Sensitivity of advanced wideband CDMA network capacity to various channel and system parameter imperfections

We analyze capacity losses in advanced wideband code division multiple access (WCDMA) networks due to imperfections in the estimation of the system and channel parameters. Key components in the analysis are multiple access intracell interference (MAI), intercell interference, efficiency of the interference cancellation, multipath intensity profile, efficiency of the RAKE combiner, inefficiency of signal and channel parameter estimation and additive white Gaussian noise. Receiver structures are based on a conventional matched filter RAKE combiner that can be supported by either a linear or nonlinear interference canceler. Both the equal gain and maximal ratio combining techniques are considered. Results show that significant capacity gains can be achieved by interference cancellation in comparison to the conventional techniques. However, the capacity gain may be completely lost in fast fading channels due to the estimation imperfections