1. A method for decoding a signal vector in a multiple-input multiple-output (MIMO) hybrid automatic repeat request (HARQ) transmission scheme, the method comprising: receiving multiple signal vectors corresponding to multiple asynchronous transmissions of a common transmit signal vector, the received signal vectors comprising a first signal vector corresponding to a transmission of the common transmit signal vector and a second signal vector corresponding to a retransmission of the common transmit signal vector, wherein each of the received signal vectors is associated with a channel state matrix; concatenating the received signal vectors into a combined received signal vector; concatenating each channel state matrix associated with the received signal vectors into a combined channel state matrix; after the concatenations, matched filtering the combined received signal vector using the combined channel state matrix; decision feedback equalizing the matched filtered combined received signal vector, wherein the decision feedback equalizing comprises incrementally computing a projected received signal, {tilde over (w)} n , and a triangular matrix {tilde over (R)} n for an n-th transmission of the common transmit signal vector where w ~ n = Q n â¢ * ~ â¡ [ w ~ n - 1 y n ] , H ~ n = [ R ~ n - 1 H n ] , and where a QR decomposition of the channel state matrix for the n-th transmission of the common transmit signal vector {tilde over (H)} n is given by 
 {tilde over (H)} n ={tilde over (Q)} n {tilde over (R)} n. and where H 1 =Q 1 R 1 , {tilde over (w)} 1 =Q 1 *y 1 , and y n is the n-th received signal vector corresponding to the common transmit signal vector; and decoding an estimated transmit signal vector from the equalized combined received signal vector.