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Mobile communication network basic by the mobile switching center (MSC), base station and control center (BSC), wireless base stations (BTS) and so on, its use fiber or DSL copper connection between each other, to provide business data transmission channel. Waves launched from the base station has always followed the mobile phone, when the user when the transition from one area to another area, mobile phones, automatically switching, that is to say, the phone is always in the "monitoring" of base station. Role to play in the transmit and receive signal transfer base stations, base station antenna is usually 9 root, points to three sectors, each sector three, three antennas have 2 root is the received signal, no radiation, only 1 root is transmitting. And to convert the data processing, the center is network operators in the middle of the room computer system, computer for the data processing, transmission and computing tasks such as expenses. Base station is always kept in touch with the system, the user's information timely feedback to the base station system, and the user at the same time in the business data to transmit data to the system, and then system for transit. Therefore, it is easy to find mobile phone users, base station, the relationship between the central computer system.
Mobile communication base station, because of the large target tends to make people to doubt of the environmental impact of base station electromagnetic radiation. Practice has proved, however, any period of mobile communication engineering construction scheme design, are considered. In terms of the country, there is a city of a communications tower near the top or no mobile communications tower, and hung above the microwave antenna, mobile communications, uhf antenna, etc., the corresponding engine rooms full of all kinds of modern communication equipment. However, from the national occupational disease prevention and control of various cancer incidence of a disease or the statistical distribution of the look, no signs of relatively concentrated in communication engineering and technical personnel. Therefore, there is no need to worry about electromagnetic radiation of base stations.
And, general mobile communication base station antenna height in 15 to 50 meters, electromagnetic wave propagation attenuation in the air soon. Tests have shown that the transmission power of 20 W high power stations, 10 meters before the antenna power density is 0.6 mu W/cm2, far lower than 40 mu W/c m2 national standards. Second, when electromagnetic wave through the general brick wall to about 6 db attenuation (four times), and through the wall with reinforced to about 20 db attenuation. As a result, the mobile communication base station antenna built when the house on the roof of the average house residents are absolutely safe.
In addition, our current standard (GB8702-88) 40 mu W/cm2 of electromagnetic radiation protection standards more strict than the industrialized countries in Europe and America, it is enough to prove that the country has electromagnetic radiation environmental protection is very responsible, and a complete set of equipment and technological parameters of the mobile operators are strict control according to the national standard.