Ethernet physical layer transceiver with non-linear neural network equalizers

Patent metadata

Field	Value
Publication number	US-12166595-B2
Application number	US-202217648834-A
Country	US
Kind code	B2
Filing date	Jan 25, 2022
Priority date	Jan 25, 2021
Publication date	Dec 10, 2024
Grant date	Dec 10, 2024

Abstract

A physical layer transceiver for connecting a host device to a wireline channel medium includes a host interface for coupling to the host device, a line interface for coupling to the channel medium, a transmit path operatively coupled to the host interface and the line interface, a receive path operatively coupled to the line interface and the host interface, and adaptive filter circuitry operatively coupled to at least one of the transmit path and the receive path for filtering signals on the at least one of the transmit path and the receive path, the adaptive filter circuitry including a non-linear equalizer. The non-linear equalizer may be a neural network equalizer based on a multi-layer perceptron or a radial-basis function, or may be a linear equalizer with a non-linear activation function. The non-linear equalizer also may have a front-end filter to reduce input complexity.

First claim

What is claimed is:

1. A physical layer transceiver for connecting a host device to a wireline channel medium, the physical layer transceiver comprising:
a host interface for coupling to the host device;
a line interface for coupling to the wireline channel medium;
a transmit path operatively coupled to the host interface and the line interface, including circuitry for encoding host data and driving multi-level encoded host data onto the wireline channel medium;
a receive path operatively coupled to the line interface and the host interface, including circuitry for decoding multi-level data received from the wireline channel medium and passing the decoded data to the host interface;
adaptive filter circuitry operatively coupled to at least one of the transmit path and the receive path for filtering signals on the at least one of the transmit path and the receive path, the adaptive filter circuitry comprising a non-linear equalizer; and
adaptation circuitry configured to compare output of the adaptive filter circuitry to known data, and to adapt the adaptive filter circuitry, by adjusting parameters of the adaptive filter circuitry, based on cross-entropy between a respective multi-bit symbol and a log-likelihood ratio corresponding to the respective multi-bit symbol.

2. The physical layer transceiver of claim 1 , wherein the adaptive filter circuitry comprises a non-linear equalizer inline in the transmit path and configured to equalize transmit signals.

3. The physical layer transceiver of claim 1 , wherein the adaptive filter circuitry comprises a non-linear equalizer inline in the receive path and configured to equalize received signals.

4. The physical layer transceiver of claim 1 , wherein the adaptive filter circuitry comprises non-linear echo cancellation circuitry coupled to both the transmit path and the receive path and configured to cancel echo between the transmit path and the receive path.

5. The physical layer transceiver of claim 4 , wherein the adaptive filter circuitry comprises non-linear echo cancellation circuitry operating in an analog domain of the physical layer transceiver.

6. The physical layer transceiver of claim 4 , wherein the adaptive filter circuitry comprises non-linear echo cancellation circuitry operating in a digital domain of the physical layer transceiver.

7. The physical layer transceiver of claim 4 , wherein the adaptive filter circuitry comprises non-linear crosstalk cancellation circuitry coupled to both the transmit path and the receive path for cancelling at least one of (a) near-end crosstalk, and (b) far-end crosstalk, between the transmit path and the receive path.

8. The physical layer transceiver of claim 1 , wherein the non-linear equalizer comprises a neural network equalizer.

9. The physical layer transceiver of claim 8 , wherein the neural network equalizer comprises a multi-layer perceptron neural network equalizer.

10. The physical layer transceiver of claim 8 , wherein the neural network equalizer comprises a radial-basis function neural network equalizer.

11. The physical layer transceiver of claim 8 , wherein the neural network equalizer is a reduced complexity neural network equalizer including a front-end filter having a first number of inputs and a second number of outputs, the second number being smaller than the first number, and a neural network filter having as inputs the outputs of the front-end filter.

12. The physical layer transceiver of claim 11 , wherein the front-end filter of the reduced complexity neural network equalizer comprises a finite-impulse-response filter to reduce the first number of inputs to the second number of inputs.

13. The physical layer transceiver of claim 1 , wherein the non-linear equalizer comprises a linear filter and a non-linear activation function.

14. The physical layer transceiver of claim 13 , wherein the non-linear activation function is a hyperbolic tangent function.

15. The physical layer transceiver of claim 13 , wherein the non-linear activation function is a sigmoid function.

16. A method of filtering interference in a physical layer transceiver for connecting a host device to a wireline channel medium, the method comprising:
performing non-linear equalization on at least one of a transmit path and a receive path for filtering multi-level signals on the at least one of the transmit path and the receive path; and
adapting a non-linear equalizer, by adjusting parameters of the non-linear equalizer, based on cross-entropy between multi-bit symbols in equalizer output and multi-bit symbols in data signals on the wireline channel medium.

17. The method of filtering interference in a physical layer transceiver according to claim 16 , wherein performing non-linear equalization on at least one of the transmit path and the receive path comprises performing non-linear equalization inline in the transmit path to equalize transmit signals.

18. The method of filtering interference in a physical layer transceiver according to claim 16 , wherein performing non-linear equalization on at least one of the transmit path and the receive path comprises performing non-linear equalization inline in the receive path to equalize received signals.

19. The method of filtering interference in a physical layer transceiver according to claim 16 , wherein performing non-linear equalization comprises performing non-linear echo cancellation between the transmit path and the receive path.

20. The method of filtering interference in a physical layer transceiver according to claim 16 , wherein performing non-linear equalization comprises performing non-linear crosstalk cancellation for cancelling at least one of (a) near-end crosstalk, and (b) far-end crosstalk, between the transmit path and the receive path.

21. The method of filtering interference in a physical layer transceiver according to claim 16 , wherein performing non-linear equalization comprises applying a non-linear activation function and performing linear filtering.

22. The method of filtering interference in a physical layer transceiver according to claim 21 , wherein applying a non-linear activation function comprises applying a hyperbolic tangent function.

23. The method of filtering interference in a physical layer transceiver according to claim 21 , wherein applying a non-linear activation function comprises applying a sigmoid function.

24. The method of filtering interference in a physical layer transceiver according to claim 16 , further comprising applying initial filtering of equalization inputs prior to performing the non-linear equalization, to reduce complexity by reducing number of inputs to the non-linear equalization.

25. The method of filtering interference in a physical layer transceiver according to claim 24 , wherein applying initial filtering comprises applying finite-impulse-response filtering.

Assignees

• Marvell Asia Pte Ltd

Inventors

• Nangare Nitin

Classifications

• H04L25/03878

  Line equalisers; line build-out devices · CPC title

• H04L25/0254

  using neural network algorithms · CPC title

• H04L25/0252

  using third or higher order statistics · CPC title

• H04L25/0234

  by non-linear interpolation · CPC title

• G06N3/048

  Activation functions · CPC title