In order to ensure the fairness and justice of the examination and prevent cheating by using mobile phones, network jammers will be installed in the examination area for signal shielding during the college entrance examination. Although this will not only ensure a fair examination, but also bring some inconvenience to the lives of the surrounding people, after all, the college entrance examination is an important way for the country to select talents, and it is only once a year, so this unconventional method is adopted.

In the examination room, there are many occasions to use the network jammer. With it, it is difficult for mobile phones to transmit signals, which can prevent candidates from secretly using mobile phones to send messages. However, before using the network jammer, we should also pay attention to some mistakes:

① The network jammer will have different effective shielding ranges in different places of use. This is closely related to the signal field strength on site. Different models of mobile phones may not have the same shielding range at the same location, so it should be selected according to the actual situation before use.

② Factors affecting the shielding range of the network jammer include but are not limited to the distance from the base station, wall materials of the site buildings, installation height, installation specifications, etc.

③ During use, in order to avoid possible interference to some electronic equipment, a distance of 1 to 2 meters should be kept from common equipment.

Network interference can effectively shield signals and prevent signal transmission. When using the network jammer, we should know some mistakes in use, so that we can completely shield the signal within the maximum range.