Multiple-rate channel ENDEC in a commuted read/write channel for disk storage systems

• US 6,505,320 B1
• Filed: 03/09/2000
• Issued: 01/07/2003
• Est. Priority Date: 03/09/2000
• Status: Expired due to Fees

• Current Assignee: Avago Technologies General IP PTE Limited (Broadcom, Inc.)
• Original Assignee: Cirrus Logic Incorporated
• Inventors: Zook, Christopher P., Turk, Stephen A., Vis, Marvin L.
• Primary Examiner(s): Baker, Stephen M.
• Application Number:
  US09/521,554
• Time in Patent Office: 1,034 Days
• Field of Search: 714/755, 714/769, 341/59
• US Class Current: 714/755
• CPC Class Codes: G11B 20/10055 using partial response filtering when writing the signal to the medium or reading it therefrom
• CPC Class Codes: G11B 20/1426 conversion to or from block codes or representations thereof
• CPC Class Codes: G11B 20/1833 by adding special lists or symbols to the coded information G11B20/1806, G11B20/1866 take precedence
• CPC Class Codes: G11B 2020/1434 8 to 9 modulation

Abstract

A sampled amplitude read channel is disclosed for writing data to and reading data from a disk storage medium. A first channel encoder encodes a first j-k bits of a j-bit data block to generate first encoded data, and an ECC encoder encodes the first encoded data and a remaining k-bits of the data block to generate ECC redundancy symbols comprising a plurality of bits. A second channel encoder encodes the remaining k-bits of the data block and the ECC redundancy symbols to generate second encoded data. The first encoded data and the second encoded data are then output as channel data written to the disk storage medium.

Claims

1. A commuted read/write channel for writing data to and reading data from a disk storage medium, comprising:

(a) a first channel encoder for encoding a first j-k bits of a j-bit data block to generate first encoded data;

(b) an ECC encoder for encoding the first encoded data and a remaining k-bits of the data block to generate ECC redundancy symbols comprising a plurality of bits;

(c) a second channel encoder for encoding the remaining k-bits of the data block and the ECC redundancy symbols to generate second encoded data; and

(d) an output for outputting the first encoded data and the second encoded data as channel data written to the disk storage medium.

2. The commuted read/write channel as recited in claim 1, wherein a code rate of the first channel encoder is greater than a code rate of the second channel encoder.

3. The commuted read/write channel as recited in claim 1, wherein the first channel encoder is an enumerative encoder.

4. The commuted read/write channel as recited in claim 3, wherein the enumerative encoder has a programmable code rate.

5. The commuted read/write channel as recited in claim 4, wherein:

(a) the first channel encoder encodes a first part of the j-k bits of the data block according to a first code rate of m₀/n₀; and

(b) the first channel encoder encodes a last part of the j-k bits of the data block according to a second code rate of m₁/n₁.

6. The commuted read/write channel as recited in claim 5, wherein:

(a) the first part of the j-k bits of the data block is integer divisible by m₀; and

(b) the last part of the j-k bits of the data block is integer divisible by the m₁.

7. The commuted read/write channel as recited in claim 5, wherein:

(a) the second channel encoder encodes m₂ bits of input data into n₂ bits of output data; and

(b) the bits of the ECC redundancy symbols plus the k-bits of the data block is integer divisible by m₂.

8. A method of encoding data in a commuted read/write channel for disk storage systems, comprising the steps of:

(a) first channel encoding a first j-k bits of a j-bit data block to generate first encoded data;

(b) ECC encoding the first encoded data and a remaining k-bits of the data block to generate ECC redundancy symbols comprising a plurality of bits;

(c) second channel encoding the remaining k-bits of the data block and the ECC redundancy symbols to generate second encoded data; and

(d) outputting the first encoded data and the second encoded data as channel data written to a disk storage medium.

9. The method as recited in claim 8, wherein a code rate of the first channel encoding step is greater than a code rate of the second channel encoding step.

10. The method as recited in claim 8, wherein the first channel encoding step comprises the step of enumerative encoding.

