Estimating the Maximum a Posteriori Threshold for Serially Concatenated Turbo Codes

Tarik Benaddi (1) , Arti D Yardi (2) , Charly Poulliat (2, 3) , Iryna Andriyanova (4)

1 Lab-STICC_IMTA_CID_TOMS
2 IRIT-SC - Signal et Communications
3 Toulouse INP - Institut National Polytechnique (Toulouse)
4 ETIS - UMR 8051 - Equipes Traitement de l'Information et Systèmes

We investigate the problem of estimating the maximum a posteriori (MAP) threshold for serially concatenated turbo codes. First, we provide a method to compute this MAP threshold using a numerical approximation of the EBP-GEXIT chart and the Maxwell construction. Second, we explore where the spatially coupled belief propagation (BP) threshold is located with respect to the previously computed MAP threshold and analyze the saturation phenomenon of such schemes. Simulation results indicate that the BP threshold of the spatially coupled turbo-codes saturates to the MAP threshold obtained using the EBP-GEXIT chart.

Domaines: Sciences de l'ingénieur [physics]

Tarik Benaddi, Arti D Yardi, Charly Poulliat, Iryna Andriyanova. Estimating the Maximum a Posteriori Threshold for Serially Concatenated Turbo Codes. 2019 IEEE International Symposium on Information Theory (ISIT), Jul 2019, Paris, France. pp.1347-1351, ⟨10.1109/ISIT.2019.8849536⟩. ⟨hal-02552645⟩