Design of block-based linear MMSE precoding and equalisation for broadband MIMO relay networks

This paper addresses the design of MMSE block-based linear precoding and equalisation for relayed communications over frequency-selective MIMO channels. Using a combination of leading zero and trailing zero guard intervals to eliminate inter-block interference, jointly optimal MMSE designs for the block processors in the relay layer and the destination are derived under the assumption of channel state information availability across most of the link. This proposed technique is compared to an extension of state-of-the-art block based methods, which are operated back-to-back across the link and may contain an intermittent non-linear detection stage in the relay. Using the latter as a benchmark, simulation results highlight the benefit of the proposed design for broadband relay communications.