System aspects of WCDMA uplink parallel interference cancellation

Interference cancellation (IC) has the potential to significantly improve the system capacity of CDMA systems using conventional RAKE receivers. The main objective in this paper is to quantify the potential improvements of parallel interference cancellation (PIC) in terms of system aspects such as capacity gain, coverage gain, relation to power control etc. This is conducted through approximate estimates, system simulations with realistic receiver prototype models, and single-cell field trials with a limited-complexity PIC prototype. It is concluded that the approximate expressions estimate capacity and coverage gains with acceptable accuracy. Moreover, the WCDMA uplink is configured with a fixed power offset between dedicated physical control and data channels. PIC fits well into the system architecture and power control design, which put limitations on other IC structures, such as successive IC (SIC).

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