One can have a decoder where one user probabilistic decoding in terms of MAP and, since the data have been interleaver one uses a mechanism to see that, there are more than one decoder and the interconnection of them gives you in some way error correction. It has been shown that this kind of decoder gives you error correcting capability and the bound which it gives you is almost close to the Shannon bound. The turbo code performs very close to Shannon bound and it is now getting implemented in hardware, and when it is implemented in hardware, it will have impact on mobile communication because, as we have seen, turbo code is close to Shannon bound only by point 7 dB.

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