it won't be that reliable. Because tower doesn't know your exact location, if you just walking you will probably be within one tower range for quite a while. But main data stream comes from your phone when you install google maps, or any other maps. Your phone just reports its GPS location to google/apple/etc server. You can try to disable it by stopping location service on your phone. In this case it would be much more interesting to do the suggested experiment as we can truly find out if google tracks us even when location service stopped.

[@liryan]

Yep. In his example the data is only known by google. But tower can force mobile to report measurements , GPS location is one of the data network can request mobiles to provide, so yeah, operators at best can know max 5m accuracy of a specific user.

[@u2dva]

Anton Malyshenok , Li Ryan, Mark OnTheBlueRidge - Have you ever heard of transmitter triangle principle? It can locate your cell phone in 5 meter accuracy :-)

[@KONAMAN100]

''iPhone 5s there's 6's out there and maybe by the time you see this they might be even better''. He didn't even dare guess the evolution and here we are just a few years later and it's iPhone 12+, I suppose 13 in testing. Amazing.

[@jesseestrada8914]

I just wanted to update, someone did his experiment. He had a bunch of cell phones in a wagon

[@duduong]

Just want to point out something rather funny: the map of cell phone coverage at 3:26 shows China with spotty service, but it is well known that China has half of the world's base stations.

[@stewartbridgforthiii5107]

Watching this on my iPhoneX

[@klausgartenstiel4586]

that cell tower tree is the ugliest tree i've ever seen 😂

[@Jason608]

Are you sure traffic detection is being done by cell phone signal detection? I thought they used GPS position data that your phone uploads on your data plan.

[@OldePhart]

Based on call quality of the modern era, I'm doubting the duplex nature of the connection. It was true in the analog days but now that everything is digital it is more like a collision based connection technique.

[@zalxder]

stick the SID in my brain and let's be telepathic

[@andraslibal]

The Congo is a rainforest like the Amazon

[@brentonchattin]

I was hoping he would mention The Congo

[@alexbrown1050]

Inaccurate. Traffic data for Google is obtained from Google Maps users over 4G data, not triangulated from fairly inaccurate cell towers.

[@justincase4812]

Sure has brought change. Not in good ways either.

[@MeaHeaR]

OMG é Power-Phull Orrrsé-Strâylêan

[@Jack__________]

At 15:16 it got creepy for me lol

[@IANinALTONA]

I doubt the traffic part. That's mostly since the majority of phones have gps now. The GPS data is tracked and used by Google .

[@u2dva]

Not everyone has GPS turned on on cell phone. It surely participate the equation, but it wouldn't be enough for precise measurement.

[@dauber1828]

Someone had done this with using a wagon and about 50 phones

[@paperburn]

yes it will look like a traffic jam.

[@TheShellshock67]

The experiment wont work... Google also checks the movement of the phone. Maps knows if i have been walking or been on a bicycle bevause itnlooks at the sensordata of how the phone moved

[@akta1984]

What about triangulation?

[@SimPilot7777]

Title should read "How Does a Gov using Cell Phone Find You"

[@420sakura1]

It's fascinating that you say this but at the same time fight for voter restrictions laws, government suppression of women's and minorities and LGBT people. You love the government only when it does their you like, traitor.

[@ajman031790]

This should be taught in highschool

[@maxheadrom3088]

The cell phone does not find me - it tells where I am.

[@sficlassic]

If I have my cell phone with me, can they give me a speeding ticket ?

[@travissmith2056]

