GSM jammers have recently appeared on the automotive and telephone markets. These small jammer devices are used to encrypt and redirect the frequency of the waves emitted by electronic devices, so as not to interfere with some professions or achieve fewer available destinations. With different frequencies of interference, these antennas use the antenna to record and encrypt radio waves, which means they make them unreadable. Some GSM jammers have a long range, but the basic shielding distance does not exceed 40 meters.
"Today, criminals are using modern methods," prosecutor Brice Robin said in mid-April. He described the seizures related to the arrest of a team suspected and charged with assassination in 2014. In addition to classic police bracelets and beacons, investigators also found jammers and GPS beacons.
The jammer device overwhelms the signal from the mobile phone with a stronger signal. This type of device is equipped with several independent oscillators that send "interfering signals", thereby blocking the frequency used by the paging equipment and the frequency used by the control channel of the cellular / PCS system. When such devices are active in a particular area, they prevent (through RF jammer) all pagers and mobile phones in that area from receiving and sending calls.