Chase iteration processing for decoding input data

• US 6,460,160 B1
• Filed: 02/14/2000
• Issued: 10/01/2002
• Est. Priority Date: 02/14/2000
• Status: Expired due to Fees

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Classon, Brian Keith
• Primary Examiner(s): Decady, Albert
• Assistant Examiner(s): Chase, Shelly A
• Application Number:
  US09/503,761
• Time in Patent Office: 960 Days
• Field of Search: 714/751-752, 714/780, 714/782, 714/790-791
• US Class Current: 714/791
• CPC Class Codes: H03M 13/2957 Turbo codes and decoding
• CPC Class Codes: H03M 13/453 wherein the candidate code words are obtained by an algebraic decoder, e.g. Chase decoding

Abstract

System includes decoder. Decoder performs a portion of an intermediate Chase iteration, of a series of Chase iterations for decoding input data, to obtain a successful hard-decision decoding result for input data. Decoder determines that the successful hard-decision decoding result comprises overall Chase decoding result, for the series of Chase iterations, with employment of reliability information for at least one location of input data and without employment of information that specifies, for input data, error location within input data. The intermediate Chase iteration and a Chase iteration comprise consecutive Chase iterations having only one value difference between respective code patterns thereof. Decoder skips at least one intermediate Chase iteration to proceed to the intermediate Chase iteration that obtains the successful hard-decision decoding result.

Claims

1. A method for determining an overall Chase decoding result for a series of Chase iterations for decoding input data, the method comprising the steps of:

performing a portion of an intermediate Chase iteration of the series of Chase iterations to obtain a successful hard-decision decoding result for the input data;

determining that the successful hard-decision decoding result comprises the overall Chase decoding result with employment of reliability information for at least one location of the input data and without employment of information that specifies, for the input data, error location within the input data; and

wherein the step of performing a portion of the intermediate Chase iteration of the series of Chase iterations to obtain the successful hard-decision decoding result for the input data comprises the step of selecting the intermediate Chase iteration and a Chase iteration of the series of Chase iterations to comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations.

2. The method of claim 1 wherein the intermediate Chase iteration comprises a second intermediate Chase iteration of the series of Chase iterations, and herein the step of performing a portion of the second intermediate Chase iteration of the series of Chase iterations to obtain the successful hard-decision decoding result for the input data comprises the step of skipping at least one first intermediate Chase iteration of the series of Chase iterations to proceed to the second intermediate Chase iteration.

3. A system for determining an overall Chase decoding result for a series of Chase iterations for decoding input data, the system comprising:

a decoder that performs a portion of an intermediate Chase iteration of the series of Chase iterations to obtain a successful hard-decision decoding result for the input data;

wherein the decoder determines that the successful hard-decision decoding result comprises the overall Chase decoding result with employment of reliability information for at least one location of the input data and without employment of information that specifies, for the input data, error location within the input data; and

wherein the intermediate Chase iteration and a Chase iteration of the series of Chase iterations comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations.

4. The system of claim 3 wherein the intermediate Chase iteration comprises a second intermediate Chase iteration of the series of Chase iterations, and wherein the decoder skips at least one first intermediate Chase iteration of the series of Chase iterations to proceed to the second intermediate Chase iteration.

5. An article of manufacture, comprising:

at least one computer usable medium having computer readable program code means embodied therein for causing determination of an overall Chase decoding result for a series of Chase iterations for decoding input data, the computer readable program code means in the article of manufacture comprising;

computer readable program code means for causing a computer to perform a portion of an intermediate Chase iteration of the series of Chase iterations to obtain a successful hard-decision decoding result for the input data; and

computer readable program code means for causing a computer to determine that the successful hard-decision decoding result comprises the overall Chase decoding result with employment of reliability information for at least one location of the input data and without employment of information that specifies, for the input data, error location within the input data.

6. The article of manufacture of claim 5 wherein the computer readable program code means for causing a computer to perform a portion of the intermediate Chase iteration of the series of Chase iterations to obtain the successful hard-decision decoding result for the input data comprises means for causing a computer to select the intermediate Chase iteration and a Chase iteration of the series of Chase iterations to comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations.

7. The article of manufacture of claim 5 wherein the intermediate Chase iteration comprises a second intermediate Chase iteration of the series of Chase iterations, and wherein the computer readable program code means for causing a computer to perform a portion of the second intermediate Chase iteration of the series of Chase iterations to obtain the successful hard-decision decoding result for the input data comprises means for causing a computer to skip at least one first intermediate Chase iteration of the series of Chase iterations to proceed to the second intermediate Chase iteration.

8. A method for performing a plurality of Chase iterations of a series of Chase iterations for decoding input data, the method comprising the steps of:

employing a first code pattern to perform a first Chase iteration of the plurality of Chase iterations; and

employing a second code pattern to perform a second Chase iteration of the plurality of Chase iterations;

wherein the first and second Chase iterations comprise consecutive Chase iterations of the series of Chase iterations;

wherein only one value difference exists between the first and second code patterns.

