Multiple modulation rate 10Gbase-T transmission

• US 7,782,852 B2
• Filed: 10/11/2005
• Issued: 08/24/2010
• Est. Priority Date: 10/11/2005
• Status: Active Grant

• Current Assignee: Marvell Asia Pte Limited (Marvell Technology Group Limited)
• Original Assignee: Teranetics, Inc. (Broadcom, Inc.)
• Inventors: Tellado, Jose, Kasturia, Sanjay
• Primary Examiner(s): Nguyen; Steven H
• Assistant Examiner(s): BOKHARI, SYED M
• Application Number:
  US11/247,805
• Publication Number:
  US 20070081475A1
• Time in Patent Office: 1,778 Days
• Field of Search: 370/278, 370/277, 370/529, 370/201, 370/391, 370/333, 455/296, 455/132, 455/429, 714/758, 714/792, 379/93, 375/240, 375/219, 375/285, 369/103
• US Class Current: 370/391
• CPC Class Codes: H04L 1/0003 by switching between different modulation schemes
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0057 Block codes H04L1/0061, H04L1/0064 take precedence
• CPC Class Codes: H04L 1/007 Unequal error protection for format H04L1/0078; for codes per se H03M13/35
• CPC Class Codes: H04L 27/0008 arrangements for allowing a transmitter or receiver to use more than one type of modulation negotiating modulation type for two-way transmission paths H04L5/1453

Abstract

A device and method of high-speed transmission is disclosed. The method includes computing a signal quality of a received signal, the received signal being transmitted with a modulation order required by a default transmission modulation format. The signal quality is compared with a signal quality threshold required of the default transmission modulation format. If the signal quality is below the signal quality threshold, an indication of a level of signal quality failure is provided to a transmitter. The transmitter sets a number of un-coded bits within the transmission signal based upon the level of signal quality failure.

Claims

1. A method of high-speed transmission, comprising:

computing a signal quality of a received signal, the received signal being transmitted with a modulation order required by a default transmission modulation format;

comparing the signal quality with a signal quality threshold required of the default transmission modulation format;

if the signal quality is below the signal quality threshold, providing an indication of a level of signal quality failure to a transmitter;

the transmitter setting a number of un-coded bits within the transmission signal based upon the level of signal quality failure, while maintaining a constant number of coded bits, allowing for changes in a transmission data rate while maintaining a constant transmission symbol rate;

wherein the number of un-coded bits is 3 bits per two-dimensional modulation symbol if the signal quality is not less than the signal quality threshold, and is reduced by at least ½

bit per modulation symbol dimension if the signal quality is less than the signal quality threshold.

2. The method of claim 1, wherein the default transmission modulation format is 10GBase-T.

3. The method of claim 1, wherein transmission is initiated by a default training sequence.

4. The method of claim 1, wherein no other types of training sequences are initiated than the default training sequence.

5. The method of claim 3, wherein default training sequence is a 10GBase-T training sequence.

6. The method of claim 1, wherein the signal quality is computed by determining at least one of DPSNR, DPMSE, DPPER, BER, FER, received error pdf distribution, decision point signal to decision point cross talk ratio of the received signal.

7. The method of claim 1, wherein the number of un-coded bits is reduced by another ½

bit per modulation symbol dimension for every 3 dB the signal quality is below the signal quality threshold.

8. The method of claim 7, wherein decreasing ½

bit per modulation symbol dimension is achieved by reducing 1 bit on a two-dimensional modulation symbol.

9. The method of claim 7, wherein decreasing ½

bit per modulation symbol dimension is achieved by reducing from 2*n+1 bits on a two-dimensional modulation symbol to n bits on a one-dimensional modulation symbol.

10. The method of claim 1, wherein the number of un-coded bits is set by decreasing the number of un-coded bits from a default value by ¼

bit per modulation symbol dimension for each 1.5 dB the signal quality is below the signal quality threshold.

11. The method of claim 10, wherein decreasing % bit per modulation symbol is achieved by reducing 1 bit of a four-dimensional modulation symbol.

12. The method of claim 1, wherein the number of un-coded bits is set by decreasing the number of un-coded bits from a default value by 1 bit per modulation symbol dimension for each 6 dB the signal quality is below the signal quality threshold.

13. The method of claim 1, wherein the number of un-coded bit is increased if the signal quality is a predetermined amount greater than a threshold.

14. The method of claim 1, wherein a transmission symbol rate remains constant with changes in the number of un-coded bits.

15. The method of claim 1, wherein common analog processing circuitry, encoding circuitry, and equalizer circuitry is used with varying numbers of un-coded bits.

16. The method of claim 1, further comprising the number of un-coded bits setting a resolution of coefficients of signal processing of at least one of an equalizer, a cross-talk canceller and an echo canceller.

17. The method of claim 1, further comprising the number of un-coded bits setting a number of coefficients of signal processing of at least one of an equalizer, a cross-talk canceller and an echo canceller.

