CDMA mobile systems with tailor made power control to each mobile station

Power control is an important issue in the capacity of DS-CDMA cellular systems to tackle the near-far problem, co-channel interference and varying signal strength in fading channels. In this paper, we propose an adaptive signal-interference-ratio (SIR) feedback power control technique so that the SIR threshold control level of each mobile station will be individually adjusted with respect to its own radio link condition. Fuzzy logic control is applied to the power control and the SIR threshold level in this paper. This new technique results in lower outage probability and thus enhances traffic capacity, especially in poor cochannel interference conditions.