Systems and methods for a multicarrier modulation system with a variable margin
A multicarrier modem has a plurality of carriers over which data is transmitted. By assigning, for example, one or more different margins to the individual carriers the data rate and impairment immunity can be increased.
1. A method in a multicarrier communications transceiver comprising:
transmitting a first plurality of bits on a first plurality of carriers using a first SNR (Signal to Noise Ratio) margin;
transmitting a second plurality of bits on a second plurality of carriers using a second SNR margin;
wherein the first plurality of carriers is different than the second plurality of carriers, wherein the first SNR margin is higher than the second SNR margin, and
wherein the higher first SNR margin provides more immunity to changing channel conditions than the second SNR margin,
and changing the first SNR margin value or the second SNR margin value after commencing data communications.
2. The method of claim 1 , wherein the first SNR margin specifies a first value for an increase in noise associated with the first plurality of carriers.
3. The method of claim 2 , wherein the second SNR margin specifies a second value for an increase in noise associated with the second plurality of carriers.
4. The method of claim 1 , wherein changing the first SNR margin value or the second SNR margin value is based on a time of the day.
5. The method of claim 1 , wherein changing the first SNR margin value or the second SNR margin value is based on an error rate.
6. The method of claim 1 , wherein changing the first SNR margin value or the second SNR margin value is based on a service provider directive.
7. The method of claim 1 , wherein changing the first SNR margin value or the second SNR margin value is based on a change in a quality of service requirement.
8. The method of claim 1 , wherein the first SNR margin value or the second SNR margin value is based on a loop length.
9. The method of claim 1 , wherein the first SNR margin value or the second SNR margin value is based on temperature variance information.
10. The method of claim 1 , wherein the first SNR margin value or the second SNR margin value is based on impairments on a line.
11. The method of claim 1 , wherein the first SNR margin value or the second SNR margin value is based on actual installation and historical data and/or statistical information relating to one or more carriers.
12. A multicarrier communications transceiver operable to:
transmit a first plurality of bits on a first plurality of carriers using a first SNR margin value;
transmit a second plurality of bits on a second plurality of carriers using a second SNR margin value;
wherein the first plurality of carriers is different than the second plurality of carriers,
wherein the first SNR margin value is higher than the second SNR margin value, and
wherein the higher first SNR margin value provides more immunity to changing channel conditions than the second SNR margin value,
the transceiver further operable to change the first SNR margin value or the second SNR margin value after commencing data communications.
13. The transceiver of claim 12 , wherein the first SNR margin value specifies a first value for an increase in noise associated with the first plurality of carriers.
14. The transceiver of claim 12 , wherein the second SNR margin value specifies a second value for an increase in noise associated with the second plurality of carriers.
15. The transceiver of claim 12 , wherein changing the first SNR margin value or the second SNR margin value is based on a time of the day.
16. The transceiver of claim 12 , wherein changing the first SNR margin value or the second SNR margin value is based on an error rate.
17. The transceiver of claim 12 , wherein changing the first SNR margin value or the second SNR margin value is based on a service provider directive.
18. The transceiver of claim 12 , wherein changing the first SNR margin value or the second SNR margin value is based on a change in a quality of service requirement.
19. The transceiver of claim 12 , wherein the first SNR margin value or the second SNR margin value is based on a loop length.
20. The transceiver of claim 12 , wherein the first SNR margin value or the second SNR margin value is based on temperature variance information.
21. The transceiver of claim 12 , wherein the first SNR margin value or the second SNR margin value is based on impairments on a line.
22. The transceiver of claim 12 , wherein the first SNR margin value or the second SNR margin value is based on actual installation and historical data and/or statistical information relating to one or more carriers.