Claims
- 1. In a communications system employing a plurality of rate matching stages, a method of avoiding problematic Turbo code puncturing patterns, the method comprising:
(a) adjusting the number of bits punctured in each stage of rate matching; and (b) adjusting the number of bits punctured in each of the plurality of parity streams, wherein the problematic puncturing patterns are avoided.
- 2. The method of claim 1 wherein degradations in the quality of punctured error correction coded transmissions having a first group of parity 1 (P1) bits and a second group of parity 2 (P2) bits are identified, and step (b) further comprises:
(b1) adding punctured bits to the first group of P1 bits; (b2) removing punctured bits from the second group of P2 bits; and (b3) biasing the punctured rates of the P1 and P2 bits to avoid problematic puncturing patterns by:
(i) adding a number of non-punctured P1 bits to the first group; and (ii) decreasing the number of non-punctured P2 bits in the second group by the number of non-punctured P1 bits added to the first group.
- 3. The method of claim 2 further comprising:
(c) determining a number of bits {circumflex over (N)} using 18N^=⌊4I7P+12⌋wherein I is the number of bits at the input to each branch of rate matching and P is the total number of the P1 and P2 bits at the output of rate matching; and (d) if 19&LeftBracketingBar;I(P/2)-7N^2&RightBracketingBar;<1-N^2+⌊N^2⌋,calculate the bias 20Δ=⌈max{I⌊7N^-12⌋-P2,P2-I⌈7N^+12⌉}⌉,otherwise set Δ=0.
- 4. The method of claim 3, wherein non-puncturing patterns with a period of 7{circumflex over (N)}/2 cause degradation in performance results and {circumflex over (N)} is a whole number.
- 5. The method of claim 4 wherein the periods will be employed whenever the average non-puncturing period of P1 or P2 bits is within ±1 or ±{fraction (1/2)} of 7{circumflex over (N)}/2 for even and odd {circumflex over (N)} respectively.
- 6. In a communications system employing a plurality of rate matching stages, a method of avoiding problematic Turbo code puncturing patterns, the method comprising:
(a) adjusting the number of bits punctured in each stage of rate matching; and (b) adjusting the puncturing rates of each of the individual parity streams while maintaining a constant overall effective coding rate.
- 7. The method of claim 6 wherein degradations in the quality of punctured error correction coded transmissions having a first group of parity 1 (P1) bits and a second group of parity 2 (P2) bits are identified, and step (b) further comprises:
(b1) adding punctured bits to the first group of P1 bits; (b2) removing punctured bits from the second group of P2 bits; and (b3) biasing the punctured rates of the P1 and P2 bits to avoid problematic puncturing patterns by:
(i) adding a number of non-punctured P1 bits to the first group; and (ii) decreasing the number of non-punctured P2 bits in the second group by the number of non-punctured P1 bits added to the first group.
- 8. The method of claim 7 further comprising:
(c) determining a number of bits {circumflex over (N)} using 21N^=⌊4I7P+12⌋wherein I is the number of bits at the input to each branch of rate matching and P is the total number of the P1 and P2 bits at the output of rate matching; and (d) if 22&LeftBracketingBar;I(P/2)-7N^2&RightBracketingBar;<1-N^2+⌊N^2⌋,calculate the bias 23Δ=⌈max{I⌊7N^-12⌋-P2,P2-I⌈7N^+12⌉}⌉,otherwise set Δ=0.
- 9. The method of claim 8, wherein non-puncturing patterns with a period of 7{circumflex over (N)}/2 cause degradation in performance results and {circumflex over (N)} is a whole number.
- 10. The method of claim 9 wherein the periods will be employed whenever the average non-puncturing period of P1 or P2 bits is within ±1 or ±{fraction (1/2)} of 7{circumflex over (N)}/2 for even and odd {circumflex over (N)} respectively.
- 11. A method of identifying degradations in quality of punctured error correction coded transmissions, the method comprising:
(a) identifying a puncturing pattern which approximates a particular code rate; and (b) adjusting a value for anticipated degradation in accordance with the matching of the puncturing pattern and the particular code rate.
- 12. The method of claim 11 wherein degradations in the quality of punctured error correction coded transmissions having a first group of parity 1 (P1) bits and a second group of parity 2 (P2) bits are identified, and step (b) further comprises:
(b1) adding punctured bits to the first group of P1 bits; (b2) removing punctured bits from the second group of P2 bits; and (b3) biasing the punctured rates of the P1 and P2 bits to avoid problematic puncturing patterns by:
(i) adding a number of non-punctured P1 bits to the first group; and (ii) decreasing the number of non-punctured P2 bits in the second group by the number of non-punctured P1 bits added to the first group.
