Decou pled space-time processing for equalization and co-channel interference cancellation in mobile communication systems

Abstract

In this article we propose a space-time processing strategy for combined equalization and (co-channel) interference cancellation in mobile communications. The principle of this strategy is to decouple interference cancellation and signal equalization in two processing stages. The so-called decoupled space-time (D-ST) processing strategy consists of employing an antenna arrav or a space-time filter to cancel the co-channel interfer~r signals in the space domain or in the space-time domain and an equalizer to perform intersymbol interference suppression in the time domain. This is achieved by optimizing the effective channel impulse response of the user of interest in such a way that the signal-to-interference-plus-noise ratio (SINR) at the input of the equalizer is maximized. In this contribution the optimization criteria for the D-ST strategy are presented and optimum receiver settings are derived. The bit-error-rate (BER) performance of adaptive D-ST processing structures is evaluated by means of link-level simulations under the COST 259 channel model. The results show superior performance of the D-ST receiver structures as compared to conventional approaches.