Data link control for multiple input multiple output wireless systems

This paper investigates the adaptation of data link error control protocols to be more efficient over MIMO wireless links. Data link mechanisms control, among other things, the transmission errors at the link layer, whereas MIMO is a physical layer technology that handles the wireless link with a notably high efficiency and flexibility. A new cross layer protocol is proposed in this paper in order to improve the performance of error control mechanism by making use of the multi-channel transmission characteristics. The main idea is to divide each link layer data unit (block) into sub-blocks and transmit the sub-blocks from different transmit antennas and therefore take advantage of the spatial "diversity". Besides, the division helps the receiver to recognize some error-free parts of a block; consequently new algorithms that exploit this feature are proposed and analyzed. In addition, different methods for providing higher link reliability to retransmitted data are explored.