- 13. The method of claim 12 further comprising:
(c) determining a number of bits {circumflex over (N)} using 24N^=⌊4I7P+12⌋wherein I is the number of bits at the input to each branch of rate matching and P is the total number of the P1 and P2 bits at the output of rate matching; and (d) if 25&LeftBracketingBar;I(P/2)-7N^2&RightBracketingBar;<1-N^2+⌊N^2⌋,calculate the bias 26Δ=⌈max{I⌊7N^-12⌋-P2,P2-I⌈7N^+12⌉}⌉,otherwise set Δ=0.
- 14. The method of claim 11 further comprising:
(c) using Turbo code to implement the error correction coded transmissions.
- 15. The method of claim 14 further comprising:
(d) identifying when a non-punctured bit pattern of the transmissions exhibits a periodic characteristic, with a period equal to a period of a semi-periodic impulse response of recursive encoding blocks of the Turbo code; and (e) using the identified non-punctured bit patterns which exhibit a periodic characteristic to identify puncturing patterns with degraded performance.
- 16. A method of identifying degradations in the quality of punctured error correction coded transmissions having a first group of parity 1 (P1) bits and a second group of parity 2 (P2) bits, the method comprising:
(a) adding punctured bits to the first group of P1 bits; (b) removing punctured bits from the second group of P2 bits; and (c) biasing the punctured rates of the P1 and P2 bits to avoid problematic puncturing patterns by:
(i) adding a number of non-punctured P1 bits to the first group; and (ii) decreasing the number of non-punctured P2 bits in the second group by the number of non-punctured P1 bits added to the first group.
- 17. The method of claim 16 further comprising:
(d) using Turbo code to implement the error correction coded transmissions.
- 18. The method of claim 17 further comprising:
(e) identifying when a non-punctured bit pattern of the transmissions exhibits a periodic characteristic, with a period equal to a period of a semi-periodic impulse response of recursive encoding blocks of the Turbo code; and (f) using the identified non-punctured bit patterns which exhibit a periodic characteristic to identify puncturing patterns with degraded performance.
- 19. A method for reducing degradations in quality of punctured error corrected code transmissions, the method comprising:
(a) identifying a puncturing pattern which approximates a particular code rate; and (b) adjusting the parameters of the transmissions sufficiently to cause a mismatch in the puncturing pattern and the particular code rate.
- 20. The method of claim 19 further comprising:
(c) determining a capacity of a wireless transmit and receive unit (WTRU), including buffer sizes that are supported by the WTRU; (d) using puncturing to remove sufficient bits to fit into the buffer; and (e) adjusting an overall code rate so as to provide sufficient error correction capability, thereby providing a first rate in a first stage of puncturing and providing a second rate in a second stage of puncturing.
- 21. The method of claim 20, further comprising:
(f) increasing non-punctured bits in one of the first stage and second stage of puncturing, and decreasing non-punctured bits in another of the first stage and second stage of puncturing, thereby adding additional puncturing to one stage and removing it from the other stage.
- 22. The method of claim 20 further comprising:
(f) increasing non-punctured bits in the first stage and decreasing non-punctured bits in the second stage.
- 23. The method of claim 20 further comprising:
(f) decreasing non-punctured bits in the first stage and increasing non-punctured bits in the second stage.
- 24. The method of claim 20 further comprising:
(f) interleaving parity bits before rate matching occurs; and (g) subsequently de-interleaving the parity bits, thereby avoiding a need to periodically sample the parity bits when performing periodic sampling in rate matching, thereby mitigating the effect of the periodicity of the puncturing pattern.
- 25. A communications system for avoiding problematic Turbo code puncturing patterns, the system comprising:
(a) a plurality of rate matching stages; (b) means for adjusting the number of bits punctured in each stage of rate matching; and (c) means for adjusting the number of bits punctured in each of the plurality of parity streams, wherein the problematic puncturing patterns are avoided.
- 26. The system of claim 25 wherein degradations in the quality of punctured error correction coded transmissions having a first group of parity 1 (P1) bits and a second group of parity 2 (P2) bits are identified, the means (c) for adjusting the number of bits punctured in each of the plurality of parity streams further comprising:
(c1) means for adding punctured bits to the first group of P1 bits; (c2) means for removing punctured bits from the second group of P2 bits; and (c3) means for biasing the punctured rates of the P1 and P2 bits to avoid problematic puncturing patterns, the biasing means including:
(i) means for adding a number of non-punctured P1 bits to the first group; and (ii) means for decreasing the number of non-punctured P2 bits in the second group by the number of non-punctured P1 bits added to the first group.
