The Power Control Algorithm Of TD-SCDMA

Radio resource management is the key and hot research topic of the third generation and future mobile communication system, the technique includes switching control part, call admission control part, power control part,packet scheduling part, load control part, mobility management, etc. Intelligent use of these algorithms can effectively keep the QOS requirements of various services of the third generation communication, optimize the allocation of limited system resources, improve the utilization ratio of resources. This paper comprehensively analyzes the power control in the TD-SCDMA, proposes improved algorithm on the basis of the currently existing algorithm from the aspects of the factors that influence power and optimization of the power control algorithm.This paper analyzes the influence of velocity, step length, length of control command word on the power control of TD-SCDMA, the TPC command word which is transmitted through the channel may be wrongly judged when the channel environment is poor, wrong command word may cause the sender to make a mistaken judgment, the sender is supposed to enlarge power but reduce transmitting power, for example, which will definitely leads to the drop in the quality of communication, even drop of words. This paper analyzes effect of power control on system in such circumstances, presents an improved algorithm on the basis of existing power control algorithms. We analyze the quality of received signal to learn the current quality of channel before the inner-loop power control, when the channel environment is good the existing power control algorithm is used, and when the channel environment is poor, user will get power compensation. Raise its transmitting power until the channel environment turns to good and returns to the inner-loop power control. And we can reduce the harm of worsening of channel on the power control.The analysis and simulation results indicates that the improved algorithm does not have effect on the implementation of power control algorithm when the channel environment is good, and it will enlarge the power of the user initiatively when the channel environment is poor, and in this way the system performance is effectively improved, optimum distribution of resources is implemented. In the latter context, we compares the improvement of the system performance by the improved algorithm through simulation, analyze and compare the effect of improved algorithm in different conditions in the meantime.