In today's information age, the development of communication technology is changing with each passing day. As a unique member of the communication family, mobile communication plays an important role in people's lives and industrial and agricultural production. Today, let’s talk about cell phone signal shielding in conference rooms. The principle of the device, secondly, while the mobile phone brings great convenience to people’s lives, it also has some problems that cannot be ignored. Due to the wide coverage of mobile communication networks, in some cases the emergence of the network, the use of mobile phones has brought people Trouble, even security risks, such as:
(1) Become a new leak channel, posing a threat to the security of confidential information;
(2) Become a new source of noise pollution, disrupting normal work order;
(3) Become a new unsafe factor and bring hidden dangers to enterprise safety production;
(4) It has become a new criminal method, which has an impact on social stability. Therefore, in some places, we should be able to artificially destroy or restrict this kind of network to avoid the harm caused by the mobile network. Under this premise, the mobile phone signal jammer in the meeting room came into being. The essence of the mobile phone signal jammer is: electromagnetic interference is implemented on the wireless network on which mobile phone communication depends, so that the mobile phone cannot access the network, and thus cannot receive information from the mobile network, and cannot send information through the network. But it has no effect on the signal generated by the mobile phone.
In order for the mobile phone signal jammer to effectively interfere with the mobile network, it must be ensured that the signal field strength of the jammer should be much greater than the field strength of the mobile signal BCH in the interference area. Therefore, the same jammer uses different locations and the effective area of interference. It is different. Generally, the closer to the base station, the stronger the local BCH field strength, and the smaller the area where the jammer reaches effective interference. Generally, the interference radius can only reach 0.5-9m; the farther away from the base station, the BCH field strength is relatively weak. Then the radius of the jammer to reach effective interference is larger, up to ten to tens of meters. Therefore, the local BCH field strength should be fully considered before using the interference device, and then the location, number and combination of the interference device should be determined according to the size of the interference area.
Obviously, the farther the jammer is from the base station, the weaker the field strength and the larger the interference radius, and vice versa. The jammer will lose its interference ability if it is very close to the base station.
The interference range of the same jammer used outdoors will be doubled compared to indoor interference. If the interference range is less than 200m, generally set a jammer, which can be hung on the indoor wall with a distance of 1~1.8m on the ground; if it is greater than 200m, generally Two or more units should be installed and placed on the front and back walls; if the interference space is outdoors and greater than 1000m, multiple units should be used, and the honeycomb distribution effect is better.
Since the frequency band used by mobile phones is dedicated, the transmission frequency of the mobile phone signal jammer in the conference room is completely within the mobile phone working frequency specified by the country, so it has no effect on other electronic equipment such as TVs and radios. At the same time, the mobile phone jammer only interferes with the BCH transmitted by the base station received by the mobile phone, so that the mobile phone cannot establish contact with the base station, so it has no effect on the mobile phone. Furthermore, although the signal field strength it emits is stronger than that of BCH, it is much weaker than the electromagnetic radiation field generated by mobile phone calls, so it will not cause harm to the human body. It can be used for a long time with confidence. Telecommunications focuses on the research and development of mobile phone signal amplifiers.