When the mobile phone works, it is within a certain frequency range, the mobile phone and the base station are connected by radio waves, and the data and sound transmission are completed with a certain baud rate and modulation method. In view of this communication principle, the cell phone signal jammer scans from the low end frequency of the forward channel to the high end at a certain speed during the working process. This scanning speed can cause garbled interference in the message signal received by the mobile phone, and the mobile phone cannot detect the normal data sent from the base station, so that the mobile phone cannot establish a connection with the base station. The mobile phone is manifested as a search network, no signal, no service system and other phenomena.
Common mobile phone signal jammers on the market have operating frequencies: 869~894MHz; 825~960MHz; 1805~1880MHz and 1900~1990MHz, etc. The operating frequency bands are CDMA800, GSM900, DCS1800, and PCS1900. It can control the range of about 40 meters in diameter, using DC-DC converter input voltage and 5V output voltage.
The emergence of mobile phone signal jammers has played a certain role in suppressing the increasingly serious “mobile phone noise pollution”. But as a mobile communication interference device, will the electromagnetic radiation generated by the A topic of concern. At the same time, during the installation and use of mobile phone shielding equipment, due to the greater autonomy and randomness in terms of the number of installed units, transmission power, coverage, and radiation control, some places require effective interference and The shielding effect is maximized, even blindly introducing high-power mobile phones to interfere with the installation and use of shielding equipment. The impact and damage to the human body cannot but be worrying.
As another product of human beings, the “mobile phone signal jammer”, while shielding mobile phone signals and ensuring information security, it will definitely bring a certain negative impact. However, when we look at the problem, we should see the main contradiction. Just as we did not stop using a kitchen knife because it cuts vegetables, we will not reject a “mobile phone signal jammer” because it may cause harmful radiation to the human body. After all, the “mobile phone jammer” guarantees information security and contributes to social stability is its main contribution. The most important thing is that it brings security to places with high safety factors such as prisons, detention centers, and major conferences.
As far as the quality of the mobile phone signal shielding system is concerned, judging by the current level of scientific understanding, there is no security problem. The reason for this is mainly based on the following two reasons:
First, from a technical point of view, although the mobile phone signal shielding system is a new technology product, it should be said that it has been developed more mature in technology, so it has high security. According to the test report of the authoritative testing organization, the qualified mobile phone signal shielding system has low radiation, and because it is usually installed in high places, it has no adverse effects on human health.
Second, from a practical level, many authoritative units in China have begun to use mobile phone signal shielding systems. For example, in 2004, in order to maintain the solemn atmosphere of the memorial hall and meet its special confidentiality requirements, the Chairman Mao Memorial Hall Administration installed a mobile phone signal shielding system produced by Shanghai Jike Electronics Co., Ltd. in the memorial hall. After actual use and testing , The Memorial Hall Administration believes that the products produced by Jike Company meet its requirements in all aspects including safety and aesthetics. I think this should be a very convincing case. In addition, according to the information collected by the author, as a leader in the mobile phone signal shielding system industry, the products produced by Shanghai Jike Electronics Co., Ltd. are used in the prisons of the judicial departments and the detention centers of the public security departments. All of them are used, and the feedback after use is believed to be a proof of immortality.