M-ary (d,k) runlength limited coding for multi-level data
US5781130A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 12, 1995 |
| Grant date | Jul 14, 1998 |
| Priority date | — |
| Expiry date | May 12, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L25/4917
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A system for encoding digital data with an M-ary (d,k) code to provide multi-level coded data where M>2 comprises an M-ary (d,k) encoder for accepting digital input data. The M-ary (d,k) coder encodes the digital input data to produce a plurality of code symbols, where each code symbol is at one of M levels and each pair of non-zero code symbols is separated by at least d but no more than k zeros. A waveform encoder converts the code symbols into waveform signal amplitudes compatible with a multi-level channel. Each waveform signal amplitude is generated by modulo M addition of a current code symbol with a previous waveform signal amplitude. A specific M-ary (d,k) code provides high density recording to a multi-level storage medium. The M-ary (d,k) encoder is implemented using a M-state encoder and a modulo M waveform encoder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.