M=5 (0,2) runlength limited code for multi-level data
US5659310A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 12, 1995 |
| Grant date | Aug 19, 1997 |
| Priority date | — |
| Expiry date | May 12, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03M5/20
- WIPO fieldBasic communication processes
- 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=5 (0,2) code provides high density recording to a multi-level storage medium. The M=5 (0,2) encoder is implemented using a three-state encoder and a modulo five waveform encoder.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.