Tree-Based Reparameterization for Symbol Detection in Spatially Multiplexed MIMO Systems in Frequency Flat Fading

Reduced complexity detection of spatially multiplexed data transmissions under frequency flat fading is considered. Noting that the optimal detection is the generation of marginal distributions of a joint probability distribution, we use the approximate marginal generating algorithm termed the tree-based reparameterization. The resulting system complexity is having an order which is less than quadratic in the number of transmit antennas. Simulation of a 8 times 8 BPSK system shows a coded bit error rate of 10
^-3
at an SNR level of only IdB greater than required by the optimal method