| This dissertation is concerned with the power control in cdma2000 wireless multimedia communication systems, which is also one of the key techniques in the third generation mobile communication systems.⑴The fundamental principles of centralized and distributed power control algorithms are summarized, including the criterions and the model of power control, some existing algorithms of centralized and distributed power control.⑵This dissertation first analyzes the cdma2000 protocols in details and the system simulation methodology(Presented by 3GPP2), and then establishes the computer simulation platform of cdma2000 voice service based on the OPNET simulation tool. This platform models the following simulation scenarios, such as the movement of mobile station, multi-cells communication. Many RRM algorithms like handoff, rate allocation, power control and so on are also implemented by the platform.⑶Aiming at resolving the problems existing in the cdma2000 protocols like PC bits delay and fixed-PC-step, the dissertation presents a integrated power control scheme in CDMA up-link System, using doppler estimation and channel prediction. In addition, the dissertation introduces the distance information of mobile stations in resolving the problems and presents another integrated power control scheme, making use of doppler estimation and distance information. Simulation results show that the accuracy of power control has been improved by using these two modified power control schemes.⑷The main goal of 3G communication system is to maximize the system throughput. The power control technology itself cannot satisfy this design goal, so it should be combined with the rate control technology. This dissertation introduces the criterion and the model of rate control, and also presents the existing research achievements of combined power and rate control. The combined power and rate control scheme used in the cdma2000 system has also been discussed in this dissertation. |
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