Network using asymmetric uplink and downlink baud rates to reduce crosstalk

Patent metadata

Field	Value
Publication number	US-11943005-B2
Application number	US-202117549744-A
Country	US
Kind code	B2
Filing date	Dec 13, 2021
Priority date	Dec 11, 2020
Publication date	Mar 26, 2024
Grant date	Mar 26, 2024

Abstract

A transmitter transmits a first signal via a first cable at a first baud rate. A receiver receives a second signal via the first cable concurrently with transmitting the first signal via the first cable. The second signal is transmitted by another device at a second baud. rate that is lower than both i) the first baud rate and ii) a third baud rate at which a third signal is being transmitted in a second cable that causes crosstalk in the second signal being received via the first cable. Reception of the second signal at the second baud rate that is lower than the third baud rate facilitates mitigation of the crosstalk in the second signal caused by transmission of the third signal in the second cable at the third baud rate.

First claim

What is claimed is:

1. A first network device for communicating via a first cable and a second cable that is separate from the first cable, comprising:
a first transmitter configured to transmit a first Ethernet signal via the first cable at a first baud rate that corresponds to a first minimum required bandwidth, the first minimum required bandwidth exceeding a maximum bandwidth rating of the first cable;
a second transmitter configured to transmit a second Ethernet signal via the second cable at a second baud rate concurrently with transmission of the first Ethernet signal via the first cable;
a first receiver configured to receive a third Ethernet signal via the first cable concurrently with transmission of the first signal via the first cable and transmission of the second signal via the second cable, the third Ethernet signal having been transmitted by a second network device at a third baud rate that is lower than both i) the first baud rate and ii) the second baud rate, wherein the third baud rate is selected to locate the third Ethernet signal in a frequency range in which a maximum power level of first crosstalk in the first cable is lower than power levels of the first crosstalk at frequencies above the frequency range, the first crosstalk in the first cable caused by the transmission of the second Ethernet signal in the second cable, wherein the third baud rate corresponds to a second minimum required bandwidth that is no more than the maximum bandwidth rating of the first cable, wherein the second baud rate corresponds to a third minimum required bandwidth that exceeds a maximum bandwidth rating of the second cable, and wherein reception of the third Ethernet signal at the third baud rate that is i) lower than the second baud rate, and ii) is no more than the maximum bandwidth rating of the first cable, facilitates mitigation of the first crosstalk in the third Ethernet signal caused by transmission of the second Ethernet signal in the second cable at the second baud rate;
wherein the first receiver includes circuitry configured to process the third Ethernet signal to mitigate second crosstalk in the third Ethernet signal caused by the transmission of the first Ethernet signal in the first cable.

2. The first network device of claim 1 , wherein the third minimum required bandwidth exceeds the maximum bandwidth rating of the first cable.

3. The first network device of claim 1 , further comprising a lowpass filter configured to attenuate the first crosstalk in the first cable caused by transmission of the second Ethernet signal in the second cable at the second baud rate.

4. The first network device of claim 3 , wherein the lowpass filter comprises one or both of:
i) one or more digital lowpass filters; and
ii) an analog lowpass filter.

5. The first network device of claim 1 , further comprising:
a second receiver configured to receive a fourth Ethernet signal via the second cable concurrently with i) transmission of the first Ethernet signal via the first cable, ii) reception of the third Ethernet signal via the first cable, and iii) transmission of the second Ethernet signal via the second cable, the fourth Ethernet signal having been transmitted by a third network device at a fourth baud rate that is lower than both i) the first baud rate and ii) the second baud rate.

6. The first network device of claim 5 , further comprising:
a first lowpass filter configured to attenuate the first crosstalk in the first cable caused by transmission of the second Ethernet signal in the second cable at the second baud rate; and
a second lowpass filter configured to attenuate third crosstalk in the second cable caused by transmission of the first Ethernet signal in the first cable at the first baud rate.

7. The first network device of claim 1 , wherein:
the first transmitter is configured to transmit the first signal at a baud rate of approximately 800 Megasymbols per second (MSps);
the first receiver is configured to receive the third signal at a baud rate of at most 400 MSps; and
the second signal is transmitted at the baud rate of approximately 800 MSps.

8. The first network device of claim 1 , wherein:
the first transmitter is configured to transmit the first Ethernet signal to the second network device via the first cable in a downlink direction;
the first receiver is configured to receive the third Ethernet signal from the second network device via the first cable in an uplink direction; and
the second transmitter is configured to transmit the second Ethernet signal in the downlink direction.

9. The first network device of claim 1 , wherein:
the first transmitter is configured to transmit the first Ethernet signal to the second network device via the first cable in an uplink direction;
the first receiver is configured to receive the third Ethernet signal from the second network device via the first cable in a downlink direction; and
the second transmitter is configured to transmit the second Ethernet signal via the second cable in the uplink direction.

10. A method for communicating via a first cable and a second cable that is separate from the first cable, the method comprising:
transmitting, by a first transceiver of a first network device, a first Ethernet signal via the first cable at a first baud rate that corresponds to a first minimum required bandwidth, the first minimum required bandwidth exceeding a maximum bandwidth rating of the first cable;
transmitting, by a second transceiver of the first network device, a second Ethernet signal via the second cable at a second baud rate concurrently with transmission of the first Ethernet signal via the first cable;
concurrently with transmitting the first Ethernet signal via the first cable and transmitting the second Ethernet signal via the second cable, receiving, by the first transceiver, a third Ethernet signal via the first cable, the third Ethernet signal having been transmitted by a second network device at a third baud rate that is lower than both i) the first baud rate and ii) the second baud rate, wherein the third baud rate is selected to locate the third Ethernet signal in a frequency range in which a maximum power level of first crosstalk in the first cable is lower than power levels of the first crosstalk at frequencies above the frequency range, the first crosstalk in the first cable caused by the transmission of the second Ethernet signal in the second cable, wherein the third baud rate corresponds to a second minimum required bandwidth that is no more than the maximum bandwidth rating of the first cable, wherein the second baud rate corresponds to a third minimum required bandwidth that exceeds a maximum bandwidth rating of the second cable, and wherein reception of the third Ethernet signal at the third baud rate that is i) lower than the second baud rate, and ii) is no more than the maximum bandwidth rating of the first cable, facilitates mitigation of the first crosstalk in the third Ethernet signal caused by transmission of the second Ethernet signal in the second cable at the second baud rate; and
processing, by the first transceiver, the third Ethernet signal to mitigate second crosstalk in the third Ethernet signal caused by the transmission of the first Ethernet signal in the first cable.

11. The method of claim 10 , wherein the third minimum required bandwidth exceeds the maximum bandwidth rating of the first cable.

12. The method of claim 10 , further comprising:
lowpass filtering, at the first transceiver, the third Ethernet signal to attenuate the first crosstalk in the third Ethernet signal caused by transmission of the second Ethernet signal in the second cable at the second

Assignees

• Marvell Asia Pte Ltd

Inventors

• Razavi Majomard Seid Alireza
• Jonsson Ragnar Hlynur
• Shen David

Classifications

• H04B3/32 Primary

  Reducing cross-talk, e.g. by compensating · CPC title

• H04B3/21

  using a set of bandfilters · CPC title