Polar Coded Repetition for Low-Capacity Channels

Fariba Abbasi; Hessam Mahdavifar; Emanuele Viterbo

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arXiv · 2010.16144

Polar Coded Repetition for Low-Capacity Channels

Fariba Abbasi·Hessam Mahdavifar·Emanuele Viterbo

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Abstract

Constructing efficient low-rate error-correcting codes with low-complexity encoding and decoding have become increasingly important for applications involving ultra-low-power devices such as Internet-of-Things (IoT) networks. To this end, schemes based on concatenating the state-of-the-art codes at moderate rates with repetition codes have emerged as practical solutions deployed in various standards. In this paper, we propose a novel mechanism for concatenating outer polar codes with inner repetition codes which we refer to as polar coded repetition. More specifically, we propose to transmit a slightly modified polar codeword by deviating from Arikan's standard 2 x 2 Kernel in a certain number of polarization recursions at each repetition block. We show how this modification can improve the asymptotic achievable rate of the polar-repetition scheme, while ensuring that the overall encoding and decoding complexity is kept almost the same. The achievable rate is analyzed for the binary erasure channels (BEC).

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Fariba Abbasi, Hessam Mahdavifar, Emanuele Viterbo. 2020-10-30. Polar Coded Repetition for Low-Capacity Channels. https://arxiv.org/abs/2010.16144

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