X-Structured Precoder Design for Spatial Multiplexing MIMO Systems
In Multiple-Input Multiple-Output (MIMO) transmission, precoding has been considered a promising method to improve the system performance. In general, the precoder design criterion depends on the detector used at the receiver. For the Maximum-Likelihood (ML) detector, the optimum precoder design criterion is equivalent to maximizing the minimum distance of received signal constellations. Several precoding methods have been developed in the literature. However, most of them use numerical searches to derive the pre-coders and require table look-ups in real-time applications. In this paper, the authors propose a simple but effective method to solve the problem.