Octavio who started this thread said

>. We want to jamm the cell phones inside
>the prision.

So we are talking about something that can be undertaken by the government
either openly or more likely covertly.

Gordon  said

>It seems to me that the Government or police in Brazil has the power to
tell
>the cell provider to disable or lockout cell traffic in a particular area.
>The cell provider could start locking out all cell phones active at a
>specific moment. Have the police not use there phones for a short period of
>time and start locking out users that become active until the police are
>confident of disabling most if not all of the cell phones in use by the
>prisoners.

Alxexandre said

>Octavio, this is a simple way to block it: Use a simple scanner to know
what >is the number of the cell that's inside of the prision. Do you have
the >number? Deactivate it at Telefonica!!!

Someone else mentioned the questionable performance of their
telecommunications ministry (sorry you got permanently deleted, not offence
intended)

From what I can see, the Brazilian Government appears to have adopted the
"He who pays sufficient money can do what he likes" approach. (This is not a
critisism as other countries have also adopted this approach). Which means
they have several (I believe 3) competing standards.

In my humble estimation

1.   Given the area to be covered having seen photographs of the prison

2.    Given that several incompatible standards are in operation

3.    A Government is involved

I would say that your best approach is for the government to legislate to
make the cellular phone operators provide the ability to "triangulate" calls
thus providing the ability to give a location. This can be done under the
reasonable guise of giving rapid response to 999 (Emergency) calls. Once you
have identified handsets operating in the area under survailance then you
have the option of monitoring the calls or cutting them off.

Regards
Chris

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