9. The method of claim 8 wherein the step of employing the second code pattern to perform the second Chase iteration of the plurality of Chase iterations comprises the steps of:

selecting the second Chase iteration to comprise an intermediate Chase iteration of the series of Chase iterations;

performing a portion of the second Chase iteration to obtain a successful hard-decision decoding result for the input data; and

determining that the successful hard-decision decoding result comprises an overall Chase decoding result for the series of Chase iterations.

10. The method of claim 8 wherein the plurality of chase iterations occurs within a soft-output Chase decoder that serves to decode constituent block codes of a block turbo code.

11. A system for performing a plurality of Chase iterations of a series of Chase iterations for decoding input data, the system comprising:

a decoder that employs a first code pattern to perform a first Chase iteration of the plurality of Chase iterations;

wherein the decoder employs a second code pattern to perform a second Chase iteration of the plurality of Chase iterations;

wherein the first and second Chase iterations comprise consecutive Chase iterations of the series of Chase iterations;

wherein only one value difference exists between the first and second code patterns.

12. The system of claim 11 wherein the second Chase iteration comprises an intermediate Chase iteration of the series of Chase iterations, wherein the decoder performs a portion of the second Chase iteration to obtain a successful hard-decision decoding result for the input data, and wherein the decoder determines that the successful hard-decision decoding result comprises an overall Chase decoding result for the series of Chase iterations.

13. The system of claim 11 wherein the decoder skips at least one intermediate Chase iteration of the series of Chase iterations to proceed to the second Chase iteration.

14. An article of manufacture, comprising:

at least one computer usable medium having computer readable program code means embodied therein for causing performance of a plurality of Chase iterations of a series of Chase iterations for decoding input data, the computer readable program code means in the article of manufacture comprising;

computer readable program code means for causing a computer to employ a first code pattern to perform a first Chase iteration of the plurality of Chase iterations; and

computer readable program code means for causing a computer to employ a second code pattern to perform a second Chase iteration of the plurality of Chase iterations;

wherein the first and second Chase iterations comprise consecutive Chase iterations of the series of Chase iterations;

wherein only one value difference exists between the first and second code patterns.

15. The article of manufacture of claim 14 wherein the computer readable program code means for causing a computer to employ the second code pattern to perform the second Chase iteration of the plurality of Chase iterations comprises:

computer readable program code means for causing a computer to select the second Chase iteration to comprise an intermediate Chase iteration of the series of Chase iterations;

computer readable program code means for causing a computer to perform a portion of the second Chase iteration to obtain a successful hard-decision decoding result for the input data; and

computer readable program code means for causing a computer to determine that the successful hard-decision decoding result comprises an overall Chase decoding result for the series of Chase iterations.

16. The article of manufacture of claim 14 wherein the computer readable program code means for causing a computer to employ the second code pattern to perform the second Chase iteration of the plurality of Chase iterations comprises computer readable program code means for causing a computer to skip at least one intermediate Chase iteration of the series of Chase iterations to proceed to the second Chase iteration.

17. A method for processing a plurality of Chase iterations of a series of Chase iterations for decoding input data, the method comprising the steps of:

performing a first Chase iteration of the series of Chase iterations to obtain a successful hard-decision decoding result for the input data; and

skipping at least one intermediate Chase iteration of the series of Chase iterations to proceed to a second Chase iteration of the series of Chase iterations;

wherein the first Chase iteration and a Chase iteration of the at least one intermediate Chase iteration comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations;

wherein a Chase iteration of the at least one intermediate Chase iteration and the second Chase iteration comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations.

18. The method of claim 17 wherein the step of skipping the at least one intermediate Chase iteration of the series of Chase iterations to proceed to the second Chase iteration of the series of Chase iterations comprises the step of selecting the second Chase iteration to comprise an intermediate Chase iteration of the series of Chase iterations.

19. The method of claim 17 wherein the step of performing the first Chase iteration of the series of Chase iterations to obtain the successful hard-decision decoding result for the input data and the step of skipping the at least one intermediate Chase iteration of the series of Chase iterations to proceed to the second Chase iteration of the series of Chase iterations comprise the steps of:

selecting the first Chase iteration and a selected Chase iteration of the at least one intermediate Chase iteration to comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations; and

selecting the selected Chase iteration and the second Chase iteration to comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations.

20. The method of claim 17 wherein the step of skipping the at least one intermediate Chase iteration of the series of Chase iterations to proceed to the second Chase iteration of the series of Chase iterations comprises the step of selecting each set of consecutive Chase iterations, of the at least one intermediate Chase iteration, to comprise consecutive Chase iterations having only one value difference between respective code patterns thereof.

21. The method of claim 17 wherein the step of skipping the at least one intermediate Chase iteration of the series of Chase iterations to proceed to the second Chase iteration of the series of Chase iterations comprises the step of selecting the at least one intermediate Chase iteration to comprise a plurality of intermediate Chase iterations of the series of Chase iterations.

