Modified distributed constrained power control using reference model in CDMA cellular systems

The current paper proposes a modified distributed power control (M-DCPC) algorithm that can improve the performance of a CDMA power control system. The control performance of the proposed method is verified using two performance measures: the SIR response of each mobile and the outage probability in a cell. The transient and steady state responses are also compared with those for DCPC, CSOPC, and LQPC. As regards the SIR response, in simulations, the M-DCPC algorithm produced a faster convergence and lower overshoot in transient time than the other power control algorithms when the desired SIR value was varying. For the outage probability, M-DCPC converged to a fixed outage rate faster than CSOPC while also maintaining the system capacity to make as high a connection as CSOPC. In particular, when the desired SIR was varying, CSOPC showed an abrupt outage probability increase during the desired SIR increase, yet M-DCPC was unaffected. Accordingly, M-DCPC was confirmed to be more effective than any of the other power control algorithms.