| 摘要 |
Methods and apparatus are provided for modulation coding a stream of binary input data. A 4-ary enumerative encoding algorithm is applied to the input bit-stream to produce a succession of 4-ary output symbols. The 4-ary algorithm is operative to simultaneously encode respective generalized Fibonacci codes in the odd and even interleaves of the input bit-stream. The bits of each successive 4-ary output symbol are then interleaved, producing an output bit-stream which has global and interleaved run-length constraints. Inverting the bits of the 4-ary output symbols produces an output bit-stream with (G, I) -constraints as in the PRML (G, I) codes used in reverse-concatenation modulation systems. Corresponding decoding systems are also provided. |
