Encoding and Decoding for Turbo-Like Codes

Generally, the major part of communication systems use Turbo Codes (TC) and/or Low-Density Parity-Check (LDPC) codes to protect the data to transmit (e.g. 3GPPLTE, IEEE 802.11p, IEEE 802.16, etc). Given that these coding strategies share similarities (e.g. two stage iterative decoding, Log-Likelihood ratio based, etc.) in their respective encoding and decoding parts it is possible to express one code in terms of the other one. However, this conversion has some constraints, which have been formulated in this paper for different structures of convolutional codes. If these constraints are fulfilled the Bit Error Rate (BER) of Turbo Code using Believe Propagation (BP) decoding is quite similar to that offers the Bahl-Cocke-Jelinek-Raviv (BCJR) decoding.