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arXiv · 1409.3330

Finite Block-length Analysis of the Incremental Redundancy HARQ

Behrooz Makki·Tommy Svensson·Michele Zorzi
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Abstract

This letter studies the power-limited throughput of a communication system utilizing incremental redundancy (INR) hybrid automatic repeat request (HARQ). We use some recent results on the achievable rates of finite-length codes to analyze the system performance. With codewords of finite length, we derive closed-form expressions for the outage probabilities of INR HARQ and study the throughput in the cases with variable-length coding. Moreover, we evaluate the effect of feedback delay on the throughput and derive sufficient conditions for the usefulness of the HARQ protocols, in terms of power-limited throughput. The results show that, for a large range of HARQ feedback delays, the throughput is increased by finite-length coding INR HARQ, if the sub-codeword lengths are properly adapted.

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Behrooz Makki, Tommy Svensson, Michele Zorzi. 2014-09-17. Finite Block-length Analysis of the Incremental Redundancy HARQ. https://doi.org/10.1109/lwc.2014.2353059

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