- 27. The system of claim 26 further comprising:
(d) means for determining a number of bits {circumflex over (N)} using 27N^=⌊4I7P+12⌋wherein I is the number of bits at the input to each branch of rate matching and P is the total number of the P1 and P2 bits at the output of rate matching; and (e) means for calculating the bias 28Δ=⌈max{I⌊7N^-12⌋-P2,P2-I⌈7N^+12⌉}⌉if 29&LeftBracketingBar;I(P/2)-7N^2&RightBracketingBar;<1-N^2+⌊N^2⌋;and (e) means for setting bias 30Δ=0 if &LeftBracketingBar;I(P/2)-7N^2&RightBracketingBar;≥1-N^2+⌊N^2⌋.
- 28. The system of claim 27, wherein non-puncturing patterns with a period of 7{circumflex over (N)}/2 cause degradation in performance results and {circumflex over (N)} is a whole number.
- 29. The system of claim 28 wherein the periods will be employed whenever the average non-puncturing period of P1 or P2 bits is within ±1 or ±{fraction (1/2)} of 7{circumflex over (N)}/2 for even and odd {circumflex over (N)} respectively.
- 30. A communications system for avoiding problematic Turbo code puncturing patterns, the system comprising:
(a) a plurality of rate matching stages; (b) means for adjusting the number of bits punctured in each stage of rate matching; and (c) means for adjusting the puncturing rates of each of the individual parity streams while maintaining a constant overall effective coding rate.
- 31. The system of claim 30 wherein degradations in the quality of punctured error correction coded transmissions having a first group of parity 1 (P1) bits and a second group of parity 2 (P2) bits are identified, the means (c) for adjusting the puncturing rates of each of the individual parity streams further comprising:
(c1) means for adding punctured bits to the first group of P1 bits; (c2) means for removing punctured bits from the second group of P2 bits; and (c3) means for biasing the punctured rates of the P1 and P2 bits to avoid problematic puncturing patterns, the biasing means (c3) including:
(i) means for adding a number of non-punctured P1 bits to the first group; and (ii) means for decreasing the number of non-punctured P2 bits in the second group by the number of non-punctured P1 bits added to the first group.
- 32. The system of claim 31 further comprising:
(d) means for determining a number of bits {circumflex over (N)} using 31N^=⌊4I7P+12⌋wherein I is the number of bits at the input to each branch of rate matching and P is the total number of the P1 and P2 bits at the output of rate matching; (e) means for calculating the bias 32Δ=⌈max{I⌊7N^-12⌋-P2,P2-I⌈7N^+12⌉}⌉if 33&LeftBracketingBar;I(P/2)-7N^2&RightBracketingBar;<1-N^2+⌊N^2⌋;and (e) means for setting bias. 34Δ=0 if &LeftBracketingBar;I(P/2)-7N^2&RightBracketingBar;≥1-N^2+⌊N^2⌋.
- 33. The system of claim 32, wherein non-puncturing patterns with a period of 7{circumflex over (N)}/2 cause degradation in performance results and {circumflex over (N)} is a whole number.
- 34. The system of claim 33 wherein the periods will be employed whenever the average non-puncturing period of P1 or P2 bits is within ±1 or ±{fraction (1/2)} of 7{circumflex over (N)}/2 for even and odd {circumflex over (N)} respectively.
- 35. A communications system for identifying degradations in quality of punctured error correction coded transmissions, the system comprising:
(a) means for identifying a puncturing pattern which approximates a particular code rate; and (b) means for adjusting a value for anticipated degradation in accordance with the matching of the puncturing pattern and the particular code rate.
- 36. The system of claim 35 wherein degradations in the quality of punctured error correction coded transmissions having a first group of parity 1 (P1) bits and a second group of parity 2 (P2) bits are identified, the means (b) for adjusting a value for anticipated degradation further comprising:
(b1) means for adding punctured bits to the first group of P1 bits; (b2) means for removing punctured bits from the second group of P2 bits; and (b3) means for biasing the punctured rates of the P1 and P2 bits to avoid problematic puncturing patterns, the biasing means (b3) including:
(i) means for adding a number of non-punctured P1 bits to the first group; and (ii) means for decreasing the number of non-punctured P2 bits in the second group by the number of non-punctured P1 bits added to the first group.
