Claims
- 1. A method of controlling a digital communication system having a plurality of communication lines on which signals are transmitted and received, the signals being affected by interference during transmission, each of the communication lines being used by a user and having at least one transmitter and at least one receiver, the method comprising the steps of:
collecting information about line, signal and interference characteristics of the communication lines; creating a model of the line, signal and interference characteristics of the communication lines; synchronizing transmissions of signals between transmitters and receivers; processing signals using the model to remove interference from signals.
- 2. The method of claim 1 wherein the digital communication system is a DSL system.
- 3. The method of claim 1 wherein the step of processing signals using the model is performed prior to transmission of a signal.
- 4. The method of claim 1 wherein the step of processing signals using the model is performed after reception of the signals.
- 5. The method of claim 1 wherein the step of synchronizing transmissions of signals comprises using block transmission and reception.
- 6. The method of claim 1 wherein the interference affecting transmission of signals includes crosstalk from communication lines adjacent the communication line on which the signal is sent.
- 7. The method of claim 1 wherein the digital communication system uses discrete multitone transmission and the step of processing signals using the model to remove interference from signals is done on a tone by tone basis.
- 8. The method of claim 1 wherein the step of processing signals using the model to remove interference from signals comprises canceling crosstalk interference in signals by QR decomposition.
- 9. The method of claim 1 wherein the step of collecting information about line, signal and interference characteristics of the communication lines is performed by a party other than one of the users.
- 10. The method of claim 1 wherein each user is permitted to transmit and receive signals using a data rate and wherein the step of processing signals using the model to remove interference from signals comprises maximizing a weighted sum of the data rates of the users.
- 11. The method of claim 10 wherein the step of maximizing the weighted sum of the data rates of the users comprises allocating energy to each user for transmission of signals.
- 12. The method of claim 1 wherein the signals are sent using a plurality of frequencies and further wherein the step of processing signals using the model to remove interference from signals comprises dynamically adjusting the frequencies used to send the signals.
- 13. A method of controlling a digital communication system having a plurality of communication lines, each of the communication lines being used by a user, wherein the total power a user can use in the system is limited by a power constraint, the method comprising the steps of:
assigning the total power constraint for each user an initial value; determining a competitively optimal data rate for each user, comprising the steps of:
determining a power allocation within the total power constraint of each user by iteratively allowing each user to optimize its power allocation; and determining the competitively optimal data rate for each user based on the determined power allocation for the user; evaluating the competitively optimal data rate for each user, comprising the steps of:
comparing the competitively optimal data rate of a user with a target rate for the user; increasing the power constraint for a user if the competitively optimal data rate of the user is less than the target rate for the user; decreasing the power constraint for the user if the competitively optimal data rate of the user exceeds the target rate for the user by at least a prescribed variance; maintaining the power constraint for the user if the competitively optimal data rate of the user is equal to the target rate for the user; and maintaining the power constraint for the user if the competitively optimal data rate of the user exceeds the target rate for the user by less than the prescribed variance.
- 14. The method of claim 13 wherein the steps of determining a competitively optimal data rate for each user and evaluating the power constraint for each user are repeated until no power constraint is increased or decreased.
- 15. The method of claim 13 wherein the digital communication system is a DSL system.
- 16. The method of claim 13 wherein the total power allowed each user is allocated among a plurality of frequencies.
- 17. The method of claim 13 performed by a single entity.
- 18. The method of claim 13 performed by the users in a distributed fashion.
- 19. The method of claim 13 wherein crosstalk interference is injected into the communication line of a user by at least one of the lines of another user and further wherein the crosstalk interference is considered by a user in the step of determining the power allocation of the user.
- 20. The method of claim 13 wherein each user uses a modem having a power limit and wherein the power constraint of a user will not be increased to a level greater than the modem power limit irrespective of the competitively optimal data rate of the user.
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application claims the benefit of U.S. Provisional No. ______ (Attorney Docket No. STFUP018P) filed on Jun. 1, 2001, the disclosure of which is incorporated herein by reference.
Provisional Applications (1)
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Number |
Date |
Country |
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60295392 |
Jun 2001 |
US |