Adaptive antenna arrays for cochannel interference cancellation in space-time coded systems

Abstract

Space-time coding transmit diversity impairs the system's interference suppression ability because each transmitter generates multiple signals that appear independent to the receive antennas. We propose a multi-input-multi-output (MIMO) MMSE spatial filtering based adaptive antenna array method to suppress the cochannel interference (CCI) in space-time coded systems. It is shown that the proposed method can effectively suppress CCI while preserving the space-time structure, thereby, significantly improving the system's interference suppression ability without significant performance degradation.