Sub Graph Approach In Iterative Sum-Product Algorithm

A new scheduling algorithm to the iterative sum-product algorithm, which is called sub-graph scheduling, will be presented in this paper. The propesed algorithm provides a schedule which has a higher convergence rate than the iterative sum-product algorithm while keeping the complexity of one iteration withot degrading the performance. Our method also gives an explanation to the fact that turbo decoders have faster convergence rate than LDPC decoders.