Title :
Predictive power estimators in CDMA closed loop power control
Author :
Tanskanen, J.M.A. ; Huang, A. ; Hartimo, I.O.
Author_Institution :
Lab. of Signal Process. & Comput. Technol., Helsinki Univ. of Technol., Espoo, Finland
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
Keywords :
Rayleigh channels; closed loop systems; code division multiple access; digital simulation; land mobile radio; optimisation; power control; prediction theory; radio links; radio transmitters; radiofrequency interference; telecommunication control; CDMA closed loop power control; Rayleigh fading; Wiener model; closed loop transmitter power control; closed power control loop simulators; complex-valued signals; delay sensitive closed control loops; guaranteed positive output; high computational efficiency; interference limited system; mobile CDMA communications systems; multiuser CDMA uplink; partially-optimized power estimators; polynomial predictors; power control system; prediction step; predictive power estimators; quadratic filters; signal power estimation; single-user CDMA uplink; user capacity; Computational efficiency; Delay estimation; Design methodology; Design optimization; Multiaccess communication; Power control; Power system modeling; Predictive models; Signal design; Transmitters;
Conference_Titel :
Vehicular Technology Conference, 1998. VTC 98. 48th IEEE
Conference_Location :
Ottawa, Ont.
Print_ISBN :
0-7803-4320-4
DOI :
10.1109/VETEC.1998.686408