Throughput Maximization of ARQ Transmission Protocol Employing Adaptive Modulation and Coding

Link adaptation techniques such as adaptive modulation and coding (AMC) aim at maximizing the throughput in wireless networks. In this paper, we propose new schemes allowing for the combining of AMC at the physical layer with automatic repeat request (ARQ) at the link layer. The method we propose formally maximizes the throughput under delay and packet-loss constraints. In addition, we change the basic paradigm of the AMC and propose to vary the modulation/coding levels depending on the state of the ARQ process. Compared to previous approaches, our results show that the proposed AMC scheme enhances the system’s throughput.