Echo cancellation in a communication device
View Patent ↗According to one exemplary embodiment, a communication device comprises a line driver, where the line driver provides an output signal. The communication device further comprises a digital echo canceller module coupled to the line driver, where the digital echo canceller module receives an echo reference signal determined by the output signal of the line driver, where the echo canceller module outputs an echo cancellation signal, and where the echo cancellation signal is capable of canceling linear and non-linear components of a composite signal. The communication device further comprises a summation module coupled to the digital echo canceller module, where the summation module receives the echo cancellation signal and the composite signal, and where the composite signal comprises a received signal and the linear and non-linear echo components. The summation module is configured to subtract the echo cancellation signal from the composite signal and to output the received signal.
1. A communication device comprising:
a line driver, said line driver configured to transmit an output signal, wherein said output signal includes linear and non-linear echo components;
a first group of processing modules, said first group of processing modules receiving said output signal including said linear and non-linear echo components from said line driver, and said first group of processing modules outputting an echo reference signal based on said output signal;
a digital echo canceller module receiving said echo reference signal, said echo canceller module outputting an echo cancellation signal based on said echo reference signal for canceling said linear and non-linear echo components of a composite signal;
a second group of processing modules, said second group of processing modules receiving said output signal including said linear and non-linear echo components from said line driver, and said second group of processing modules outputting said composite signal utilizing said output signal;
a summation module coupled to said digital echo canceller module, said summation module receiving said echo cancellation signal and said composite signal, said summation module being configured to subtract said echo cancellation signal from said composite signal to cancel said linear and non-linear echo components from said composite signal.
2. The communication device of claim 1 wherein said first group of processing modules comprises a filter module.
3. The communication device of claim 1 wherein said first group of processing modules comprises an analog to digital converter module.
4. The communication device of claim 1 wherein said first group of processing modules comprises a decimation filter module.
5. The communication device of claim 1 wherein said second group of processing modules comprises a filter module.
6. The communication device of claim 1 wherein said second group of processing modules comprises an analog to digital converter module.
7. The communication device of claim 1 wherein said second group of processing modules comprises a decimation filter module.
8. The communication device of claim 1 wherein said communication device comprises a modem.
9. The communication device of claim 8 wherein said modem comprises a DSL modem.
10. A method of echo cancellation in a communication device, said method comprising steps of:
outputting a line driver output signal including linear and non-linear echo components;
receiving said output signal including said linear and non-linear echo components from said line driver using a first group of processing modules;
generating an echo reference signal based on said output signal using said first group of processing modules;
receiving said echo reference signal by a digital echo canceller module coupled to said first group of processing modules;
outputting an echo cancellation signal based on said echo cancellation signal, using said echo canceller module for canceling said linear and non-linear echo components of a composite signal;
receiving said output signal including said linear and non-linear echo components from said line driver using a second group of processing modules;
outputting said composite signal utilizing said output signal using said second group of processing modules;
subtracting said echo cancellation signal from said composite signal to cancel said linear and non-linear echo components from said composite signal.
11. The method of claim 10 wherein said communication device comprises a modem.
12. The method of claim 10 wherein said first group of processing modules comprises a filter module.
13. The method of claim 10 wherein said first group of processing modules comprises an analog to digital converter module.
14. The method of claim 10 wherein said first group of processing modules comprises a decimation filter module.
15. The method of claim 10 wherein said second group of processing modules comprises a filter module.
16. The method of claim 10 wherein said second group of processing modules comprises an analog to digital converter module.
17. The method of claim 10 wherein said second group of processing modules comprises a decimation filter module.