US Patent 7434115 Encoding and decoding apparatus and method

An interleaver and method of interleaving operate on data represented in a sequence of symbols to produce an interleaved sequence of symbols. The interleaver performs intra-block and inter-block permutations on the sequence of symbols. An encoder and method of encoding operate on data represented in a source sequence of symbols. The source sequence of symbols is encoded into a first sequence of codewords and interleaved using intra-block and inter-block permutations to produce a sequence of interleaved symbols. The sequence of interleaved symbols is encoded into a second sequence of codewords. A decoder and method of decoding operate on data represented in a sequence of received symbols. The sequence of received symbols comprises a formatted copy of the source sequence of symbols and the first and the second sequence of codewords.