The Importance of Signal Blockers in Ensuring Exam Security

In order to ensure the security of exam information, schools are implementing various measures. During exams, schools will activate Signal Blockers as required by the Education Bureau. However, this may cause a certain degree of communication disruption for mobile users near the school. To understand the role of Signal Blockers, it is important to first comprehend the working principle of mobile communication.

The Working Principle of Mobile Communication:

When using a mobile phone for communication, it must connect to a nearby base station in order to achieve normal communication. If during important exams, it is desired that mobile phones have no signal, it is not possible to deactivate the base stations near the exam venue. Otherwise, all communication devices in that area would be unable to function properly. Therefore, the only viable option is to employ Signal Blockers.

The Role of Signal Blockers:

Currently, the Signal Blockers used in exam venues can interfere with all frequency bands. To prevent the transmission of messages through mobile communication, these jammers transmit random interference, rendering mobile phones unable to detect the normal data transmitted by base stations. As a result, the phones are unable to connect to the base stations, and mobile devices within the interference zone will either display no signal or be out of service range, thus rendering them incapable of receiving or sending signals.

Furthermore, Signal Blockers not only interfere with the frequency bands of the three major mobile network operators (China Mobile, China Telecom, and China Unicom), but they can also disrupt Wi-Fi signals and Bluetooth connections.


In conclusion, the implementation of Signal Blockers in exam venues plays a crucial role in ensuring the security of exam information. By interfering with mobile communication signals, these jammers prevent the unauthorized use of mobile devices during exams. However, it is important to note that the use of Signal Blockers may cause temporary communication disruptions for mobile users in the vicinity of the school. Nonetheless, the benefits of maintaining exam integrity and preventing cheating outweigh the inconvenience caused by these disruptions. As technology continues to advance, it is imperative for educational institutions to adapt and employ effective measures to safeguard the integrity of exams.