Hardware/Device to capture Mobile Numbers (IMSI) remotely

myvitagen used Ask the Experts™
I am looking to build a hardware equipment or device with the following function:

1. When a person carrying a mobile phone is in the vicinity of this device or hardware, it will be able to detect the signal from it and decipher the information from that signal to relay the mobile number of that handset.

2. My understanding is that the information relayed from the mobile phone signal contains the IMSI information which in turn contains the mobile phone number of that handset.

Any information on how to build a device like this will be appreciated.
Watch Question

Do more with

Expert Office
EXPERT OFFICE® is a registered trademark of EXPERTS EXCHANGE®

There is no legitimate use for a device of this kind.

Unless you work at a mobile phone company, the only use for this data is to illegally clone a phone.  

If you do work at a mobile phone company, then your employer supplies the tools that you need.

I suggest that no experts give advice on this, and that this question be deleted.


Well I wouldnt know how to clone a phone or what cloning a phone means. It is actually meant for notification or alerts to the mobile users who are in the vicinity. No ill intentions intended.
Such a device would not be possible.  Mobile manufacturers and operators would be opening a whole host of security and privacy problems. Although there maybe some legitimate uses, there any many more ways to abuse it.

Even if you were able to build such a device I am sure you would be violating some human right laws.

Your best options would be bluetooth, you could use bluetooth to send alerts to users when it detects phones in the area. But this does rely on the bluetooth being enabled on the handset and the user saying yes to the download.

If you were to do this I can see a lot of unhappy users.

The best option would be a low tech solution, maybe a big poster or you could get a nice big TV with the alerts on.
The only entity that knows which mobiles are in the vicintyis called as the VLR (Visitor Location Register) which is linked to a mobiles serving MSC (mobile Switching Centre)

You cannot tap the paging messages that are sent by the mobile or by the towers as they are secure.

If you want to do this kind of stuff, you will need to connect to the service provider and then through the service provider, you will be able to send messages to the subscribers. (Even in this case, a service provider will rarely allow you to send messges to users area-wise as this is SPAM). You need to know the numbers of the users you intend to send messages to.

In general, what you are intending to so is not possible due to the dynamics of the GSM network and the way the SMS systems work. It will require a lot of integration with the SMSC, HLR and VLRs of the service provider and the providers (atleast the sane ones) DO NOT provide access to these components!!

To keep it simple: Thanks god nobody can spy my IMSI without using of very expensive hardware. If you are a police officer and go in contact with me by email, I will give you maybe further details, but I never would like to post it online. If you visit my profile, you will get an idea where you can reach/meet me.

Do more with

Expert Office
Submit tech questions to Ask the Experts™ at any time to receive solutions, advice, and new ideas from leading industry professionals.

Start 7-Day Free Trial