There are a variety of mobile communication system classification. For example, according to the nature of the signal can be divided into analog, digital; according to the modulation, can be divided into FM, PM, AM; by way of connecting multiple access points can be divided into:
Frequency division multiple access (FDMA), Time Division Multiple Access (TDMA), Code Division Multiple Access (CDMA).
Than the simulation of GSM mobile phones have great advantages, but in the spectrum efficiency of the simulator is only three times a limited capacity; in the voice quality is also very difficult to achieve the level of telephone cable; TDMA terminal access to the highest rate can only be achieved 9.6kbit / s; TDMA system with soft-switch function, and thus easy to dropped calls, the impact on the quality of service. Therefore, TDMA is not a modern cellular mobile communication the best wireless access, and CDMA multiple access technology for fully modern mobile communications network as required by high-capacity, high-quality, integrated services, such as soft switches, is being more and more Operators and users of all ages.
Frequency division multiple access (FDMA), Time Division Multiple Access (TDMA), Code Division Multiple Access (CDMA).
Than the simulation of GSM mobile phones have great advantages, but in the spectrum efficiency of the simulator is only three times a limited capacity; in the voice quality is also very difficult to achieve the level of telephone cable; TDMA terminal access to the highest rate can only be achieved 9.6kbit / s; TDMA system with soft-switch function, and thus easy to dropped calls, the impact on the quality of service. Therefore, TDMA is not a modern cellular mobile communication the best wireless access, and CDMA multiple access technology for fully modern mobile communications network as required by high-capacity, high-quality, integrated services, such as soft switches, is being more and more Operators and users of all ages.
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