Technically, your cell is considered your personal private property. Like your car they can't search it without a specific explanation of what is giving them probable cause & what they are specifically looking for in the search. In most cases there is a "in plain site" stipulation. Say the cop comes to your window & sees drug paraphernalia on the back seat. That's in plain sight & you can be charged & this gives "probable cause" to do a more detailed search. Nom if the paraphernalia is under something & can't be seen, you are under no obligation to move anything for the cop to see what's under it. There is also what's called the "scope" if search. This is dependent on what the are looking for, they can't just go on a fishing expedition looking for anything. Say they are looking for a person. They can't tear your car apart looking for a person. Could the missing person be in your glove box ot under you seat, no. They can not look there & say they were looking for a person under your seat. Now. if they find your baggie of whatever under the seat technically that would be considered an illegal search because the cop didn't have probable cause to look there regarding what they say they are looking for. Now we all know cops will make up a story, to justify their actions, after the fact. They can say, as I approached the car I could hear Mr.X on his phone telling someone about some crime & the info about this crime is in your phone. Bam, probable cause to search your phone. If he finds proof of criminal activity on it, it's admissible evidence. I it's laying on the dash he can say I say something on the display that gives cause to search device. Now we get back to scope of search. Looking for a stolen bicycle. Bicycle can't be in the glovebox, therefor that part of the car is out of scope in the investigation. They say, the dog alerted there were drugs in the car. The drugs could be in the glovebox. They look & there are no drugs but there is a stolen gun. Since the gun was found in a reasonable place to search for the drugs, the glovebox is now considered "in plain sight". Now we get to the phone. The phone is not a reasonable place to search for the drug investigation. But like I said the cop can just make something up to get your phone in his hands. "The phone looked like it had been tampered with & I wanted to make sure it was a real phone & not just a empty shell where your drugs are. As you see, he has manipulated the system to get your phone in his hands, under the "reasonable place to search". He has added the device to the scope of the investigation. He can now search the device. If he sees your porn or pics of you & girlfriend doing what you do. Hey, she looks underage, you are now being charged with child porn. He also sees an app., that shows an hour ago, you were racing someone, doing 115 MPH. He can now confiscate your device as evidence of your crime of 50 mph over posted speed. This is all because the cop found a way to include you phone in his BS investigation regarding something relevant to your speed. Now I'm sure a good lawyer could get the phone info thrown out of evidence but that costs money & time. Best advice, keep your phone locked in every way possible. This way when the cop looks for drugs inside the device, which he knows were never there, he can't just look at the phone & go, well it's unlocked, I have included it to the scope on my investigation & it's in my hands, I'm searching it. Back to the searching aspect. Dog does his thing by alerting on the trunk. They can ask but you don't have to unlock & open it. Remember the 5th amendment. The right not to incriminate yourself. The police will just grab your keys or call a locksmith or more likely, take a crowbar to it. Now apply this to your cell. He looks at it to make sure it's real & then asks you to unlock it so he can "complete his investigation". Like the trunk, you do not have to unlock it for them but in this case there is nobody they can call to break into it. You may have heard about the cases that have made the news about Apple declining to provide law enforcement with a way to get around users personal security on their devices. Apple also stated they would make it impossible even for them to break into their devices. That way if a judge somewhere tried to circumvent current laws & force Apple to get info of locked devices, they couldn't even do it. WoW, I just realised, have too much free time. Short answer, if police find evidence of a crime, yes they can use it against you. Keep your phone locked at all time during any police encounter, because if it's unlocked they will be attempted to find a way to go through it just to try to find something. Ever notice how if you get pulled over, as the cop walks up they always walk slow and the take a good long look in your back seat just to see if there's anything they can get you for.

[@IANinALTONA]

21:55 - it has been done: kzbin.info/www/bejne/fpOteIeBhpeBf6s

[@2014andBeyonD]

Always interesting to see on maps how small Africa is being depicted compared to Europe. In reality Africa is freakin' ginormous, dwarfing Europe. Like comparing a fly to an elephant.

[@johnplaid648]

Railroad tracks carry 5+ volts so you can power your cell phone by connecting charger terminals to both tracks, negative and positive.

[@user-adhenan]

😄😄😄

[@skyteus]

Say Cheeeeeeeeese

[@chrisinhotwater9896]

Well its 2023 and I phone 14 is out .

[@karolinasvobodova3265]

We should get videos like these instead of regular advertisements. I wonder how that could affect society.

[@Thomas-Designs]

iPhone 12 by the way🤣

[@TheRantingCabbie]

So could that traffic app tell you if ISIS is on the move and find them?

[@travissmith2056]

If they have a cell phone with them, yes.

