A VLSI 8x8 MIMO near-ML decoder engine

Multiple-Input Multiple-Output (MIMO) systems are of significant interest due to their ability to increase the capacity of wireless communications Systems, but for these to be useful they must also be practical for implementation in VLSI circuits. A particularly difficult part of these systems is the decoder, where the optimal maximum-likelihood (ML) solution is desirable, but cannot be directly implemented due to its exponential complexity. The paper presents the first published 8 x 8 MIMO detection engine with an integrated channel preprocessing unit, achieving near-ML BER results at 57.6Mbps, using QPSK in an extended HSDPA application. Other novelties include the high speed sorting mechanism and power saving features.