The Research And Application Of Some Key Optimization Technologies In CDMA Network

With the development of CDMA network, its service coverage becomes more and more extensive. Considering the CDMA system's inner interference and the fact that there are more base stations and the distance between them become nearer, some weak coverage areas come into existence. In this kind of area there is no main pilot signal, so it is called pilot pollution area. In this area, the mobile network users may fail to call and get broke off during a call.In the real network, if a mobile network user is in a pilot pollution area, his cell phone will do handoff frequently. It will do soft handoff or softer handoff between several pilot signals. This will cost him more time and more transmitted power to connect or even make him fail to connect. In this process, soft handoff technology does help to reverse diversity receiving, but it will occupy some system resource (walsh code and base station's power) making the system capacity decrease.This thesis does research on the performance difference between the hard handoff and soft handoff and proposes a new calculation method to calculate the effect of handoff technology do to the mobile station's transmitted power and the cells'coverage. Then it gives some simulation results. Another work of this thesis is to research and develop a pilot analyzing module in the CDMA network optimization platform according to some pilot pollution knowledge and analyzing rules. This platform provides users a strong tool to analyze pilot pollution.