1.GSM on the use of intuitive features:
GSM system has several important features: good ability to copy security, network capacity, resource-rich mobile phone number, the call clear, strong stability are less vulnerable to interference, and sensitive information, talk less dead, low-power mobile phones.
2.GSM technical characteristics:
1. Spectrum efficiency. As a result of high-performance modulator, channel coding, intertwined, and a balanced speech coding technology, the system has a high spectral efficiency.
2. Capacity. As the transmission bandwidth for each channel, so that the same frequency reuse requirements than the plant stem down to 9dB, it is the GSM system with frequency reuse can be reduced to 4 / 12 or 3 / 9 and even smaller (simulation system for the 7 / 21 ); Plus semi-rate voice coding and the introduction of the Automatic Call Distribution handoff to reduce the number of times, so that the capacity of the GSM system efficiency (per MHz per channel of the small number) than the TACS system, three to five times higher.
3. The quality of voice. In view of the characteristics of digital transmission technology, as well as norms relating to the GSM air interface and voice encoding definition in the threshold above, the voice quality is always achieve the same level of quality has nothing to do with wireless transmission.
4.'s Open interface. GSM standard provided by the open interface, is not limited to air interface, and the press, as well as direct Internet network devices between the entities, such as the A interface and Abis interface.
5. Security. Through authentication, encryption and the use of TMSI number to reach safety. Authentication to verify the user's right to access. Encryption for the air interface, by the SIM card and network of key decision AUC. TMSI is a business network to the user specified in the provisional identification number in order to prevent leakage and to track their location.
6. With ISDN, PSTN interconnection, and so on. Interconnection with other networks generally use of the existing interface, such as ISUP or TUP, and so on.
7. In the SIM card based on roaming. Roaming is an important feature of mobile communication, it marked the user can automatically from one network to another network. GSM system can provide global roaming, of course, need to network operators between certain agreements, such as billing.
GSM system has several important features: good ability to copy security, network capacity, resource-rich mobile phone number, the call clear, strong stability are less vulnerable to interference, and sensitive information, talk less dead, low-power mobile phones.
2.GSM technical characteristics:
1. Spectrum efficiency. As a result of high-performance modulator, channel coding, intertwined, and a balanced speech coding technology, the system has a high spectral efficiency.
2. Capacity. As the transmission bandwidth for each channel, so that the same frequency reuse requirements than the plant stem down to 9dB, it is the GSM system with frequency reuse can be reduced to 4 / 12 or 3 / 9 and even smaller (simulation system for the 7 / 21 ); Plus semi-rate voice coding and the introduction of the Automatic Call Distribution handoff to reduce the number of times, so that the capacity of the GSM system efficiency (per MHz per channel of the small number) than the TACS system, three to five times higher.
3. The quality of voice. In view of the characteristics of digital transmission technology, as well as norms relating to the GSM air interface and voice encoding definition in the threshold above, the voice quality is always achieve the same level of quality has nothing to do with wireless transmission.
4.'s Open interface. GSM standard provided by the open interface, is not limited to air interface, and the press, as well as direct Internet network devices between the entities, such as the A interface and Abis interface.
5. Security. Through authentication, encryption and the use of TMSI number to reach safety. Authentication to verify the user's right to access. Encryption for the air interface, by the SIM card and network of key decision AUC. TMSI is a business network to the user specified in the provisional identification number in order to prevent leakage and to track their location.
6. With ISDN, PSTN interconnection, and so on. Interconnection with other networks generally use of the existing interface, such as ISUP or TUP, and so on.
7. In the SIM card based on roaming. Roaming is an important feature of mobile communication, it marked the user can automatically from one network to another network. GSM system can provide global roaming, of course, need to network operators between certain agreements, such as billing.
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