Multi-valued scrambling and descrambling of digital data on optical disks and other storage media
Method and apparatus for writing scrambled multi-value data to a physical media and for reading scrambled multi-value data from a physical media, are disclosed. The physical media can be an optical disk. The scrambling can be performed by a multi-valued LFSR scrambler and the descrambling can be performed by a multi-valued LFSR descrambler. Further, the multi-valued data that is scrambled can include synchronization data and/or user data. Error correction coding can be used during the writing process and processing to correct for errors can be used during the reading process. Also, methods and apparatus for synchronizing multi-valued data written to and read from physical media are disclosed. Multi-value correlation methods and apparatus are also disclosed.
1. A method of storing p n-valued symbols on an optical disk with p≧1, comprising:
scrambling the p n-valued symbols, each of the p n-valued symbols having one of n states with n>2, with an n-valued scrambler implementing at least one reversible n-valued logic function by a device that processes an n-valued signal into p scrambled n-valued symbols of which each n-valued symbol has one of n states; and
writing the p scrambled n-valued symbols on the optical disk, wherein each scrambled n-valued symbol is written on the optical disk as a mark that can assume one of n states and that will generate a non-binary signal when being read.
2. The method as claimed in claim 1 , further comprising: encoding the p scrambled n-valued symbols with an error correction code.
3. The method as claimed in claim 1 , wherein the scrambling is performed by an n-valued LFSR scrambler.
4. The method as claimed in claim 3 , wherein the n-valued LFSR scrambler does not use a multiplier.
5. The method as claimed in claim 1 , wherein the scrambling is performed by an n-valued non-LFSR scrambler.
6. The method as claimed in claim 1 , further comprising: reading the p scrambled n-valued symbols from the optical disk; and descrambling the p scrambled n-valued symbols.
7. The method as claimed in claim 6 , further comprising: processing the p scrambled n-valued symbols read from the optical disk to correct possible errors in the n-valued data.
8. The method as claimed in claim 6 , wherein the descrambling is performed by an n-valued LFSR descrambler.
9. The method as claimed in claim 6 , wherein the descrambling is performed by an n-valued non-LFSR descrambler.
10. A method of reading p scrambled n-valued-symbols with n>2 and p>1 from an optical disk, comprising:
reading the p scrambled n-valued symbols from the optical disk, each of the p scrambled n-valued symbols having one of 3 or more states, each read scrambled n-valued symbol generating a non-binary signal; and
descrambling the p scrambled n-valued symbols with an n-valued descrambler implementing a reversible n-valued logic function by a device that processes an n-valued signal.
11. The method as claimed in claim 10 , further comprising: processing the p scrambled n-valued symbols read from the optical disk to correct possible errors in the p scrambled n-valued symbols.
12. The method as claimed in claim 10 , wherein the descrambling is performed by an n-valued LFSR descrambler.
13. The method as claimed in claim 12 , wherein the n-valued LFSR descrambler does not use a multiplier.
14. A method of storing and retrieving p n-valued symbols with n>2 and p>1, comprising:
scrambling the p n-valued symbols into p scrambled n-valued symbols with a scrambler implementing a reversible n-valued logic function, each n-valued symbol having one of 3 or more states; and
storing the p scrambled n-valued symbols on a data storage medium, which is an electronic medium, wherein reading a stored n-valued symbol from the data storage medium generates a non-binary signal.
15. The method as claimed in claim 14 , wherein the p n-valued symbols are scrambled by using an n-valued Linear Feedback Shift Register.
16. An apparatus for retrieving p scrambled n-state symbols with p≧1 and n>2, comprising:
a storage medium storing the p scrambled n-state symbols, wherein reading an n-state symbol from the storage medium generates a non-binary signal; and
an n-state descrambler enabled to process p n-state symbols into p descrambled n-state symbols, the n-state descrambler implementing at least one reversible n-state logic function by a device that processes a non-binary signal.
17. The apparatus as claimed in claim 16 wherein the storage medium is an optical medium.
18. The apparatus as claimed in claim 16 , wherein the storage medium is a magnetic medium.
19. The apparatus as claimed in claim 16 , wherein the storage medium is comprised of an electronic storage medium.
20. The method as claimed in claim 1 , further comprising:
storing on the optical disk a plurality of symbols to create a descrambler that includes an n-valued logic function.
21. The method as claimed in claim 10 , further comprising:
reading from the optical disk a plurality of symbols to create the n-valued descrambler.
22. The method as claimed in claim 14 , further comprising:
storing on the optical disk a plurality of symbols to create a descrambler that includes an n-valued logic function.
23. The apparatus as claimed in claim 19 , wherein the storage medium stores a plurality of symbols to create the n-state descrambler.