A decoder, such as for example an MMSE MIMO decoder, and a method for decoding are described. An input channel matrix is obtained, and an extended channel matrix of the input channel matrix is generated. The extended channel matrix is triangularized to provide a triangularized matrix, and the triangularized matrix is inverted to provide an inverted triangular matrix. A left matrix multiplication result matrix associated with multiplication of the input channel matrix and the inverted triangular matrix is generated, and a weight matrix from the left matrix multiplication result matrix and the inverted triangular matrix is generated. A received symbols matrix is obtained, and a weighted estimation is generated and output using the weight matrix and the received symbols matrix to provide an estimate of a transmit symbols matrix for output of estimated data symbols.