The reactive jammer system Prison-01 is built into prison cells in a tamper-proof way. The combination of detector and jammer send an alarm through the control system to the guards in case of illegal attempts of communication. This allows detecting means of communication such as mobile phones and radios. Thanks to the fast response time of the jammer it can be ensured at all times that there can be no unauthorized communication between the prison cells and to the outside world. With our technology the jammers are only switched on and activated, when there is an interfering signal or when a signal is deactivated. This ensures that jamming signals are not sent permanently.