Date Added: Jul 2011
In this paper, the authors develop and analyze low-complexity approaches that they call incremental Multiple-Input Multiple-Output (IMIMO) for exploiting multiple antennas for reliable high-rate communications in wireless systems. The proposed schemes leverage consecutive uses of a single transmit antenna combined with Automatic Repeat reQuest (ARQ) feedback, possibly with multiple receive antennas. Unlike Multiple-Input Multiple-Output (MIMO) communications without feedback, the schemes they propose allow for low-complexity transmitters and receivers because they do not require a space-time encoder or decoder. They compare the performance of IMIMO schemes with the corresponding MIMO system without feedback using outage probability as the metric for comparison.