Cellular Phone Harrassment

Q: i have been harrassed with "anonymous"/"NO CALLER ID" cellular phone calls to my cellular number. i have contacted AT&T wireless and as well as contacting police station. none of them can help me. they told me the phone call is "un-trace-able" i would like to know if there is anyway i can find out who's been calling me to harrass me. this guy threatens my family's life and he called me over 50 times a day. at & t wireless told me that they can not trace the caller either. i am so so disappointed. my agenda is to: * help the police to put this guy in jail. please help or if you know anyone can help me.

A: Is it a GSM system? If it is, then the calls are traceable and the identity of the person can be revealed, through Call Detail Record or CDR. Whenever we make a phone

call, the subscriber identity is authenticated, and then it is used for Billing. Now, if he is a regular or a post-paid subscriber, it is very easy to trace him, either through CDR or via tapping the MSC links. But if he has bought a pre-paid card then it is difficult, since any one can buy this card, but normally the dealer who has sold this card to the subscriber should have his social security number or credit card number. So in reality a wireless subscriber can be traced. Normally, in other countries Police and Intelligence have easy access to the Billing information for Crime detection and Prevention. So i find it hard to believe that they cannot trace the guy.