Concatenation-assisted symbol-level combining scheme based on LR for MIMO systems with ARQ

In multiple-input multiple-output (MIMO) systems, it is well known that the lattice reduction (LR) can improve the performance significantly. LR aided (LRA) linear detectors achieve the full diversity with limit complexity. On the other hand, Automatic-repeat-request (ARQ) is another helpful tool for improving system's reliability, especially when packet data services play a more and more important role in the wireless communication now. In this paper, we propose a new receiver for MIMO systems with LR and ARQ. Based on the temporal correlation of a Rayleigh fading wireless MIMO channel and the features of retransmission, applying the results of LR in the last retransmission to the current retransmission can reduce the complexity of LR processing significantly. Simulation results corroborate our views.