Introduction to GSM mobile phone and network
GSM mobile phone is what meaning: popular dot says GSM is a kind of network system, at present mobile unicom is GSM, telecommunication is cdma. Global System for Mobile Communications, the Global Mobile Communications System, commonly known as "gotone", is developed by Europe for the digital Mobile phone network standard, which is designed to allow users around the world to use a Mobile phone network standard to allow users to travel around the world using a Mobile phone. GSM system includes GSM 900:900MHz, GSM1800:1800MHz and GSM-1900 and 1900MHz.
GSM phones use GSM mobile phones. So far, cell phones have been made primarily of GSM, CDMA, and 3G, and so far, the phones have been in the first generation of analog cell phones (1 g), second generation GSM, TDMA, and the second generation of mobile phone technology, and 3G, and the 3G cellular technology of the third generation of mobile technology.
GSM: GSM: Global System For Mobile Communication network, also known as Global Mobile Communication System.
The frequency bands commonly used in Chinese mobile phones mainly include CDMA1X and 800MHZ band for CDMA mobile phones. GSM mobile phone occupied 900/1800/1900MHZ band; Nearly two years of GSM1X dual-mode occupation of 900/1800mhz band; 3G occupied 900/1800/1900/2100MHz band.
GSM system has several important features: anti-theft kao, large network capacity, better mobile number resources are rich, clear communication, strong stability, not easy to interference, less sensitive information, call dead Angle, mobile power consumption is low. Currently, the two major GSM systems in the world are GSM 900 and GSM1800, and because of the different frequencies, the applicable mobile phones are not the same. The former developed earlier and used more countries, the latter developing later and using fewer countries. In terms of physical characteristics, the former has low frequency spectrum, long wavelength and poor penetration, but the transmission distance is relatively distant, while the mobile phone has a strong transmission power and high power consumption, thus the standby time is shorter. The latter has a higher frequency spectrum, shorter wavelength and better penetration, but the distance of transmission is short, and the transmitting power of its mobile phone is smaller and the standby time is correspondingly longer.
Therefore, in the GSM network signal because of its several important characteristics, it is difficult to be disturbed in the communication aspect, generally in the area covered by the GSM network can normal communication. If the GSM network around you, and someone constantly call, harassment to you rest and work, do you want to interfere with his calls, it was almost difficult to achieve, if you use the general jammer, may effect is not very good. However, if you use a GSM jammer specifically for GSM signals, you can easily stop his phone calls and no noise from your cell phone. As one of the major pollution of the society nowadays, noise pollution is becoming more and more concerned by the society. The government departments of the state have strictly implemented corresponding measures against noise. There are also some people who don't obey, causing a certain noise disturbance to people's life, hence the presence of the GSM jammer.
The GSM digital cell phone is digitized before it is transmitted on a wireless channel. It is not as easily disturbed as analog mobile phones, so the voice is clear and small when it is spoken. However, because of the digital voice, there is also some distortion of voice. The phone's voice distortion is better than the GSM digital machine. Now, authorities are working on more advanced voice digital coding techniques to reduce voice distortion in GSM mobile phones.
CDMA digital network: CDMA is the Code Division Multiple Access, which is a new and mature wireless communication technology developed in the Division of digital technology. It can meet the high demand of the market for mobile communication capacity and quality. It has the characteristics of high frequency spectrum utilization, good voice quality, high confidentiality, low dropped voice rate, small electromagnetic radiation, large capacity and wide covering, etc., which can greatly reduce investment and reduce operating costs.
Industry operators are trying to increase the number of users in their systems, reduce the cost per user, create greater profits and actively strengthen market penetration. The code division multiple access technology is one of the digital communication technologies to solve this problem.
This article introduces you to GSM mobile phone and network related knowledge, so do you want to make a GSM jammer device? Here is the GSM jammer circuit for your mobile phone.
