Cheating has always existed, especially in our era of scientific and technological progress. Cheating methods are emerging in endlessly and becoming more and more sophisticated. Of course, we see more and more anti cheating work. In addition to the basic inspection of examiners, there are common devices such as metal detectors, mobile phone jammers and so on. Among them, signal shielding can be said to be the most brilliant means, especially in our era, with the continuous progress of electronic equipment, it can even escape detection. The current cheating means are basically that people in the examination room carry electronic equipment to speak questions and output them to the outside world, and then answer questions through people outside the examination room to achieve the purpose of cheating. These need to be transmitted through network signals, and signal shielding is particularly important at this time.

Suppose we treat these cheating electronic devices as a two-way radio, which plays in the examination room and receives outside the examination room, then the mobile phone jammer is an influence device that makes your radio sound inaudible. Our mobile phones, these electronic devices, need to communicate with other devices through the signal tower. Wireless communication requires electromagnetic waves. According to the characteristics of electromagnetic waves, electronic devices such as mobile phones need to be received within a certain frequency range, so mobile phone jammers affect the frequency of your electronic devices to make the frequencies of both sides different, so as to achieve the shielding effect.