Pilot-channel-aided successive interference cancellation for uplink WCDMA systems

Abstract

In this paper, a pilot-channel-aided successive-interference-cancellation (SIC) scheme for uplink wideband code-division multiple-access system is presented. In order to alleviate the interferences from other users' pilot-channel signals, this scheme performs pilot-channel-signal removal (PCSR) for all users before data detection. Three ordering methods for successive-cancellation process are discussed and compared in the aspect of architecture, latency, computational complexity, and error performance. In addition, channel estimation performed independently with the pilot-channel of each user is taken into consideration in the analyses. The pilot-channel-aided SIC performs variously with different ordering methods, pilot-to-traffic amplitude. ratios, grouping intervals, power-distribution ratios, and propagation conditions. From our analyses and simulations, the SIC with ordering based on RAKE outputs at the first stage in properly chosen grouping interval is suggested over multipath fading channels when error performance and practicability are jointly concerned.