In a certain frequency range, the mobile cell phone jammer connects the mobile phone with the base station through radio waves, and completes the transmission of data and sound through a certain baud rate and modulation method. When running, the rate sweeps to the high end of the channel at a certain speed. The functional properties of electromagnetic waves depend on their frequency. Mobile phones must emit electromagnetic waves that meet the requirements in order to connect to the base station of the communication operator. The screen and the phone emit the same radio frequencies.
Because the frequencies are the same, the phone can’t tell which signal is the base station signal in orbit, and the jamming is done. The interference frequency bands corresponding to the three signals are played repeatedly, covering three frequency bands at a time, but the time difference is not large, resulting in basically no talk time on the mobile phone.
A reporter from China Youth Daily contacted the operator’s technical staff. The person introduced that mobile phone signal jammers work by sending signals in specific electromagnetic wave frequency bands, which will interfere with the normal communication signals of mobile phones. In this event, candidates can upload pictures to the Internet from their mobile phones in the examination room.
Two situations cannot be ruled out: first, the candidate’s location is not within the effective distance covered by the mobile phone jammer; second, the affected frequency of the mobile phone jammer does not cover all the communication frequency bands used by all operators, and the candidate may connect to the mobile phone through a certain frequency band. the Internet. The person analyzed that if the mobile phone signal jammer used at the test site is designed for mainstream communication frequencies when it leaves the factory, and the new 5G network is not considered, the 5G signal may not be able to completely block the 5G signal. Already widely used, cell phone shielding devices need to keep up with the times. “