Your Cellphone and the Police Stingray
The Stingray
Cellphones are handy devices. They make day-to-day living very easy. They also are an effective means for police officers to keep tabs on you. Understanding how a cell phone works can make all the difference in knowing if you are a person of interest. It can also help you disappear.
Cellphones are basically a two-way radio. It can send and receive information. They transmit on one of either two standards: GSM (Global System for Mobile) and CDMA (Code Division Multiple Access). Whether you are using one or the other depends on where you live. If you use Verizon towers, you are using CDMA. If AT&T, you are using GSM.
GSM Map
CDMA Map
More on GSM and CDMA here:
http://www.digitaltrends.com/mobile/cdma-vs-gsm-differences-explained/
http://www.hardcorpstravel.com/2011/07/how-to-use-cell-phone-while-traveling.html
Worth noting as 4G markets rise.
Your cellphone has two basic components, the phone itself and your SIM card. Both have identifiers that specifically ID who you are.
https://www.quora.com/What-is-the-difference-between-ICCID-IMSI-and-IMEI-numbers
When you power your cellphone on, it goes through a number of processes. One of those processes is to search for the strongest cell phone towers in the area. To save on energy, it targets the strongest one and keeps record of it. Every few minutes, your phone searches again to make sure it has a strong connection.
http://www.pongcase.com/blog/cell-phones-work/#sthash.6wwO33ky.dpbs
Ever sat your phone by a TV, baby monitor, or radio and your TV or radio makes a sort of static-like beeping noise for a few seconds? That's your phone communicating with the tower just to verify if it is still near the previous tower or needs to register to another, stronger one. The tower also takes note.
A tower can only hold so many callers in a given area. If you turn your phone off, the tower will know to drop you off the network. This frees up space. Not a big issue unless you live in a major metropolitan area.
What the Stingray will do is mimic a cell phone tower. They will amp it up until your phone catches it. Obviously this will draw other cellphones in the area, but they have the means to kick them back to the regular network while holding you on.
http://blogs.wsj.com/digits/2011/09/21/how-stingray-devices-work/
The problem with amping it up is that it forces your phone to constantly communicate. This is not something your phone normally does. Remember how it saves battery? So, as you can guess, this process can eat up your battery rather quickly.
A telltale sign.
One problem with the Stingray is that while it is holding onto your phone, your phone will not communicate on the regular network. If you are targeted for an extended period of time, and then returned to the network, you may get a bulk of missed calls, voicemails, and text messages.
Probably a clear sign as well.
Ever talk on your phone and it gets really warm against your ear? It does so because the battery is getting warm as your phone is constantly communicating to the tower as you gab away. What do you suppose might be happening if it is in your pocket and getting warm? If you've paid attention so far, you already know.
Damn, we're all screwed right? You can power your phone down, but who is to say that it can't be forced back on? I reckon if you pulled your battery out, nothing would happen. Your phone can't do anything without power. It's probably your safest bet if for whatever reason you think you may be targeted. If you're a leading anarchist, you may never know. But you might now...
