An SVD-aided list demapper for iterative coded-MIMO receivers

The list demapper has been widely implemented in a coded multiple-input multiple-output (MIMO) receiver, where only a part of total signal vectors are examined in the calculation of likelihood ratio for low complexity. Generally, the list is generated either in the original or the lattice-reduced domain. In the latter, thanks to the operation of lattice reduction (LR), a better-conditioned MIMO channel is obtained, and the adverse effect of noise enhancement is mitigated in the generation of list and thus can achieve a better performance. In this paper, a new singular-value-decomposition (SVD)-aided list demapper is proposed for the iterative coded-MIMO receiver. With SVD, the layer interference incurred in the operation of LR can be avoided, and that renders the SVD-aided list demapper a lower complexity. Computer simulations have confirmed that the proposed demapper has better performance-complexity tradeoffs as compared to the best-performed LR-aided methods in the literature.