It's the time of the annual college entrance examination again. The 2020 national college entrance examination will be held from July 7th to 9th. I wish good news to customers who have candidates! Because the high-power signal shielding device will be turned on at each test center during the test, it will affect the The wireless network quality of mobile phone users around the test center, such as: frequent inability to make or receive calls, intermittent calls, slow mobile Internet access, etc. After the exam is over, it will return to normal, please tell each other.
Although the time of this year's college entrance examination was affected by the epidemic and was postponed to July 7-8, in order to ensure the security of information in the examination room, the corresponding measures have not been reduced at all. Operators have issued announcements one after another. During the examination, the wireless signal jammer will be turned on according to the requirements of the Education Bureau, which will affect the communication quality of mobile phone users around the school. The communication will not return to normal until the end of the examination.
The principle of the college entrance examination blocker blocking mobile phone signals
The mobile phone signal jammer scans from the low frequency band of the forward channel (the channel from the signal tower to the mobile phone) to the high frequency band at a certain speed during the working process, causing interference in the process of receiving the message signal by the mobile phone, so that the mobile phone cannot detect the signal from the mobile phone. The normal data sent by the base station makes it impossible to establish a connection with the base station, showing a state of no signal and no service.
At present, the mobile phone signal blockers used in the examination room are all frequency bands, which can affect all frequency bands of 2G/3G/4G/5G of the three operators, and can also block all WIFI signals and Bluetooth signals.