Low complexity iterative MIMO receiver based on successive soft interference-cancellation and MMSE spatial-filtering

For MIMO systems, the ST-BICM approach using iterative processing has been recognized as a method for achieving near-capacity performance. However, the a posteriori probability calculator in the MIMO detector, relying on exhaustive or partial search of candidate bit vectors, is not amenable to practical implementation at high rates ( ¿ 16 raw bits per channel use) due its exponential complexity in rate. On the other hand, recently developed low complexity single stream demappers based on a parallel approach, while yielding comparable performance in ideal conditions, suffer significant performance loss in several practical scenarios. In this paper, we propose a novel demapper which closes the performance gap between the low complexity detectors based on single stream demapping and their exponentially complex counterparts.