F UTURE W ORK

Up to now, the early termination scheme is regarded as the most efficient way to reduce the power consumption in turbo decoders. It uses several characteristics in turbo decoding to judge if decoding sequence is nearly correct before maximum iteration number is achieved.

Once iterative decoding can be stopped earlier, then the power can be saved. In [37], an iteration stopping criterion has been modified based on the cross entropy between the a posteriori probabilities of two SISO decoders for each iteration. Some other simplified criteria was proposed in [38] and [39]. Most of these criteria make the decoder idle for saving power. The idea of utilization mentioned in chapter 4 will be useful for thinking of a new stopping criterion, which should be more precisely called “skipping criterion.” If we set a

“skipping criterion” for all sub-codewords in our proposed intra-codeword parallel architecture, the decoder will skip decoding certain sub-codewords which is meet the

“skipping criterion.” Therefore, the decoding procedure would be more efficient and the throughput will increase as the channel condition going better.

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