Common mobile phone signal jammers on the market have operating frequencies of: 869~894MHz; 825~960MHz; 1805~1880MHz and 1900~1990MHz, etc. The applicable frequency bands are CDMA800, GSM900, DCS1800, and PCS1900. It can control a range of about 40 meters in diameter, using a DC-DC converter input voltage and 5V output voltage. After turning on the signal jammer, garbled interference is formed in the message signal received by the mobile phone. The mobile phone cannot detect the normal data sent from the base station, so that the mobile phone cannot establish a connection with the base station. Mobile phones show symptoms such as searching the network, no signal, and no service system. The signal sending and receiving functions of mobile phones within the specified range are invalid, and outgoing and incoming calls cannot be made, thus achieving the purpose of mandatory ban.
Principles of mobile communication
The working principle of mobile phones is as follows: within a certain frequency range, mobile phones and base stations are connected through radio waves, and data and sound transmission are completed with a certain baud rate and modulation method.
Principle of mobile phone signal jammer (shielding device)
According to the communication principle, the jammer scans from the low-end frequency of the forward channel to the high-end at a certain speed during operation. This scanning speed can cause garbled interference in the message signals received by the mobile phone. The mobile phone cannot detect normal data sent from the base station, making it impossible for the mobile phone to establish a connection with the base station. Mobile phones show symptoms such as searching the network, no signal, and no service system.
Basic functions of signal jammer
1. After the slow start function is powered on, the working power supply rises from zero to stable within 4 seconds.
2. After the shielding function is activated, mobile phones within the range will be blocked within 35 seconds.
Application scope of signal jammer
Various examination rooms, conference rooms, gas stations, oil depots, churches, hospitals, courts, military sites, libraries, theaters and other places.
