Research On PN Optimization 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.With China Telecom 3G Certification being issued , changchun branch of China Telecom work to achieve "Net optimization and quality improvement" in accordance with China Telecom unified deployment. On the basis of the business development goal of this locality market and to prepare to network construction of developing customers, it is important to improve the operation ability and develop customers as soon as possible so that it can go ahead in the mobile communication market and achieve the goal of network business customers development. Now the business requirement has transformed from fixed-line business to mobile business and fixed-line business. It is of top priority for changchun branch of China Telecom that how to access seamless high bandwidth to infrastructure network with high-capacity and difference .First, This article narrates the background of local telecommunication CDMA wireless network and the need for PN replanning. With China Telecom 3G Certification being issued and on the basis of the business development goal of this locality market and to prepare to network construction of developing customers, it is important to improve the operation ability and develop customers as soon as possible so that it can go ahead in the mobile communication market and achieve the goal of network business customers development. With the rapid expansion of the size of the network, the PN planning of the current network cannot meet demand and restrict net development. To solve PN resource constraint, it is essential to make a plan.Second, it is significant to make principles and methods of PN planning by evaluating the wireless network of Changchun. After technical demonstration, it shall continue to make PN_INC=2 of PN planning and be divided into 171 PN for outdoor base stations, 54 PN for indoor base stations and reserve 15 PN of each. Through some experiments the planning shall deal with PN resource constrain , reduce a number of 2WAY of current net and promote network index.Finally, It sums up the practice effect of PN planning. It reveals after planning PN the comparison of DT test results in the urban and 1 X and DO test index are upgraded. It suggests that PN planning solves not only PN resource constrain, but also confusion of the current net PN and promote network index.