An Improved Channel Quantization Method for Performance Evaluation of Incremental Redundancy HARQ Based on Reliable Channel Regions

Abstract—In this paper, we investigate useful channel represen-tations for Incremental Redundancy Hybrid ARQ. When these techniques are employed, parts of the codeword are transmitted over different channel realizations. We focus on coding perfor-mance models where the error probability is asymptotically zero if the channel parameters of these realizations fall within a given region. To map this region in a compact but still precise manner, we adopt a Finite-State Channel model, a methodology which has been often used in the past for the study of the performance of ARQ protocols, and we propose a novel method to derive efficient channel partitioning rules, i.e., a code-matched quantization of the channel state. We present results showing the performance of our proposed method and its capability of representing the channel in a compact and accurate way. Index Terms—Channel modeling, hybrid automatic repeat request, Markov processes, error correction techniques, channel coding. I