Markov Models of ARQ and HARQ Techniques for the Wireless Channel

This paper reviews papers using Markov models for ARQ and HARQ techniques. In particular, the authors classify existing implementation of such models according to the kind of ARQ system and the modeled delay terms. The analysis of the delay statistics for SR ARQ is important as it enables system design under statistical delay requirements. Retransmission-based error correction schemes for information transmission are widely utilized to provide a reliable service, especially on error-prone channels such as the wireless medium. In this sense, an analytical description of the protocols belonging to the ARQ (Automatic Retransmission reQuest) and Hybrid ARQ (HARQ) can be an extremely useful instrument for researchers. In the literature, several models have been proposed to study ARQ and HARQ.