18. A method of 10GBase-T transmission, comprising:

initiating a 10GBase-T training sequence;

computing a signal quality of a received signal based upon the 10GBase-T training sequence;

comparing the signal quality with a signal quality threshold required of the 10GBase-T transmission;

if the signal quality is below the signal quality threshold, providing an indication of a level of signal quality failure to a transmitter;

the transmitter setting a number of un-coded bits within the transmission signal based upon the level of signal quality failure, while maintaining a constant number of coded bits, allowing for changes in a transmission data rate while maintaining a constant transmission symbol rate;

wherein the number of un-coded bits is 3 bits per two-dimensional modulation symbol if the signal quality is not less than the signal quality threshold, and is reduced by at least ½

bit per modulation symbol dimension if the signal quality is less than the signal quality threshold.

19. The method of claim 18, wherein a receiver computes a desired number of un-coded bits and provides the desired number to the transmitter.

20. The method of claim 18, wherein each receiver of bidirectional transmission computes a desired number of un-coded bits for the bidirectional transmission, the smallest desired number of each of both directions of the bidirectional transmission is selected for transmission in both bidirectional transmission directions.

21. The method of claim 18, wherein only 10GBase-T training sequences are initiated.

22. The method of claim 18, wherein the number of un-coded bits is reduced by another ½

bit per modulation symbol dimension for every 3 dB the signal quality is below the signal quality threshold.

23. The method of claim 18, wherein a modulation format of the transmission is DSQ128 if the signal quality not less than the signal quality threshold, the modulation format is QAM64/PAM8 if the signal quality is less than the signal quality threshold by less than 3 dB, the modulation format is QAM32/DSQ32 if the signal quality is at least 3 dB but less than 6 dB below the signal quality threshold, the modulation format is QAM16/PAM4 if the signal quality is at least 6 dB but less than 9 dB below the signal quality threshold.

24. The method of claim 18, wherein a modulation format of the transmission is PAM8 if the signal quality is less than the signal quality threshold by less than 3 dB, the modulation format is PAM4 if the signal quality is at least 3 dB but less than 9 dB.

25. The method of claim 18, wherein the number of un-coded bit is increased if the signal quality is a predetermined amount greater than a threshold.

26. The method of claim 18, further comprising the number of un-coded bits setting a resolution of bits within coefficients of signal processing of at least one of an equalizer, a cross-talk canceller and an echo canceller.

27. The method of claim 18, further comprising the number of un-coded bits setting a number of coefficients of signal processing of at least one of an equalizer, a cross-talk canceller and an echo canceller.

28. A method of 10GBase-T reception, comprising:

receiving a 10GBase-T training sequence from a 10GBase-T transmitter;

computing a signal quality of a received signal based upon the 10GBase-T training sequence;

comparing the signal quality with a signal quality threshold required of the 10GBase-T transmission;

if the signal quality is below the signal quality threshold, providing an indication of a level of signal quality failure to the transmitter, thereby setting a number of un-coded bits within transmission signals based upon the level of signal quality failure, while maintaining a constant number of coded bits, allowing for changes in a transmission data rate while maintaining a constant transmission symbol rate;

wherein the number of un-coded bits is 3 bits per two-dimensional modulation symbol if the signal quality is not less than the signal quality threshold, and is reduced by at least ½

bit per modulation symbol dimension if the signal quality is less than the signal quality threshold.

29. The method of claim 28, the receiver sets the number of un-coded bit.

30. The method of claim 28, the transmitter sets the number of un-coded bit.

31. The method of claim 28, wherein transmission is initiated by a 10GBase-T training sequence.

32. The method of claim 28, wherein no other types of training sequences are initiated than the default training sequence.

33. The method of claim 28, wherein the signal quality is computed by determining at least one of DPSNR, DPMSE, DPPER, BER, FER, error pdf distribution, decision point signal to decision point cross talk ratio of the received signal.

34. A method of 10GBase-T transmission, comprising:

transmitting a 10GBase-T training sequence;

obtaining an indication of a transmission signal quality from a receiver of the 10GBase-T training sequence, wherein the indicator of transmission signal quality providing an indication of a level of signal quality failure as compared a signal quality threshold required of the 10GBase-T transmission;

setting a number of un-coded bits within transmission signals based upon the level of signal quality failure, while maintaining a constant number of coded bits, allowing for changes in a transmission data rate while maintaining a constant transmission symbol rate;

wherein the number of un-coded bits is 3 bits per two-dimensional modulation symbol if the signal quality is not less than the signal quality threshold, and is reduced by at least ½

bit per modulation symbol dimension if the signal quality is less than the signal quality threshold.

35. The method of 10GBase-T transmission of claim 34, wherein only 10GBase-T training sequences are transmitted.

36. The method of claim 34, wherein the number of un-coded bits is reduced by another ½

bit per modulation symbol dimension for every 3 dB the signal quality is below the signal quality threshold.

37. The method of claim 34, wherein a modulation format of the transmission is DSQ128 if the signal quality not less than the signal quality threshold, the modulation format is QAM64/PAM8 if the signal quality is less than the signal quality threshold by less than 3 dB, the modulation format is QAM32/DSQ32 if the signal quality is at least 3 dB but less than 6 dB below the signal quality threshold, the modulation format is QAM16/PAM4 if the signal quality is at least 6 dB but less than 9 dB below the signal quality threshold.