In a CDMA data communication system capable of variable rate data transmission, a time-division power assignment cyclically reduces the carrier power level to at least one sector to reduce interference in neighboring sectors. The base station determines a time-division power assignment for each sector and generates signals according to the power assignment. The mobile unit generates filter coefficients corresponding to each power level. The mobile unit estimates Carrier Signal-to-Interference (C/I) to determine a data rate for each power level. Previous iterations of the equalizer are stored and used to refine future estimates.