Hierarchical trellis coded modulation

• US 8,418,018 B2
• Filed: 09/24/2009
• Issued: 04/09/2013
• Est. Priority Date: 10/24/2003
• Status: Expired due to Fees

• Current Assignee: Ikanos Communications Incorporated (Qualcomm, Inc.)
• Original Assignee: Ikanos Communications Incorporated (Qualcomm, Inc.)
• Inventors: Pons, Julien, Duvaut, Patrick, Moreno, Oliver, Pierrugues, Laurent
• Primary Examiner(s): Baderman, Scott
• Assistant Examiner(s): Arcos, Jeison C
• Application Number:
  US12/565,939
• Publication Number:
  US 20100017678A1
• Time in Patent Office: 1,293 Days
• Field of Search: 714/758, 714/784, 375/261, 375/298
• US Class Current: 714/752
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0045 Arrangements at the receiver end
• CPC Class Codes: H04L 1/006 Trellis-coded modulation
• CPC Class Codes: H04L 1/0066 Parallel concatenated codes
• CPC Class Codes: H04L 1/007 Unequal error protection for format H04L1/0078; for codes per se H03M13/35
• CPC Class Codes: H04L 1/208 involving signal re-encoding
• CPC Class Codes: H04L 27/3416 in which the information is carried by both the individual signal points and the subset to which the individual points belong, e.g. using coset coding, lattice coding, or related schemes

Abstract

A system and method for encoding information is disclosed. In one embodiment, information is encoded using a high protection code for the least significant bit and a low protection code for the next three most significant bits. The remaining bits are uncoded. The high protection code may be a turbo code and the low protection code may be a trellis coded modulation code. In this embodiment, the collection of bits is then mapped according to a diagonally shifted QAM constellation technique.

Claims

1. A method for decoding a quantity of coded electronic information, the method comprising:

at least partially decoding the quantity of coded information using a high protection code decoder to produce an estimated information bit;

re-encoding the estimated information bit for a next decoding stage to be performed; and

at least partially decoding the re-encoded estimated information bit using a low protection code decoder to produce an estimation of a vector to be transmitted.

2. The method of claim 1 wherein the high protection code is selected from the group consisting of:

a turbo code and a low-density parity-check code.

3. The method of claim 1 wherein the quantity of coded information comprises information coded by a coding method, the coding method including encoding according to the high protection code, wherein the high protection code does not limit the asymptotic performance of the coding method.

4. The method of claim 1 wherein the quantity of information is present on a signal comprising a 4D lattice-type signal set.

5. The method of claim 1 wherein the low protection code comprises trellis coded modulation.

6. The method of claim 1 wherein the low protection code comprises a Wei code.

7. The method of claim 6 wherein the Wei code is consistent with ITU G.992.1 standard.

8. The method of claim 1 wherein the quantity of coded information comprises ADSL information.

9. The method of claim 1 further comprising passing a probability from the high protection code decoder to the low protection code decoder.

10. A system for decoding a quantity of coded electronic information, the system comprising:

a high protection code decoder configured to at least partially decode the quantity of information to produce an estimated information bit;

a re-encoder configured to re-encode the estimated information bit for a next decoding stage to be performed; and

a low protection code decoder configured to at least partially decode the re-encoded estimated information bit to produce an estimation of a vector to be transmitted.

11. The system of claim 10 wherein the high protection code decoder is selected from the group consisting of:

a turbo code decoder and a low-density parity-check code decoder.

12. The system of claim 10 wherein the system is configured to accept information encoded by an encoding system comprising a high protection code encoder, wherein the high protection code encoder does not limit the asymptotic performance of the encoding system.

13. The system of claim 10 wherein the quantity of information is present on a signal comprising a 4D lattice-type signal set.

14. The system of claim 10 wherein the low protection code decoder is configured to decode trellis coded modulation information.

15. The system of claim 10 wherein the low protection code decoder comprises a Wei decoder.

16. The system of claim 15 wherein the Wei decoder is consistent with ITU G.992.1 standard.

17. The system of claim 10 configured to decode ADSL information.

18. The system of claim 10 wherein the high protection code decoder is configured to pass a probability to the low protection code decoder.

19. A method for decoding electronic information comprising:

decoding a first part of the electronic information encoded with a first code using a first decoder to obtain an estimated information bit, wherein the first code does not affect asymptotic performance of the method;

re-encoding the estimated information bit for a second decoding stage to be performed; and

decoding a second part of the electronic information encoded with a second code using a second decoder to produce an estimated vector to be transmitted, wherein the second code has a different degree of error protection than the first code.

20. The method of claim 19, wherein the first code has a greater degree of error protection than the second code.

21. The method of claim 19, wherein the re-encoded estimated information bit is combined with the information decoded at the second decoder.

22. The method of claim 19, wherein the first decoder is configured to pass a probability to the second decoder.

23. The method of claim 19, wherein the first code comprises a turbo code or a low-density parity-check code.

24. The method of claim 19, wherein the second code comprises a trellis coded modulation code or a Wei code.

25. The method of claim 19, wherein the first part of the electronic information is a least significant bit of the electronic information.

26. The method of claim 25, wherein the second part of the electronic information is a next three significant bits of the electronic information.

27. A system for decoding electronic information comprising:

a first decoding stage to decode a first part of the electronic information encoded with a first code to obtain an estimated information bit, wherein the first code does not affect asymptotic performance of the method;

a re-encoding stage configured to re-encode the estimated information bit for a second decoding stage to be performed; and

the second decoding stage to decode a second part of the electronic information encoded with a second code to produce an estimated vector to be transmitted, wherein the second code has a different degree of error protection than the first code.

28. The system of claim 27, wherein the first code has a greater degree of error protection than the second code.

29. The system of claim 27, wherein the re-encoded estimated information bit is combined with the information decoded at the second decoding stage.

30. The system of claim 27, wherein the first decoding stage is configured to pass a probability to the second decoding stage.

31. The system of claim 27, wherein the first code comprises a turbo code or a low-density parity-check code.

32. The system of claim 27, wherein the second code comprises a trellis coded modulation code or a Wei code.

33. The system of claim 27, wherein the first part of the electronic information is a least significant bit of the electronic information.

34. The system of claim 33, wherein the second part of the electronic information is a next three significant bits of the electronic information.