SIC Detector for Hi Orthogonal Space-Time Block Coded System over Time-Varying Rayleigh-Fading Channel

An important assumption in all orthogonal space-time block coded (OSTBC) systems is that the channel behaves same throughout the codeword length (i.e. quasi-static). However, if the channel is time-varying then the conventional OSTBC detector can suffer from a large error floor at high signal-to-noise ratios. In this paper, the impact of a time-varying, Rayleigh fading channel on the performance of an H_i system is considered. A successive interference cancellation (SIC) technique is proposed to alleviate the effects of a time-varying channel. Performance comparison between the existing conventional, parallel interference cancellation (PIC) detector and the proposed SIC detector shows that the SIC detector performs better than the conventional detector and worse than the PIC detector if equal-energy symbols are employed. However, it outperforms both the detectors if unequal energy symbols are used.