Naked Science Forum
Non Life Sciences => Technology => Topic started by: @simpsonpg on 29/11/2011 04:01:01
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@simpsonpg asked the Naked Scientists:
@NakedScientists When someone phones my mobile, how dose it know where I am?
What do you think?
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Because your 'phone continually broadcasts it's identity and the cellular network knows which tower picked up that broadcast.
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When your mobile phone is on it transmits* a signal even when you are not making a call.
This signal, which identifies you, tells the network where you are.
[* every few minutes ]
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There are some service you need to activate or enter some number then you are able to know where your phone are.
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It is possible to triangulate an approximate position by noting signal strengths at more than one cell-site. This is not recorded routinely though and is not always reliable (you may only "see" one cell-site for example) but is a facility that can be invoked if required by security forces (for example). In fact there are quite a few systems available (and sold as separate software options) that the general public are unaware of, including things like remote phone tapping and recording.