A method and system for using one H-ARQ process in communication systems having a Multiple Input Multiple Output antenna system. Information to be transmitted is first coded using a particular coding scheme and having a particular base coding rate. The coded information is then divided into groups of sub-blocks of coded information. Each group of sub-blocks of coded information contains one or more sub-blocks where the number of sub-blocks in a group is determined from current channel conditions of an antenna through which the group is to be transmitted. The groups are then rate matched and modulated based on the current channel conditions and transmitted through one or more antennas. For any retransmissions, the same coded information is used and is divided into groups of sub-blocks of coded information where at least one new group is associated with one of the plurality of antennas; the number of sub-blocks of coded information in a new group is based on current channel conditions experienced by the associated one antenna. Each group of sub-blocks is again rate matched and modulated before transmission. The rate matching and modulation parameters for any group of sub-blocks are determined by the channel conditions of the antenna through which that particular group is to be transmitted.