Adaptive step-size algorithm for the interference canceller in the space-time coded DS-CDMA system

In this letter, we propose an adaptive step-size algorithm for the adaptive interference canceller (AIC) in the space-time coded DS-CDMA system. To improve the performance of the fixed step-size AIC (FS-AIC), the regular adaptive step-size algorithm is extended in complex domain and applied to the joint AIC and ML decoder scheme. Simulation results show that the joint adaptive step-size AIC (AS-AIC) and ML decoder scheme using the proposed algorithm has better performance than not only the conventional ML decoder but also the joint FS-AIC and ML decoder scheme without much increase of the decoding delay and complexity.