Research Of Power Control Algorithm In TD-SCDMA System

Power control, as the key technologies of the TD-SCDMA system, is studied in this paper. CDMA Code Division Multiple Access system is an interference- limited system, and power control technology can overcome the"near-far"effect,"Angle"effect and reduce a series of interferences. It can allow the system maintain high-quality communication, and also increase the capacity of the system. So power control technology is the core of all key technologies.Firstly, this paper introduces the development and the key technologies of the third-generation mobile communication system and then brief introduce the TD-SCDMA system. Then it discusses and analyzes the power control guidelines,classification and various options of the third generation mobile communication technology. After that, mainly researches and analyzes the power control technology of the TD-SCDMA system and proposes a new power control algorithm—Adaptive Variable step algorithm on the basis of the original algorithm. The algorithm increases an Adaptive Power Control Module to achieve on the basis of the traditional SIR Closed-loop power control, and the algorithm can not rely on the mobile base station and alone determine the power control step. The algorithm can be used as a mobile subsidiary functions and improve uplink TPC performance. Afterward detailed introduce the simulation model of the TD-SCDMA system adaptive power control algorithm, and finally compare and analyze the simulation performance of the adaptive control algorithm with the fixed-step algorithm. Also the wireless channel and the number of users on the impact of power control algorithms have also done a study. In all, the simulation results show that the adaptive power control algorithm has a better performance than the fixed step algorithm, also can reduce interference,converge rapidly and has good power control.