Soft Switching Of The Cdma System And A Number Of Issues

In currently CDMA (Code Division Multiple Access) system, "capability" is called a "soft" capability, handoff is called "soft" handoff, overlay is called "soft" overlay. These concepts are not in accord with the concepts in the GSM system. The soft handoff and the capability have been catching the people's attention in the CDMA communication system. The CDMA communication's capability is much higher than the GSM communication system. The capacity of the system is limited by the interference, so the CDMA system's capability is decided by many factors, in which soft handoff is one of the key ones. So analysis the relationship between soft handoff and the system capability is meaning and helpful to the optimization of our communication system and to reach higher capability.This paper mainly discuss the soft handoff and the system capability's concept and the relationship between them in the CDMA communication system, including the concept of soft handoff, the analysis of soft handoff s factor, the process of soft handoff, CDMA system's capability estimation and the mainly factor of CDMA system's capability.Based on the IP-based CDMA communication system - CMT, this paper discussed the upwards problems from the point of view of implementation. At first this paper introduce the concept of soft handoff and the concept of system capability, including the capability calculation in the CDMA system, and two mainly manufacture calculation of CDMA equipment, the concept of soft handoff and the factor of deciding soft handoff and the process of soft handoff. And then the relationship of these two concepts is analyzed. Through theoretical analysis, we can conclude that the soft handoff is helpful in increasing the system's capability. The simulation results of the infection of soft handoff when mobile station in soft handoff state by the simulator CE4 verify this conclusion, therefore, we find a control proportion of soft handoff, Which is a suitable one for CDMA system. Moreover, this paper introduces the implementation of soft handoff and the A3A7 interface in this project. And the pivotal factors have been analyzed in soft handoff process. Then this paper introduced the implementation soft handoff in based IP cdma2000-1x communication system. And the improvement is introduced about this way. This paper introduced a soft handoff control proportion in CDMA communication system and it is used in CMT system. At last, this paper cites the results of the road test of CDMA communication system launched by the information industry department and analyzes the difference, two kinds of call drop are cited as well.