MSSTC-Based MIMO-ARQ System With Two Transmit Antennas

A multiple-input-multiple-output automatic repeat request (MIMO-ARQ) system with two transmit antennas using modified multistrata space-time codes (MSSTCs) is proposed. We propose a low-complexity detection algorithm composed of interlayer interference cancelation, linear postprocessing after which intralayer interference does not exist, and a slicing operation. The proposed detection algorithm is performed in a successive layer-by-layer manner through multiple transmissions. Phases of two layers are adaptively assigned to mitigate the effect of interlayer interference through multiple transmissions with a low amount of additional feedback system overhead. We analytically obtain the approximation for the block error rate (BLER) of the proposed MIMO-ARQ system, and based on this, we propose a transmit power-allocation scheme, which minimizes the BLER of the MIMO-ARQ system at each transmission round. Numerical analyses and simulations show that the proposed MIMO-ARQ system results in low BLER and high throughput performances with low computational complexity.