The working principle of the mobile phone signal blocker (also known as the cell phone jammer and the mobile phone signal amplifier) is: the scan signal generated by the sawtooth signal generator is inverted by the inverter, and then enters the voltage-controlled oscillator for code division multiple access, GSM It is modulated on the same frequency band as the three downlink frequencies of PHS. The modulated scan signal is amplified by the power amplifier. The power of the power amplifier is controlled by the voltage regulator tube to make the transmission power less than 1W. The amplified scan signal is transmitted in the form of radio waves. In the air.
Because the frequency sweeping signal forms random code interference in the message signal received by the mobile phone, the mobile phone cannot receive the normal data sent by the base station, which prevents the mobile phone from establishing a normal connection with the base station, thereby making the mobile phone separate from the base station communication network.
The characteristic of the mobile phone is to find a system with no signal and no service in the network to achieve the blocking effect, instead of relying on unlimited power increase to compete with the mobile phone base station to achieve the blocking effect. The electromagnetic signal strength from the mobile phone signal booster is very weak. As long as the electromagnetic radiation intensity of qualified products produced by regular manufacturers has been rigorously tested by national authoritative testing and certification agencies, the electromagnetic field intensity measured at all sampling points is lower than the "Electromagnetic Radiation Protection Regulations" stipulated by the State Environmental Protection Administration.
It will not cause harm to the human body, so there is no need to panic. The unnecessary psychological burden is the real obstacle. The power of the mobile phone signal booster is very small (≤1W), and the range is only 20-30 meters, which will not cause any damage to the mobile phone base station. interference. In addition, when applied to specific situations, it is impossible to talk about endangering public information security.
The frequency of the electromagnetic signal emitted by the mobile phone is completely within the working frequency band of the mobile phone stipulated by the country, and the signal is always in a relatively static and constant state, and will not affect any other electronic equipment, will not interfere with the human brain, or affect normal human thinking.
