Performance analysis and optimization of concatenated block-turbo coding schemes

In this paper, a concatenated coding scheme consisting of an outer algebraic block code performing hard decoding connected to an inner turbo code through a rectangular interleaver is analyzed. The performance of the concatenated code is evaluated through a semi-analytical approach, based on the expression of the word error probability at the output of the outer decoder as a function of the error statistics at the output of the turbo decoder estimated through simulation. The proposed technique yields results that depend on the size of the interleaver, and permits to obtain trade-offs between that size and the outer code characteristics.