At present, the mobile phone signal jammers used in the examination room are all full frequency bands, which can interfere with all the frequency bands of the three operators 2G/3G/4G/5G, and WIFI signals and Bluetooth signals can also be shielded. The above is the principle of cell phone jammer. However, the frequency band of electromagnetic waves ranges from a few Hz to several hundreds of GHz, and each segment may be used as a communication signal. Will there be some special frequency bands that are used in the examination room? This is true for other radio communication tools, and radio communication tools with dedicated frequency bands “came into being” in this context.
In order for the mobile phone to effectively interfere with the mobile network, it must be ensured that the signal field strength of the jammer should be much greater than the field strength of the mobile signal BCH in the interference area. Therefore, the same jammer uses different locations and the effective area of interference. It is different. Generally, the closer to the base station, the stronger the local BCH field strength, and the smaller the area where the jammer reaches effective interference. Generally, the interference radius can only reach 0.5-9m; the farther away from the base station, the BCH field strength is relatively weak.
The wireless network facilitates people to access the Internet, but the problems caused by it cannot be ignored. This is not only a problem of accessing the network, but also a problem of network security. In order to maintain a good network environment, many places have installed wifi shields to prevent excessive use of the network. This equipment has been widely used in countries and regions around the world. Schools, prisons, libraries, reading rooms and gas stations are typical representatives.The benefits of home wifi mobile phone signal jammers are to ensure network security on the one hand, and on the other hand, it can also control the time that children use the Internet.