Design of turbo-like codes for short frames

Turbo codes have been shown to yield very good performance for long block sizes. However, their performance degrades when the frame size decreases. Furthermore, decoding turbo codes with the maximum a posteriori (MAP) algorithm or the soft output Viterbi algorithm (SOVA) is quite complex. We proposed a type of turbo-like (TL) codes for short frame transmission. The component encoder of a TL code is a systematic feed-forward convolutional (SFC) code designed without 4-cycles and the associated component decoder uses serial belief propagation rule. TL codes are linear-time encodable and they can be decoded by belief propagation (BP) algorithms with very low complexity.