DFE-Based Receiver Implementation for MIMO Systems Employing Hybrid ARQ

The implementation of decision feedback equalization-based receivers for MIMO systems that employ hybrid ARQ (HARQ) is considered. It is shown how the theory of MIMO decision feedback equalization can be applied to derive optimal DFE architectures for the case of MIMO HARQ. Incremental structures are proposed that reduce the implementation complexity of the DFE and the memory requirements at the receiver without loss in performance. Moreover, sub-optimal, post-equalization combining architectures are examined that simplify the receiver at the cost of performance loss.