Forward link capacity based on interference characteristics in CDMA systems

Interference is one of the key factors in determining the capacity and performance of CDMA (code division multiple access) systems. In the forward link, the interference consist of a non-stationary process from the multipath of the same cell and stationary Gaussian process resulting from the background noise and interfering signals of other cells, which vary according to the number of multipaths and mobile´s position. We investigated the interference characteristics and the required E_b /I_t in WCDMA environments adopting the described interference model. The forward link capacity can be obtained from the results under uniform user distribution throughout the cell. The effect of outer loop power control on the capacity, by which the received E_b/I_t is set exactly to the target value at each position, is also investigated