Abstract
CDMA is interference limited multiple access system. Power control is an effective way to reduce co-channel interference. Consequently, it can improve the system capacity. CDMA employs fast closed-loop power control in uplink in which signal-to-interference ratio (SIR) is estimated. Transmitting power is adjusted by comparing estimated SIR with desired SIR. In this paper a modified fixed step power control algorithm has been proposed, which can improve the performance of a CDMA system. The proposed algorithm produced a faster convergence and low outage probability compared to other power control algorithms discussed and analyzed to maintain the desired SIR target.