Variable-rate Retransmissions for Incremental Redundancy Hybrid ARQ

Leszek Szczecinski; Ciro Correa; Luciano Ahumada

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arXiv · 1207.0229

Variable-rate Retransmissions for Incremental Redundancy Hybrid ARQ

Leszek Szczecinski·Ciro Correa·Luciano Ahumada

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Abstract

The throughput achievable in truncated Hybrid ARQ protocol (HARQ) using incremental redundancy (IR) in analyzed when transmitting over a block-fading channel whose state is unknown at the transmitter. We allow the transmission lengths to vary, optimize them efficiently via dynamic programming, and show that such a variable-rate HARQ-IR provides gains with respect to a fixed-rate transmission in terms of increased throughput and decreased average number of transmissions, reducing at the same time the outage probability.

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Leszek Szczecinski, Ciro Correa, Luciano Ahumada. 2012-07-01. Variable-rate Retransmissions for Incremental Redundancy Hybrid ARQ. https://arxiv.org/abs/1207.0229

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