Method and apparatus for processing digital signals prior to recording
US4851837A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 12, 1986 |
| Grant date | Jul 25, 1989 |
| Priority date | — |
| Expiry date | May 12, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B20/1426
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method of processing digital information prior to recording comprises converting input digital words into code words, each of the same period as the input digital word but containing a greater number of time slots than the number of bit locations in the digital word, providing a plurality of groups of code words and selecting the group from which a code word will be taken in any instance on the basis of the immediately preceding code word. The code words are defined such that there is a minimum spacing of three time slots between transitions and no transition is permitted in the last time slot. Two main groups of code words are provided which each have a transformed version. Apparatus for carrying out the method as described as is apparatus for decoding the encode words in replay.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.