Low Complexity Soft Output MIMO Decoder

A method and processing block for receiving data transmitted in a MIMO system is provided. Data is transmitted as a transmit vector of values from multiple transmitting antennas and received as a receive vector of values at multiple receiving antennas. Candidate vectors are determined based on each of a plurality of constellation points of the constellation configuration used in the transmission scheme. A channel matrix is decomposed into a unitary matrix and a triangular matrix, such that a relationship links: (i) a function of the unitary matrix and the receive vector, and (ii) a multiplication of the triangular matrix and the transmit vector. A best candidate vector from the set of candidate vectors is utilized for the computation of soft bits representing the values of the transmit vector.