Research On Terminal Accessing Time Of Changchun CDMA Network

Code Division Multiple Access is a technology used in wireless communication. All the users of CDMA can use all the frequency bands at the same time, and the signals sent by other users are considered as interference. There is no collision at all. The advantages of CDMA are following: the voice quality given by speech coding technology of CDMA is better than GSM, all the noises can be decreased and make the talking clearer.The interference is reduced, the user capacity increases, and the transmit power is decreased by using spread spectrum communication technology of CDMA, with the result that the stand by time of terminal will be longer, what is more important, the harm to human sent by electromagnetic radiation can be decreased. The bandwidth of CDMA can be extended greatly, and images can be transmitted. As far as safety performance concerned, CDMA has excellent authentication system and the chance of eavesdropping is greatly reduced for its characteristics of transmission, that is, to distinguish users by coding. CDMA is developing rapidly, it is an important basic technology of IMT-200, and is one of standards of the third generation mobile communication system.The accessing time of terminal is one of the key indexes of evaluating user awareness. The paper is about terminal accessing time of Changchun CDMA Network. The average access delay of CDMA Network is 6.5 second now, but the access delay gets to 10 second in some areas. The users don't have the satisfaction, and they complain about it. The paper focuses on accessing time of CDMA Network, and summarizes the optimization method about accessing time. It is helpful to improve the whole network performance and user awareness.