Multipath interference canceller for high-speed packet transmission with adaptive modulation and coding scheme in W-CDMA forward link

This paper proposes a multipath interference canceller (MPIC) associated with orthogonal code-multiplexing with orthogonal variable spreading factor (OVSF) channelization codes that achieves high throughput performance with adaptive data modulation in multipath fading channels in the W-CDMA forward link, and evaluates its throughput performance by computer simulation. The simulation results elucidate that sufficient multipath interference suppression is achieved by a four-stage MPIC with 6-12 orthogonal code-multiplexing using one iterative channel estimation with pilot and decision feedback data symbols hard-decided after RAKE combining. We show that the maximum peak throughput using MPIC is approximately 2.1 fold that without MPIC in a 2-path Rayleigh fading channel and that the peak throughput of 8.0 Mbps is achieved using 64QAM data modulation within a 5-MHz bandwidth. Furthermore, the required average E_b/N₀ for satisfying the same throughput with MPIC is decreased by more than 2.0 dB