Signal shielding equipment has been updating with the times. Now it can fully shield multiple mobile phone signal bands such as DCS, CDMA, WCDMA, WiFi, FDD, GSM, TD-SCDMA and TD-LTE. Mobile jammer, which can shield the signals of three operators of China Mobile, China Unicom and China Telecom and some other signals such as WiFi and Bluetooth, and shield the frequencies sent by the mobile phone receiving base station and wireless router through the interference frequency transmitted by itself, so as to realize the shielding of opponent signals.

In order to prevent students from taking classes carelessly, carrying mobile phones, secretly playing with mobile phones and affecting their study, some schools install mobile jammers in the classroom to minimize this situation. Of course, many friends may still remember that there was an incident in Hubei where examinees illegally brought their mobile phones into the examination room to take test papers and send them to the Internet to find answers. To this end, schools in some areas have also specifically aimed at this matter. The use of mobile jammers in the examination is also to avoid such incidents from happening again.