Research And Simulation Based On The SIR In TD-SCDMA Power Control Algorithm

With the development of mobile communication systems, our life has been inseparable from 3G.Which,TD-SCDMA 3G technology is one of our own research and development.This paper studies the TD-SCDMA system key technologies: power control technology. Code Division Multiple Access (CDMA) system, "proximity effect" and "MAI" has been the most difficult problem .To resolve this issue is to control the power, namely accurate power control can keep the power and effectiveness of the system capacity can be increased.This paper describes the principles and mechanisms of TD-SCDMA system power control .For existing fixed step uplink power control algorithm can not keep changing the channel fast fading problems in depth, this paper presents an improved power control algorithm. Algorithm based SINR measurement, SINR prediction, which can reflect the type of channel variation,and finally to a more accurate value of the outer ring to provide for the target SINR, and generates a power control command, and then the Markov state length of the power to make reasonable adjustments depending on the power control step. Compared with the traditional power control algorithm, the improved algorithm for step selection has more space, improved power control. Finally, the simulation using MATLAB software, launch TD-SCDMA transmission system established in the simulation model of the physical layer and the data link, the receiver model. The simulation results include: improved performance comparison algorithm and fixed step algorithm and improved algorithm to improve system performance analysis. Simulation results show that the improved algorithm is better than traditional fixed-step algorithm,more effective control of transmit power,improve system stability.