期刊名称:International Journal on Electrical Engineering and Informatics
印刷版ISSN:2085-6830
出版年度:2012
卷号:4
期号:3
出版社:School of Electrical Engineering and Informatics
摘要:In this paper, practical evaluation of power control technique to combat multipath fading in wireless mobile communications is performed using computer simulation. We consider two types of power control algorithm in Code Division Multiple Access (CDMA) system in this paper, namely fixed-step and variable step algorithms. Practical aspects of power control investigated in this paper are focused on the effect of power update step size, fading rates, and feedback transmission error on the power control performance. The results show that the fixed-step power control algorithm exhibits only a slightly lower performance than that of the variable step algorithm, and therefore is more desirable in practice to minimize the signaling bandwidth. The effect of fading rates on power control performance also shows that variable step algorithm outperforms the fixed step algorithm during high fading rates but gives a comparable performance when fading rates are low. Finally when feedback information is subject to transmission errors, the performance of variable-step algorithm degrades more significantly because it is more sensitive to command error than that of fixed-step algorithm.
关键词:Fixed step; multipath fading; power control; variable step.