Rate Adaptation for Secure HARQ Protocols

• Published in: IEEE transactions on information forensics and security Vol. 13; no. 12; pp. 2981 - 2994
• Main Authors: Le Treust, Mael, Szczecinski, Leszek, Labeau, Fabrice
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.12.2018; The Institute of Electrical and Electronics Engineers, Inc. (IEEE); Institute of Electrical and Electronics Engineers
• Subjects: Automatic repeat request; channel state information; Channels; Decoding; Encoding; Humanities and Social Sciences; Hybrid automatic repeat request; Library and information sciences; physical layer security; Power system reliability; Probability; Protocols; Redundancy; Reliability; secrecy outage probability; secrecy throughput; Splitting; state-dependent wiretap channel; Statistical analysis; Throughput; channel state information; Hybrid automatic repeat request; state-dependent wiretap channel; secrecy outage probability and secrecy throughput; physical layer security
• ISSN: 1556-6013; 1556-6021
• DOI: 10.1109/TIFS.2018.2833799

This paper investigates the incremental-redundancy hybrid-automatic repeat request (IR-HARQ) transmission over independent block-fading channels in the presence of an eavesdropper, where the secrecy of the transmission is ensured via introduction of dummy messages. Since the encoder only knows the statistics of the channel state, the secrecy and the reliability are defined in a probabilistic framework. Unlike previous works on this subject, we design a coding strategy tailored to IR-HARQ by splitting the dummy-message rate over several rate parameters. These additional degrees of freedom improve the match between the dummy-message rates and the realizations of the eavesdropper channels. We evaluate the performance in terms of secrecy outage probability, connection outage probability, and throughput and compare it with the benchmark paper by Tang et al. Numerical examples illustrate that, comparing to existing alternatives, splitting of the dummy-message rate provides higher throughput and lower expected duration/average delay.