The essence of mobile phone jammer is to interfere with electromagnetic
The 2018 National College Entrance Examination will also be conducted from June 7th to 9th. According to the relevant regulations of the Ministry of Education and the Ministry of Industry and Information Technology, from now until the end of the college entrance examination, high-power mobile cell phone jammer will be turned on in the examination room, which will affect the calls of nearby users. As well as Internet perception, it will return to normal after the exam.
The following is to popularize the principle of signal shielding for college entrance examination:
The examination room in the information age is naturally indispensable with the addition of mobile phone jammers. With this instrument, it is almost impossible to rely on mobile phones. So what kind of instrument is it?
The principle of mobile phone (radio communication) is that within a certain frequency range, the mobile phone and the base station are connected by radio waves, and data and sound transmission are completed with a certain baud rate and modulation method.
In view of the above-mentioned communication principle, the mobile phone jammer scans from the low end frequency of the forward channel to the high end at a certain speed during the working process. This scanning speed can cause garbled interference in the message signal received by the mobile phone, and the mobile phone cannot detect the normal data sent from the base station, so that the mobile phone cannot establish a connection with the base station. The mobile phone is manifested as a search network, no signal, no service system and other phenomena. Mobile phone jammers are essentially electromagnetic interference to the wireless network, making the mobile phone unable to access the network and unable to receive signals from the mobile network and unable to send out information through the network.
At present, the development of wireless networks allows users to easily access the Internet and spread information through mobile phones. For example, in the college entrance examination and civil service examination, in order to prevent candidates from using mobile phones to surf the Internet, make calls, etc., the test center usually installs mobile phone jammers. Due to the lack of relevant regulations on the power size and installation location of the jammer, when the jammer is turned on in the examination room, other users around may also be affected by the jammer, causing problems such as dropped calls on mobile phones and unable to access the Internet.