A coding technique for improving the reliability of digital transmission over noisy partial-response channels with characteristics (+or-D/sup m/), m=1, 2, where the channel input symbols are constrained to be +or-1, is presented. In particular, the application of a traditional modulation code as an inner code of a concentrated coding scheme in which the outer code is designed for maximum (free) Hamming distance is considered. A performance comparison is made between the concentrated scheme and a coding technique presented by Wolf and G. Ungerboeck (see ibid., vol. COM-34, p.765-773, Aug. 1986) for the dicode channel with transfer function (1-D). >
['Kees A. Schouhamer Immink']
Coding techniques for partial-response channels