Some areas requiring strict control, such as military sites, prisons and detention centers, are highly classified and should be strictly controlled. In areas such as military sites, prisons and detention centers, blocking cell phone signals can greatly prevent leaks.
In the information age, mobile phones seem to have become a necessity for life, and nowadays it is not uncommon for students to bring mobile phones to school. Although small and medium-sized schools around the world are not allowed to carry mobile phones while they are in school, the phenomenon has repeatedly been banned. In recent days, a high school in the provincial capital has been forced to turn off the lights in the evening and turn on the “high-tech” — mobile phone screening device. I didn’t think that the kind act attracted some parents’ complaints. One was that they were afraid that the screening instrument was not good for the students’ health, and the other was that they would lose contact in the middle of the night. The school was forced to stop using mobile phone shielding.
“The results indicate the potential for localized impact of this micro-cell phone jammer technology,” Williams said. “That is an encouraging sign that brings us closer to a solution that will make our communities safer and help prevent the continuation of criminal activity from inside prison walls.”
When the phone works, it is within a certain frequency range. The cell phone and the base station are connected by radio waves, and the data and sound transmission can be completed by certain baud rate and modulation mode. For this kind of communication principle, the mobile phone signal shield is at a certain speed in the working process to the high end of the channel to the high-end scanning. The scanning speed can be used to generate random interference in the receiver’s signal. The phone can’t detect the normal data from the base station, and the cell phone cannot be connected to the base station. Mobile phone performance is search network, no signal, no service system and other phenomena.
In order to prevent the cheating of examinees, it is necessary to use mobile phone signal shielding device and other technical means to block the signal in the examination room, so as to reach the requirement of mobile phone not being able to communicate and surf the Internet, which can also be a good way to prevent the masking of examinees.
The U.S. Air Force commenced the first of three Red Flag war games on Friday; aimed at providing a realistic approximation of combat operations against a peer or near-peer level opponent for U.S. and allied aircraft. Throughout Red Flag’s 42 year history, 28 nations have participated in the training event, with many more attending as observers. This year’s Red Flag training exercise, however, promises to be the largest ever conducted, and in an effort to increase the challenges faced by the combat pilots participating, Nellis Air Force Base is signal jammer access to GPS satellites, just as an enemy nation might do to hinder attacks from the air during war-time.