[@wazza33racer]

and if you dont live in a metal box, the government can track and record everything you do.

[@u2dva]

Wrong. It can only know where you are at the moment.

[@wazza33racer]

@@u2dva if only..........Italian police were able to identify an entire CIA rendition team just from metadata harvested from cell towers following the abduction of a local muslim imam who was subsequently kidnapped by the CIA, taken to Egypt and tortured. Modern smart phones can have their camera and mikes activated remotely and record from there............then we have the hordes of CCTV cameras. Are you living under a rock or something?

[@u2dva]

@@wazza33racer Topic here are only the cell phones, not the other stuff like CCTVs. Talking about cell phone's mics and cams, to activate anything in the cell phone remotely it has to be allowed locally. If remote command doesn't find a local support script, it can do nothing. Are you James Bond or something? :-)

[@wazza33racer]

@@u2dva suggest you read up on SIM cards. They have embedded applets that can be coded to a do few more tricks than most people would know, there is even a redundant channel on the sim card physical interface to do point of sale. anything that has a SIM can be configured as a tracking bug. Its also why there has been a recent uproar about Huawei hardware getting into all the phone networks, it would give the chinese government a defacto spy network, instead of just being a US/Israeli spy network.

[@kenmohler4081]

But if you have three million people, each with a cell phone, how many government agents is it going to take to keep track of them all? The surveillance that everyone seems to be worried about is a practical impossibility.

[@jcman240]

Obama phones

[@oldi184]

Too bad flight from Europe to America takes 8 hours, just like in 1960s. Zero progress. If I could travel back in time to year 1960s and tell people that in year 2020 travel time from London to NY will take 8 hours nobody would believe me. I am sure people will make the trip faster. For 60 years they will invent better and faster ways. No sorry it will still take 8 hours 60 years from now. How sad is that? They can make smaller phones but they can't make faster air planes.

[@Hoppetassen]

oldi184 Of course they can make faster airplanes, or even rockets. Airplanes fly at the speed they do because its more economical, not because they´re not able to.

[@oldi184]

@@Hoppetassen Thanks but I find your answer unacceptable. So they cant make faster planes because it is not economical? How weird is that? New technology at the start is costly. But as time progress the same technology becomes cheaper. The problem is technology. Jet engine to be exact. We are using jet engine since 1949. How weird is that? Why we cant invent something better than jet engine? Something faster? Jet engine is at its limit. To fly faster we must fly higher and jet engine don't work in vacuum. Rockets on the other hand are still dangerous and even more primitive than jet engine because they explode still way too often. And their power cant be smoothly controlled like in jet engine where you smoothly add or remove thrust. Rocket just starts and goes at full speed till the fuel is out. Its quite primitive way. To fly faster we need new type of engine. Sadly there is nothing on the horizon. Every technology in the next 20 years is still based on jet engine. There are patents which shows better and faster ways of propulsion but for some reason they are locked in the box. Like for example force field engine patented in late 1980s.

[@mjb2048]

@@oldi184 Not weird. Aerodynamics and physics gets in the way. Engine improvements in efficiency required going a little slower. And, on a 6 hour flight you're about the same as the total time getting to and from the airport and going through customs, security etc.

[@oldi184]

@@mjb2048 You don't get it sir. Force field propulsion based on electro-magnetism is the way to move at hyper sonic speeds close to ground level. No loud sonic boom, no crushing sound from crossing the sound barrier is present. The air craft is flying in atmosphere but in fact is flying in a vacuum. Something like Supercavitation but not in water but atmosphere which is technically a fluid just like water. Air craft with force field engine can fly at mach 5 or faster in dense atmosphere and no sonic boom will be present. There are patents from 1980s and 1970s which talk about this device. Patents! Patent means finished technology which is ready. For some reason industry is not using these engines. Why? Instead we are still using jet engine which was patented in 1920s and 1930s. Why old technology is in use and new technology is locked in the box? It makes no sense. New technology is faster, safer, more efficient, cheaper. Why its not used? I know the answer. I think you know it too. Let me give you a hint. The answer is a 3 letter word. Do you know it?