The major difference between CDAM and GSM

The major difference between CDAM and GSM
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CDMA is the abbreviation of CDMA (Code Division Multiple Access), it is in the digital technology branch of spread spectrum communication technology, developed on a new and mature wireless communication technology. CDMA technology is based on the principle of spread spectrum technology, will need to transmit signal bandwidth has certain information data, with a bandwidth far outweigh the signal bandwidth of high-speed pseudo-random code for modulation, the original data signal bandwidth be expanded, then the carrier modulation and send out. The receiving end use exactly the same pseudo-random code, and receive the bandwidth of the signal for relevant processing, the broadband signal into the original information data of narrowband signal that is expanding solution, in order to realize information communication.
GSM is Global System for Mobile Communications of the abbreviations, meaning the Global System for Mobile Communications, one of the world's leading one of the cellular System. GSM ?