Superposition-Aided Delay-Constrained Hybrid Automatic Repeat ReQuest

A novel Multiplexed Hybrid Automatic Repeat reQuest (M-HARQ) scheme is proposed and compared with the conventional scheme in terms of its energy efficiency while satisfying specific delay constraints, where the best transmission strategy is discussed for both schemes. By employing the proposed scheme, the transmission rate and power can be reduced while maintaining the maximum energy efficiency and meeting specific delay constraints. Alternatively, the cell-radius distance may be extended by about 10%, which results in a coverage area extension by a factor of 1.21.