What is a jamming device?

In fact, cell phone jammer is no longer a novelty in foreign countries and have been selling in China for nearly two years. Radio enthusiasts have even worked out a set of designs and published them on the Internet. The principle is very simple, which is like "talking loudly and talking quietly".

On the working principle of the equipment, there are such professional description: "the operation principle of the mobile phone is in a certain frequency range, mobile phone and base station connected by radio waves, in a certain way of baud rate and modulation complete data and voice transmission. For this communication principle, the cell phone mask is at a certain speed to the low end of the channel to the high-end scan. The speed of the scan can be used to signal interference in the receiver's message, so the phone can't detect the normal data from the base station, and it can't establish a connection with the base station.

Since it only interferes with the downlink signal, the device will not affect the mobile base station when applied, nor will it affect the normal use of other electronic devices.

Why need to jammer cell phone?

Today, smartphones have long been a staple of personal life, and in the student party, there are a number of mobile phone users. How to manage the balance between students' use of mobile phones, learning and entertainment... It seems to have been a difficult problem for parents and schools.

An official of the ministry of education of Massachusetts has proposed funded by the government in the student dormitory installed gsm jammer device, to avoid students at night after lights out by text chat, get to the Internet to affect the second day of learning.

Initially, the mobile phone mask belongs to a special equipment, which is suitable for special departments and special places. In recent years, mobile phone screening devices have started to be used in civilian production, and some schools have been used as a means of preventing cheating or being installed in public places such as oil stations, conference rooms, theatres and hospitals.

Mobile phone signal shielding device first appeared in the late last century, on the market at the time such products are sold to more oil and petrochemical enterprises, in order to avoid the phone switched on when the danger caused by spark. Later, it gradually turned to theaters, examination halls, libraries and other places that need to prevent cell phone interference and keep quiet.

Brazilian prisons have long been plagued by the clandestine use of mobile phones by prisoners. Now, a mobile phone jammer developed by Israel has helped. The device, which costs about 520,000 reais in Brazil, is similar in size to a laptop, with antennas and GPS positioning systems. If prisoners in prison, the use of mobile phones, mobile phone number, service providers and content of the SIM card and other information will be displayed on the instrument screen, not only mobile phone calls will be automatically cut off, prison authorities location can also lock the prisoner.