22. The method of claim 17 wherein the step of skipping the at least one intermediate Chase iteration of the series of Chase iterations to proceed to the second Chase iteration of the series of Chase iterations comprises the steps of:

selecting the second Chase iteration to comprise an intermediate Chase iteration of the series of Chase iterations;

performing a portion of the second Chase iteration to obtain a second successful hard-decision decoding result for the input data; and

determining that the second successful hard-decision decoding result comprises an overall Chase decoding result for the series of Chase iterations.

23. A system for processing a plurality of Chase iterations of a series of Chase iterations for decoding input data, the system comprising:

a decoder that performs a first Chase iteration of the series of Chase iterations to obtain a successful hard-decision decoding result for the input data;

wherein the decoder skips at least one intermediate Chase iteration of the series of Chase iterations to proceed to a second Chase iteration of the series of Chase iterations;

wherein the first Chase iteration and a Chase iteration of the at least one intermediate Chase iteration comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations;

wherein a Chase iteration of the at least one intermediate Chase iteration and the second Chase iteration comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations.

24. The system of claim 23 wherein the second Chase iteration comprises an intermediate Chase iteration of the series of Chase iterations.

25. The system of claim 23 wherein the first Chase iteration and a selected Chase iteration of the at least one intermediate Chase iteration comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations;

and

wherein the selected Chase iteration and the second Chase iteration comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations.

26. The system of claim 23 wherein each set of consecutive Chase iterations, of the at least one intermediate Chase iteration, comprises consecutive Chase iterations having only one value difference between respective code patterns thereof.

27. The system of claim 23 wherein the at least one intermediate Chase iteration comprises a plurality of intermediate Chase iterations of the series of Chase iterations.

28. The system of claim 23 wherein the second Chase iteration comprises an intermediate Chase iteration of the series of Chase iterations;

wherein the decoder performs a portion of the second Chase iteration to obtain a second successful hard-decision decoding result for the input data; and

wherein the decoder determines that the second successful hard-decision decoding result comprises an overall Chase decoding result for the series of Chase iterations.

29. An article of manufacture, comprising:

at least one computer usable medium having computer readable program code means embodied therein for causing processing of a plurality of Chase iterations of a series of Chase iterations for decoding input data, the computer readable program code means in the article of manufacture comprising;

computer readable program code means for causing a computer to perform a first Chase iteration of the series of Chase iterations to obtain a successful hard-decision decoding result for the input data; and

computer readable program code means for causing a computer to skip at least one intermediate Chase iteration of the series of Chase iterations to proceed to a second Chase iteration of the series of Chase iterations;

wherein the first Chase iteration and a Chase iteration of the at least one intermediate Chase iteration comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations;

wherein a Chase iteration of the at least one intermediate Chase iteration and the second Chase iteration comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations.

30. The article of manufacture of claim 29 wherein the computer readable program code means for causing a computer to skip the at least one intermediate Chase iteration of the series of Chase iterations to proceed to the second Chase iteration of the series of Chase iterations comprises computer readable program code means for causing a computer to select the second Chase iteration to comprise an intermediate Chase iteration of the series of Chase iterations.

31. The article of manufacture of claim 29 wherein the computer readable program code means for causing a computer to perform the first Chase iteration of the series of Chase iterations to obtain the successful hard-decision decoding result for the input data and the computer readable program code means for causing a computer to skip the at least one intermediate Chase iteration of the series of Chase iterations to proceed to the second Chase iteration of the series of Chase iterations comprise:

computer readable program code means for causing a computer to select the first Chase iteration and a selected Chase iteration of the at least one intermediate Chase iteration to comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations; and

computer readable program code means for causing a computer to select the selected Chase iteration and the second Chase iteration to comprise consecutive Chase iterations, having only one value difference between respective code patterns thereof, of the series of Chase iterations.

32. The article of manufacture of claim 29 wherein the computer readable program code means for causing a computer to skip the at least one intermediate Chase iteration of the series of Chase iterations to proceed to the second Chase iteration of the series of Chase iterations comprises computer readable program code means for causing a computer to select each set of consecutive Chase iterations, of the at least one intermediate Chase iteration, to comprise consecutive Chase iterations having only one value difference between respective code patterns thereof.

33. The article of manufacture of claim 29 wherein the computer readable program code means for causing a computer to skip the at least one intermediate Chase iteration of the series of Chase iterations to proceed to the second Chase iteration of the series of Chase iterations comprises computer readable program code means for causing a computer to select the at least one intermediate Chase iteration to comprise a plurality of intermediate Chase iterations of the series of Chase iterations.

34. The article of manufacture of claim 31 wherein the computer readable program code means for causing a computer to skip the at least one intermediate Chase iteration of the series of Chase iterations to proceed to the second Chase iteration of the series of Chase iterations comprises:

computer readable program code means for causing a computer to select the second Chase iteration to comprise an intermediate Chase iteration of the series of Chase iterations;

computer readable program code means for causing a computer to perform a portion of the second Chase iteration to obtain a second successful hard-decision decoding result for the input data; and

computer readable program code means for causing a computer to determine that the second successful hard-decision decoding result comprises an overall Chase decoding result for the series of Chase iterations.