how do mobile phones work?

[RobotNinja]

I have just sent a text message to someone who, for all I know could be anywhere in the country, the signal of that text must have been broadcast to the nearest mast, but then what? Is the signal then braodcast to every inch of the country in the hope of finding the phone or does the signal "know" where the phone is and If so does that mean someone can tell where you are any time you have your phone on you?

[Joanne-G]

Yes the text goes out to every mast or "cell" in the country and repeats the instruction for a period of 24- 48 hours untill the recipients phone receives it, and yes it is possible to know where you are in the country by your mobile phone. http://www.192.com do a service for �5 a month that will allow you to track a mobile phones location!

[wickedtart]

it find its recipient through signal masts which are located world wide. Also on some phone in messages they have a delivered box and this will tell u whether it has been delivered or not

[Ralph]

I don't think it does go to every mast in the country. I believe your phone logs on to the nearest base so the central computer knows where you are roughly. Sometimes you can hear the "de-de-de de-de-de" interference noises on your car radio as you drive along and your phone moves between base stations. Transmitting a message to every mast in the country would be tremendously inefficient. In fact, since I still get my messages in different countries, there has to be some selective broadcasting. If every message was sent internationally, we would all be cooked to medium-rare by tea time! They can find you with your phone. If you're logged onto two or more base stations at the same time (for the best signal for the phone) you can be located with alarming accuracy using radio direction finding. The people responsible for the Omagh bombing in Northern Ireland were convicted using mobile tracking information.

[craigyb85]

I think what happens is this: Your phone (when you buy/activate it) registers you on what is called a HLR - Home Locator Register (I think). All your details are stored there. The chances are it won't be anywhere near your home, but it's kinda random. When you switch your phone on, it connects to the nearest mast and your details are 'sent' from the HLR to your VLR (Variable Locator Register) - the place you want to use the phone. This is why, when you turn on your phone after it's been off for a long period of time, it can take a while to connect to a network. This is because your details have to be re-sent from your HLR. So, therefore, the networks know roughly where you are so don't need to send to everywhere!

[dec765]

Good Grief. It's a network! It knows where you are on the global network at any time. There are several tracking services available you can track the location of wife or kids mobiles. Same principle as IP