Design And Implementation Of MSC SIMULATION Based On CDMA2000 1X

At the time of deployment and application of 3G network for each big operator in the world,3G r&d test is at its critical stage. The test results of 3G Network equipment largely influences the market belonging to each of equipment manufacturers. In order to testify the stability of base station controller (BSC) in Code Division Multiple Access 2000 (CDMA2000) system, a telephone traffic simulation system which simulates the chief functions of Mobile Switching Centre (MSC) which is convenient for test out of laboratory is needed to be developed. This topic is propounded in this situation.The method using combination of software and hardware to imitate the real equipment is adopted to simulate the chief functions of MSC. The MSC simulation system has been achieved by realizing signals flow specified in the A Interface standard protocol and Short Message protocol and Media stream loop back. The realized MSC simulation system can support Voice and Data and Short Message service. The interaction of Service signals is in strict accordance with standard protocols. The implemtion of media stream loop back is depended on the switch of calling and called timeslot on the DTB (Digital Trunk Board) board by the side of BSC. The simulation system can not support BSC to assign CIC (Circuit Identity Code) for calling. So, all the PCM (Pulse Code Modulation) used to transfer media stream should be matchd and connected before system running. In order to realize the media stream loop back, a software running on PC has been developed which can deliver real and simulation user number, configure PCM peers, map CI(Cell Identifier) and LAC(Location Area Code) and so on.Taking processing ability of board, call connection speed and large telephone traffic into account, HASH algorithm is adopted to quickly find, allocate or delete related resources for calling in this paper.The MSC simulation system has been used to test BSC of CDMA2000 without real Core network equipment. The test function includes finishing real phone, etc. Testing and operation results indicate that the system satisfies the need of BSS-Side debugging and testing.