"JoeSpareBedroom" <newstrash@frontiernet.net> wrote in message
news:iZL0m.6796$Uq5.3628@newsfe23.iad...
> "George" <george@nospam.invalid> wrote in message
> news:h201g9$irh$1@news.eternal-september.org...
>> JoeSpareBedroom wrote:
>>> My kid and two friends are going on a 3 week backpacking trip, and all
>>> their phones have a GPS feature. (My son's phone is a Samsung SCH-A950).
>>> Assuming the GPS feature has not been switched to "911 emergency only",
>>> and assuming the phone is in an active zone for the carrier in question,
>>> is it possible for the carrier to ping a phone and get an approximate
>>> location? I'm assuming no input from the phone user, other than the fact
>>> that the phone is turned ON.
>> Sure, no "ping" is involved. But do you have a question like "can I call
>> them and ask where juniors relative position is"?
>>
>> Law enforcement can but don't know if you can.
>>
>> VZW actually has a subscription product called "chaperone" for end users:
>>
>> http://products.vzw.com/index.aspx?id=fnd_chaperone
>
>
> Our idea is having law enforcement people track the phone. (TV cop shows
> often exaggerate the possibilities of technology).
>
> So, no "ping". Do cell phones regularly make brief contact with the
> nearest antenna, or something? And thanks for the Chaperone idea. Next on
> the reading list.

I was told that Chaperone tracking uses a tower triangulation method that is
more accurate than GPS if multiple towers are in range, and will wprl even
inside a building unlike GPS. True? Don't know.