Predictive power estimators in CDMA closed loop power control

Abstract

The estimation of signal power is considered. Methods of designing optimized and partially-optimized power estimators, based on the Wiener model, for complex-valued signals are presented. Our application is a predictive received power level estimation in closed loop transmitter power control of mobile CDMA communications systems. The proposed estimators have the benefits of guaranteed positive output, high computational efficiency as compared to quadratic filters, and providing for a predescribed prediction step, all the aspects being of great interest when applying the estimators in delay sensitive closed control loops. The user capacity of a CDMA communications system is generally found to be greatly interference limited, and thus proper power control system functioning is of paramount interest. The partially-optimized power estimators are simulated along with Heinonen-Neuvo (1988) polynomial predictors in singleand multiuser CDMA uplink closed power control loop simulators.