- 37. The system of claim 36 further comprising:
(c) means for determining a number of bits {circumflex over (N)} using 35N^=⌊4I7P+12⌋wherein I is the number of bits at the input to each branch of rate matching and P is the total number of the P1 and P2 bits at the output of rate matching; (d) means for calculating the bias 36Δ=⌈max{I⌊7N^-12⌋-P2,P2-I⌈7N^+12⌉}⌉if 37&LeftBracketingBar;I(P/2)-7N^2&RightBracketingBar;<1-N^2+⌊N^2⌋;and (e) means for setting bias. 38Δ=0 if &LeftBracketingBar;I(P/2)-7N^2&RightBracketingBar;≥1-N^2+⌊N^2⌋.
- 38. The system of claim 35 further comprising:
(c) means for using Turbo code to implement the error correction coded transmissions.
- 39. The system of claim 38 further comprising:
(d) means for identifying when a non-punctured bit pattern of the transmissions exhibits a periodic characteristic, with a period equal to a period of a semi-periodic impulse response of recursive encoding blocks of the Turbo code; and (e) means for using the identified non-punctured bit patterns which exhibit a periodic characteristic to identify puncturing patterns with degraded performance.
- 40. A communications system for identifying degradations in the quality of punctured error correction coded transmissions having a first group of parity 1 (P1) bits and a second group of parity 2 (P2) bits, the system comprising:
(a) means for adding punctured bits to the first group of P1 bits; (b) means for removing punctured bits from the second group of P2 bits; and (c) means for biasing the punctured rates of the P1 and P2 bits to avoid problematic puncturing patterns, the biasing means (c) including:
(i) means for adding a number of non-punctured P1 bits to the first group; and (ii) means for decreasing the number of non-punctured P2 bits in the second group by the number of non-punctured P1 bits added to the first group.
- 41. The system of claim 40 further comprising:
(d) means for using Turbo code to implement the error correction coded transmissions.
- 42. The system of claim 41 further comprising:
(e) means for identifying when a non-punctured bit pattern of the transmissions exhibits a periodic characteristic, with a period equal to a period of a semi-periodic impulse response of recursive encoding blocks of the Turbo code; and (f) means for using the identified non-punctured bit patterns which exhibit a periodic characteristic to identify puncturing patterns with degraded performance.
- 43. A communications system for reducing degradations in quality of punctured error corrected code transmissions, the system comprising:
(a) means for identifying a puncturing pattern which approximates a particular code rate; and (b) means for adjusting the parameters of the transmissions sufficiently to cause a mismatch in the puncturing pattern and the particular code rate.
- 44. The system of claim 43 further comprising:
(c) means for determining a capacity of a wireless transmit and receive unit (WTRU), including buffer sizes that are supported by the WTRU; (d) means for using puncturing to remove sufficient bits to fit into the buffer; and (e) means for adjusting an overall code rate so as to provide sufficient error correction capability, thereby providing a first rate in a first stage of puncturing and providing a second rate in a second stage of puncturing.
- 45. The system of claim 44, further comprising:
(f) means for increasing non-punctured bits in one of the first stage and second stage of puncturing, and decreasing non-punctured bits in another of the first stage and second stage of puncturing, thereby adding additional puncturing to one stage and removing it from the other stage.
- 46. The system of claim 44 further comprising:
(f) means for increasing non-punctured bits in the first stage and decreasing non-punctured bits in the second stage.
- 47. The system of claim 44 further comprising:
(f) means for decreasing non-punctured bits in the first stage and increasing non-punctured bits in the second stage.
- 48. The system of claim 44 further comprising:
(f) means for interleaving parity bits before rate matching occurs; and (g) means for subsequently de-interleaving the parity bits, thereby avoiding a need to periodically sample the parity bits when performing periodic sampling in rate matching, thereby mitigating the effect of the periodicity of the puncturing pattern.
CROSS REFERENCE TO RELATED APPLICATION(S)
[0001] This application claims priority from U.S. Provisional Patent Applications Serial No.60/434,232, filed Dec. 16, 2002, Serial No.60/444,068, filed on Jan. 30, 2003, Serial No. 60/470,921, filed on May 15, 2003, and Serial No. 60/494,404 filed on Aug. 11, 2003.
Provisional Applications (4)
|
Number |
Date |
Country |
|
60434232 |
Dec 2002 |
US |
|
60444068 |
Jan 2003 |
US |
|
60470921 |
May 2003 |
US |
|
60494404 |
Aug 2003 |
US |