MIMO detection based on averaging Gaussian projections

We propose a new detection algorithm for MIMO communication systems employing a two-dimensional marginal of the Gaussian approximation of the exact discrete distribution of the transmitted data given the received data. From the 2D distributions we derive one-dimensional marginals by averaging all the 2D joint distributions related to a single input symbol. We prove that this strategy to obtain a 1D distribution from a set of not necessarily consistent 2D distributions is optimal (for a specified criterion). The improved performance of the proposed algorithm is demonstrated on several instances of the problem of MIMO detection.