Distributed dynamic power savings for adaptive filters in a high-speed data channel

Patent metadata

Field	Value
Publication number	US-11310084-B2
Application number	US-202117248082-A
Country	US
Kind code	B2
Filing date	Jan 8, 2021
Priority date	Jan 10, 2020
Publication date	Apr 19, 2022
Grant date	Apr 19, 2022

Abstract

A physical layer transceiver for a wireline channel medium includes a host interface to a host device, a line interface to the medium, encoding/decoding circuitry for interfacing between the host device and the medium, and adaptive filter circuitry coupled to the encoding/decoding circuitry. The adaptive filter circuitry includes a plurality of filter taps, each corresponding to a segment of the medium, and capable of being powered ON and OFF separately from each other filter tap. Adaptive control circuitry can power ON a first subset, fewer than all the filter taps, corresponding to segments distributed along the medium, monitor powered-ON filter taps for occurrence of interference events, and upon detection of an interference event at a particular segment to which a particular powered-ON filter tap corresponds, power ON one or more additional filter taps corresponding to one or more segments in a vicinity of the particular segment.

First claim

What is claimed is:

1. A physical layer transceiver for connecting a host device to a wireline channel medium having a cable length, the physical layer transceiver comprising:
a host interface for coupling to the host device;
a line interface for coupling to the wireline channel medium;
encoding/decoding circuitry operatively coupled to the host interface and the line interface for interfacing between the host device and the wireline channel medium; and
adaptive filter circuitry operatively coupled to the encoding/decoding circuitry, the adaptive filter circuitry comprising:
a plurality of filter taps, each filter tap in the plurality of filter taps corresponding to a segment of the cable length of the wireline channel medium, and being capable of being powered ON and OFF separately from each other filter tap in the plurality of filter taps, and
adaptive control circuitry configured to:
power ON a first subset of the plurality of filter taps, fewer than all of the filter taps, corresponding to segments distributed along the cable length of the wireline channel medium,
monitor powered-ON filter taps for occurrence of interference events, and
upon detection of an interference event at a segment to which a particular powered-ON filter tap corresponds, power ON one or more additional filter taps corresponding to one or more segments in a vicinity of segment to which the particular filter tap corresponds.

2. The physical layer transceiver of claim 1 wherein the adaptive control circuitry is configured to initially power ON, as the first subset of the plurality of filter taps, filter taps corresponding to segments that are distributed along the cable length of the wireline channel medium.

3. The physical layer transceiver of claim 2 wherein the adaptive control circuitry is configured to initially power ON, as the first subset of the plurality of filter taps, every other filter tap, corresponding to every other segment along the cable length of the wireline channel medium, wherein both taps neighboring each ON tap that is not an end tap are OFF, and both taps neighboring each OFF tap that is not an end tap are ON.

4. The physical layer transceiver of claim 2 wherein the adaptive control circuitry is configured to initially power ON, as the first subset of the plurality of filter taps, every third filter tap, corresponding to every third segment along the cable length of the wireline channel medium, wherein both taps neighboring each ON tap that is not an end tap are OFF, and each OFF tap that is not an end tap has a first neighboring tap that is ON and a second neighboring tap that is OFF.

5. The physical layer transceiver of claim 1 wherein the adaptive control circuitry is configured to initially power ON, as the first subset of the plurality of filter taps, different distributions of filter taps corresponding to different blocks along the cable length of the wireline channel medium.

6. The physical layer transceiver of claim 5 wherein the different distributions of powered-ON filter taps corresponding to the different blocks comprise:
a first proportion of powered-ON filter taps corresponding to a block having a first susceptibility to interference; and
a second proportion, greater than the first proportion, of powered-ON filter taps corresponding to a block having a second susceptibility, greater than the first susceptibility, to interference.

7. The physical layer transceiver of claim 6 wherein the different distributions of powered-ON filter taps corresponding to the different blocks comprise:
the first proportion of powered-ON filter taps, wherein the first proportion of powered-ON filter taps corresponds to a block of segments in a portion of the wireline channel medium remote from a connector; and
the second proportion of powered-ON filter taps, wherein the second proportion of powered-ON filter taps corresponds to a block of segments in a portion of the wireline channel medium adjacent to a connector.

8. The physical layer transceiver of claim 6 wherein the different distributions of powered-ON filter taps corresponding to the different blocks comprise:
the first proportion of powered-ON filter taps, wherein the first proportion of powered-ON filter taps corresponds to a block of segments in a portion of the wireline channel medium that is not subject to changes in temperature; and
the second proportion of powered-ON filter taps, wherein the second proportion of powered-ON filter taps corresponds to a block of segments in a portion of the wireline channel medium that is subject to changes in temperature.

9. The physical layer transceiver of claim 6 wherein the different distributions of powered-ON filter taps corresponding to the different blocks comprise:
the first proportion of powered-ON filter taps, wherein the first proportion of powered-ON filter taps corresponds to a block of segments in a portion of the wireline channel medium that is not subject to physical disturbance; and
the second proportion of powered-ON filter taps, wherein the second proportion of powered-ON filter taps corresponds to a block of segments in a portion of the wireline channel medium that is subject to physical bending.

10. The physical layer transceiver of claim 9 wherein:
the physical layer transceiver is for use in an automotive Ethernet system in which the wireline channel medium is an automotive Ethernet cable in a vehicle; and
the different distributions of powered-ON filter taps corresponding to the different blocks comprise:
the first proportion of powered-ON filter taps, wherein the first proportion of powered-ON filter taps corresponds to a block of segments in a portion of the automotive Ethernet cable that is well-secured to the vehicle, and
the second proportion of powered-ON filter taps, wherein the second proportion of powered-ON filter taps corresponds to a block of segments in a portion of the automotive Ethernet cable that is poorly secured to the vehicle.

11. The physical layer transceiver of claim 1 wherein the adaptive control circuitry is further configured to:
upon lack of detection, after a predetermined time period has elapsed, of an interference event in segments to which a group of filter taps that are powered-ON correspond, power OFF one or more filter taps in the group of filter taps.

12. The physical layer transceiver of claim 11 wherein the adaptive control circuitry is configured to:
power OFF the one or more filter taps in the group of filter taps that are powered-ON, when total interference energy of filter taps in the group of filter taps that are powered-ON falls below a first predetermined threshold; and
power ON the one or more additional filter taps in the vicinity of the particular filter tap when total interference energy of filter taps in the group of filter taps, corresponding to segments in the vicinity of the segment to which the particular filter tap corresponds, that are powered-ON, exceeds a second predetermined threshold greater than the first predetermined threshold.

13. A method of filtering interference in a physical layer transceiver for connecting a host device to a wireline channel medium having a cable length, and having adaptive filter circuitry including a plurality of filter taps, each filter tap in the plurality of filter taps corresponding to a segment of the cable length of the wireline channel medium, and being separately controllable from each other filter tap in the plurality of filter taps, the method comprising:
powering ON a first subset of the plurality of filter taps, fewer than all of the filter taps, corresponding to segments distributed along the cable length of the

Assignees

• Marvell Asia Pte Ltd

Inventors

• Shen David
• Weiss Oliver

Classifications

• H04L25/0212

  of impulse response · CPC title

• H04B3/23

  using a replica of transmitted signal in the time domain, e.g. echo cancellers · CPC title

• H04L25/03044

  using fractionally spaced delay lines or combinations of fractionally integrally spaced taps · CPC title

• H04L25/03057

  with a recursive structure (H04L25/03031 takes precedence) · CPC title

• H04B3/237

  using two adaptive filters, e.g. for near end and for end echo cancelling · CPC title