Deriving the PCC iterative decoder from the SCC iterative decoder

In this paper, we show that the iterative decoder for parallel concatenated codes can be derived from the iterative decoder for serially concatenated codes. In order to show this, we use the observation that any parallel concatenated code (PCC) may be regarded as a serially concatenated code (SCC) with certain code constraints satisfied. By applying these code constraints to the SCC iterative decoder we obtain the PCC iterative decoder, and hence show that the latter can be seen as a special case of the former.