Clipping demapper for LDPC decoding in impulsive channel

Hassen Benmaad (1) , Alban Goupil (1) , Laurent Clavier (2, 3, 4) , Guillaume Gelle (1)

1 CRESTIC - Centre de Recherche en Sciences et Technologies de l'Information et de la Communication - EA 3804
2 Institut TELECOM/TELECOM Lille1
3 IEMN - Institut d’Électronique, de Microélectronique et de Nanotechnologie - UMR 8520
4 IRCICA - Institut de Recherche sur les Composants logiciels et matériels pour l'Information et la Communication Avancé - USR 3380

This paper deals with the performance of Low-Density Parity-Check codes in impulsive interference modeled by α-stable random variables. In case of α-stable noise, the optimal inputs of the belief propagation decoder are complex to obtain. We propose to use the simple clipping approach that reduces the impact of large noise values. Our main contribution is to give three different approaches to obtain the parameters of the clipping function and to assess the performance of the decoder. We show that a look-up table whose values are pre-determined, thanks to the Density Evolution tool, is the most efficient approach.

Keywords: LDPC codes; α-stable interference; density evolution; clipping

Domains: Signal and Image processing; Signal and Image Processing

Hassen Benmaad, Alban Goupil, Laurent Clavier, Guillaume Gelle. Clipping demapper for LDPC decoding in impulsive channel. IEEE Communications Letters, 2013, 17 (5), pp.968-971. ⟨10.1109/LCOMM.2013.031913.130060⟩. ⟨hal-00851898⟩