An Improved SCFlip Decoder for Polar Codes

Ludovic Chandesris (1, 2) , Valentin Savin (1) , D Declercq (2)

1 CEA-LETI - Commissariat à l'énergie atomique et aux énergies alternatives - Laboratoire d'Electronique et de Technologie de l'Information
2 ETIS - UMR 8051 - Equipes Traitement de l'Information et Systèmes

This paper focuses on the recently introduced Successive Cancellation Flip (SCFlip) decoder of polar codes. Our contribution is twofold. First, we propose the use of an optimized metric to determine the flipping positions within the SCFlip decoder, which improves its ability to find the first error that occurred during the initial SC decoding attempt. We also show that the proposed metric allows closely approaching the performance of an ideal SCFlip decoder. Second, we introduce a generalisation of the SCFlip decoder to a number of í µí¼” nested flips, denoted by SCFlip-í µí¼”, using a similar optimized metric to determine the positions of the nested flips. We show that the SCFlip-2 decoder yields significant gains in terms of decoding performance and competes with the performance of the CRC-aided SC-List decoder with list size í µí°¿ = 4, while having an average decoding complexity similar to that of the standard SC decoding, at medium to high signal to noise ratio.

Keywords: Polar Codes; SCFlip decoding; order statistic decoding

Domains: Engineering Sciences [physics]

Ludovic Chandesris, Valentin Savin, D Declercq. An Improved SCFlip Decoder for Polar Codes. Global Communications Conference (GLOBECOM), 2016 IEEE, Dec 2016, Washington, DC, United States. pp.1 - 6, ⟨10.1109/GLOCOM.2016.7841594⟩. ⟨cea-01573437⟩