Decision feedback turbo equalization for space-time coded systems

We present a novel turbo equalization structure for space-time coded systems. It is based on performing channel equalization via a decision feedback equalizer (DFE) designed using a novel maximum likelihood criterion. The resulting optimization problem is solved using the space-alternating generalized EM (SAGE) algorithm. This results in expressions for the forward and backward filters of the DFE that take large benefit from the more and more refined estimations of the transmitted symbols iteratively obtained by the outer decoder.