Iterative decoding of product codes with a priori information over a Gaussian channel forstill image transmission

Abdessamad El Baz (1) , Ramesh Pyndiah (1) , Basel Solaiman (1) , Omar Aitsab (1)

1 SC - Département Signal et Communications

In this paper we propose an optimized transmission system for still images. This system comprises a VQ source encoder with a compression rate of 9. The source data is encoded using a BCH product code and mapped on a 16-QAM constellation. The codebook and channel encoder have been optimized to minimize distortion in presence of transmission errors. We use a new joint source-channel turbo decoding algorithm of the product code. As compared to classical channel decoding algorithms (soft decoding), we obtain an improvement of 0.7 dB in terms of coding gain for a BER of 10/sup -5/. The PSNR of the received image exhibits an improvement of 11 dB as compared to conventional turbo decoding at low SNRs.

Mots clés: 16-QAM

Domaines: Traitement du signal et de l'image [eess.SP]

Abdessamad El Baz, Ramesh Pyndiah, Basel Solaiman, Omar Aitsab. Iterative decoding of product codes with a priori information over a Gaussian channel forstill image transmission. IEEE Globecom'99: Seamless Interconnection for Universal Services. Global Telecommunications Conference, Dec 1999, Rio De Janeiro, Brésil. ⟨10.1109/GLOCOM.1999.831771⟩. ⟨hal-02147904⟩