Tranceiver non-linearity cancellation
View Patent ↗Embodiments of a method and apparatus for reducing non-linear transmit signal components of a receive signal of a transceiver signal are disclosed. The method includes the transceiver simultaneously transmitting a transmit signal, and receiving the receive signal. A non-linear replica signal of non-linear transmission signal components that are created in the transceiver by a transmit signal DAC, and imposed onto the receive signal, is generated. The non-linear replica signal is subtracted from the received signal reducing the non-linear transmission signal components imposed onto the receive signal.
1. A method of reducing non-linear transmit signal components of a receive signal of a transceiver, the method comprising:
the transceiver simultaneously transmitting a transmit signal, and receiving the receive signal;
generating a non-linear replica signal of non-linear transmission signal components that are created in the transceiver by a transmit signal digital-to-analog converter (DAC), and imposed onto the receive signal, wherein generating the non-linear replica signal comprises non-linear filtering of the transmit signal, wherein the non-linear filtering comprises linear combinations of regressors, wherein each coefficient of a non-linear filter that performs the non-linear filtering is generated based on correlating an output of a receiver analog-to-digital-converter (ADC) with an output of a corresponding regressor within the non-linear filter;
combining the non-linear replica signal with the received signal.
2. A method of reducing non-linear transmit signal components of a receive signal of a transceiver, the method comprising:
the transceiver simultaneously transmitting a transmit signal, and receiving the receive signal;
generating a non-linear replica signal of non-linear transmission signal components that are created in the transceiver by a transmit signal digital-to-analog converter (DAC), and imposed onto the receive signal, wherein generating the non-linear replica signal comprises non-linear filtering the transmit signal and an estimated echo signal, wherein the non-linear filtering comprises linear combinations of regressors, wherein each coefficient of a non-linear filter that performs the non-linear filtering is generated based on correlating an output of a receiver analog-to-digital-converter (ADC) with an output of a corresponding regressor within the non-linear filter;
combining the non-linear replica signal with the received signal.
3. The method of claim 2 , wherein determining the estimated echo signal, comprising:
filtering the transmit signal.
4. A method of reducing non-linear transmit signal components of a receive signal of a transceiver, the method comprising:
the transceiver simultaneously transmitting a transmit signal, and receiving the receive signal;
generating a non-linear replica signal of non-linear transmission signal components that are created in the transceiver by a transmit signal digital-to-analog converter (DAC), and imposed onto the receive signal, wherein generating the non-linear replica signal comprises non-linear filtering the transmit signal and the receive signal, wherein the non-linear filtering comprises linear combinations of regressors, wherein each coefficient of a non-linear filter that performs the non-linear filtering is generated based on correlating an output of a receiver analog-to-digital-converter (ADC) with an output of a corresponding regressor within the non-linear filter;
combining the non-linear replica signal with the received signal.
combining the non-linear replica signal with the transmit signal before the transmit signal is summed with the receive signal.
5. A method of reducing non-linear transmit signal components of a receive signal of a transceiver, the method comprising:
the transceiver simultaneously transmitting a transmit signal, and receiving the receive signal;
generating a non-linear replica signal of non-linear transmission signal components that are created in the transceiver by a transmit signal digital-to-analog converter (DAC), and imposed onto the receive signal, wherein generating the non-linear replica signal comprises non-linear filtering a combination of the transmit signal, an estimated echo signal, and the receive signal, wherein the non-linear filtering comprises linear combinations of regressors, wherein each coefficient of a non-linear filter that performs the non-linear filtering is generated based on correlating an output of a receiver analog-to-digital-converter (ADC) with an output of a corresponding regressor within the non-linear filter;
combining the non-linear replica signal with the received signal.
6. The method of claim 5 , further comprising digital to analog converting the estimated echo signal with an estimated echo signal DAC, and wherein sampling of at least one of the transmit DAC and the estimated echo signal DAC are over-sampled.
7. An Ethernet transceiver comprising:
a transmitter transmitting a transmit signal;
a receiver far receiving a receive signal;
a non-linear filter receiving the transmit signal and generating a non-linear replica signal of non-linear transmit signal digital-to-analog converter (DAC) components imposed onto receive signal in the transceiver, wherein generating the non-linear replica signal comprises non-linear filtering of the transmit signal, wherein the non-linear filtering comprises linear combinations of regressors, wherein each coefficient of a non-linear filter that performs the non-linear filtering is generated based on correlating an output of a receiver analog-to-digital-converter (ADC) with an output of a corresponding regressor within the non-linear filter;
a summer combining the non-linear replica signal with the receive signal.
8. The transceiver of claim 7 , wherein the non-linear filter additionally receives a replica echo signal, and the non-linear replica signal includes non-linear transmission signal DAC components imposed onto the receive signal and non-linear replica echo signal DAC components coupled onto the receive signal.
9. The transceiver of claim 8 , wherein at least one of the transmit DAC and an echo DAC are over-sampled.
10. The transceiver of claim 8 , wherein the replica echo signal is generated by filtering the transmit signal.
11. The transceiver of claim 7 , wherein the non-linear filter additionally receives the receive signal.
12. The transceiver of claim 8 , wherein the non-linear filter additionally receives the receive signal.
13. The transceiver of claim 7 , wherein the non-linear filter comprises linear combinations of known non-linear functions.
14. A method of linearizing a Ethernet received signal of an Ethernet transceiver, comprising:
the transceiver simultaneously transmitting a transmit signal, and receiving the receive signal;
generating a non-linear replica signal, the non-linear replica signal approximating non-linear signal components of the transmit signal imposed onto the receive signal within the transceiver, wherein generating the non-linear replica signal comprises non-linear filtering of the transmit signal, wherein the non-linear filtering filter that performs the non-linear filtering is generated based on correlating an output of a receiver analog-to-digital-converter (ADC) with an output of a corresponding regressor within the non-linear filter;
combining the non-linear replica signal within the transmit signal before the transmit signal is summed with the receive signal.
15. The method of claim 14 , wherein the non-linear filtering comprises linear combinations of known non-linear functions.
16. The method of claim 14 , wherein generating the non-linear replica signal further comprises:
non-linear filtering the transmit signal and non-linear filtering an estimated echo signal.
17. The method of claim 16 , wherein the non-linear components of the transmission signal are generated by a transmit DAC and non-linear elements of the estimated echo signal are generated by an echo DAC, and sampling of at least one of the transmit DAC and the estimated echo signal DAC is over-sampled.