11. The method as recited in claim 10, wherein the step of enumerative encoding comprises the step of programming a code rate.

12. The method as recited in claim 11, wherein the first channel encoding step comprises the steps of:

(a) encoding a first part of the j-k bits of the data block according to a first code rate of m₀/n₀; and

(b) encoding a last part of the j-k bits of the data block according to a second code rate of m₁/n₁.

13. The method as recited in claim 12, wherein:

(a) the first part of the j-k bits of the data block is integer divisible by m₀; and

(b) the last part of the j-k bits of the data block is integer divisible by the m₁.

14. The method as recited in claim 12, wherein:

(a) the second channel encoding step comprises the step of encoding m₂ bits of input data into n₂ bits of output data; and

(b) the bits of the ECC redundancy symbols plus the k-bits of the data block is integer divisible by m₂.

15. A commuted read/write channel for transmitting data through a communication medium, comprising:

(a) a first channel encoder for encoding a first j-k bits of a j-bit data block to generate first encoded data;

(b) an ECC encoder for encoding the first encoded data and a remaining k-bits of the data block to generate ECC redundancy symbols comprising a plurality of bits;

(c) a second channel encoder for encoding the remaining k-bits of the data block and the ECC redundancy symbols to generate second encoded data; and

(d) an output for outputting the first encoded data and the second encoded data as channel data transmitted through the communication medium.

16. The commuted read/write channel as recited in claim 15, wherein a code rate of the first channel encoder is greater than a code rate of the second channel encoder.

17. The commuted read/write channel as recited in claim 15, wherein the first channel encoder is an enumerative encoder.

18. The commuted read/write channel as recited in claim 17, wherein the enumerative encoder has a programmable code rate.

19. The commuted read/write channel as recited in claim 18, wherein

(a) the first channel encoder encodes a first part of the j-k bits of the data block according to a first code rate of m₀/n₀; and

(b) the first channel encoder encodes a last part of the j-k bits of the data block according to a second code rate of m₁/n₁.

20. The commuted read/write channel as recited in claim 19, wherein:

(a) the first part of the j-k bits of the data block is integer divisible by m₀; and

(b) the last part of the j-k bits of the data block is integer divisible by m₁.

21. The commuted read/write channel as recited in claim 19, wherein:

(a) the second channel encoder encodes m₂ bits of input data into n₂ bits of output data; and

(b) the bits of the ECC redundancy symbols plus the k-bits of the data block is integer divisible by m₂.

22. A method of encoding data in a commuted read/write channel for transmitting data through a communication medium, comprising the steps of:

(a) first channel encoding a first j-k bits of a j-bit data block to generate first encoded data;

(b) ECC encoding the first encoded data and a remaining k-bits of the data block to generate ECC redundancy symbols comprising a plurality of bits;

(c) second channel encoding the remaining k-bits of the data block and the ECC redundancy symbols to generate second encoded data; and

(d) outputting the first encoded data and the second encoded data as channel data transmitted through the communication medium.

23. The method as recited in claim 22, wherein a code rate of the first channel encoding step is greater than a code rate of the second channel encoding step.

24. The method as recited in claim 22, wherein the first channel encoding step comprises the step of enumerative encoding.

25. The method as recited in claim 24, wherein the step of enumerative encoding comprises the step of programming a code rate.

26. The method as recited in claim 25, wherein the first channel encoding step comprises the steps of:

(a) encoding a first part of the j-k bits of the data block according to a first code rate of m₀/n₀; and

(b) encoding a last part of the j-k bits of the data block according to a second code rate of m₁/n₁.

27. The method as recited in claim 26, wherein:

(a) the first part of the j-k bits of the data block is integer divisible by m₀; and

(b) the last part of the j-k bits of the data block is integer divisible by the m₁.

28. The method as recited in claim 26, wherein:

(a) the second channel encoding step comprises the step of encoding m₂ bits of input data into n₂ bits of output data; and

(b) the bits of the ECC redundancy symbols plus the k-bits of the data block is integer divisible by m₂.