Modulation coding with RLL (1, k) and MTR (2) constraints

摘要

This invention relates to a method of converting a user bitstream into a coded bitstream by means of a runlengh limited (d, k) channel code where the channel code has a constraint of d=1. In order to ensure an improvement in bit detection performance an additional RMTR constraint of r=2 is imposed limiting to two the maximum number of minimum runs allowed by the d=1 constraint. An additional advantage of such a code is a limitation of the back-tracking depth of a Viterbi bit-detector Based on two different k constraints the construction of such d=1 and r=2 codes is disclosed.