Method and apparatus for reducing ethernet power consumption for vehicles

Patent metadata

Field	Value
Publication number	US-10698473-B2
Application number	US-201816189548-A
Country	US
Kind code	B2
Filing date	Nov 13, 2018
Priority date	Oct 11, 2018
Publication date	Jun 30, 2020
Grant date	Jun 30, 2020

Abstract

A method for reducing power consumption in an electronic control unit (ECU) equipped with an Ethernet communication function and mounted in a vehicle include initializing a physical layer upon restarting of the physical layer and setting a transmission mode to a data mode. The method includes generating a clock signal having a first frequency for Ethernet communication, checking presence or absence of a normal frame to be transmitted, checking presence or absence of an idle frame based on a reception signal symbol, and determining whether to change the frequency of the clock signal based on checking results in the checking of presence or absence of a normal frame and the checking of presence or absence of an idle frame.

First claim

What is claimed is:

1. A method for reducing power consumption in an electronic control unit (ECU) equipped with an Ethernet communication function and mounted in a vehicle, the method comprising:
initializing a physical layer upon restarting of the physical layer and setting a transmission mode to a data mode;
generating a clock signal having a first frequency for Ethernet communication;
checking presence or absence of a normal frame to be transmitted;
checking presence or absence of an idle frame based on a reception signal symbol; and
determining whether to change the frequency of the clock signal based on checking results in the checking of presence or absence of a normal frame and in the checking of presence or absence of an idle frame.

2. The method according to claim 1 , wherein, upon checking that a normal frame to be transmitted is not present in the checking of presence or absence of a normal frame and an idle frame is present in the checking of presence or absence of an idle frame, the first frequency of the clock signal is changed to a second frequency.

3. The method according to claim 2 , wherein, when a normal frame to be transmitted is present or a frame checked based on the reception signal symbol is a normal frame in a state in which the first frequency has been changed to the second frequency, the frequency of the clock signal is changed to the first frequency.

4. The method according to claim 3 , wherein, when the reception signal symbol is a zero symbol (0, 0) in a state in which a normal frame to be transmitted is not present, a frame receiver thereafter is determined to be a normal frame and the frequency of the clock signal is changed to the first frequency.

5. The method according to claim 2 , wherein the second frequency is lower than the first frequency.

6. The method according to claim 1 , further comprising identifying whether the ECU is a master device,
wherein the frequency of the clock signal is changeable only when the ECU is a master device.

7. The method according to claim 1 , wherein the checking of presence or absence of an idle frame comprises checking whether a reception signal symbol pattern is a predefined electrostatic discharge (ESD) symbol pattern, and
wherein a frame received thereafter is determined to be the idle frame when the reception signal symbol pattern is the ESD symbol pattern.

8. The method according to claim 1 , wherein the ESD symbol pattern is composed of three consecutive reception signal symbols (0, 0), (0, 0) and (0, 1).

9. The method according to claim 1 , wherein the idle frame has a variable length.

10. An apparatus for reducing Ethernet power consumption for vehicles, mounted in a vehicle to perform Ethernet communication, the apparatus comprising:
a media access control (MAC) layer including a main controller and a clock generator; and
a physical layer for processing data transmitted/received to/from the MAC layer to perform Ethernet communication,
wherein the physical layer comprises:
a physical coding sublayer (PCS) transmitter for generating transmission signal symbols based on transmission data received by the main controller;
a physical medium attachment (PMA) transmitter for generating an Ethernet signal based on the transmission signal symbols received from the PCS transmitter and transmitting the Ethernet signal through a communication line;
a PMA receiver for generating reception signal symbols based on an Ethernet signal detected in the communication line;
a PCS receiver for receiving the reception signal symbols from the PMA receiver, generating reception data and transmitting the reception data to the main controller; and
a clock controller for receiving a clock signal having a first frequency from the clock generator and changing the frequency of the clock signal based on a communication state on the communication line.

11. The apparatus according to claim 10 , wherein the clock controller comprises:
an idle detector for determining a time at which the frequency of the clock signal is changed based on a transmission enable signal (signal TX_EN) received from the main controller and the reception signal symbols; and
a clock converter for changing the frequency of the clock signal according to a control signal of the idle detector and outputting the clock signal.

12. The apparatus according to claim 11 , wherein the clock signal output from the clock converter is provided to the PCS transmitter and the PMA transmitter.

13. The apparatus according to claim 11 , wherein, when the idle detector confirms that a normal frame to be transmitted is not present according to the signal TX_EN and confirms that a frame to be received is an idle frame according to the reception signal symbols, the frequency of the clock signal is changed to a second frequency.

14. The apparatus according to claim 13 , wherein, the clock converter changes the frequency of the clock signal to the first frequency when a normal frame to be transmitted is present or a frame checked based on the reception signal symbols is a normal frame in a state in which the frequency of the clock signal has been changed to the second frequency.

15. The apparatus according to claim 13 , wherein, when the reception signal symbols are zero symbols (0, 0) in a state in which a normal frame to be transmitted is not present, a frame to be received thereafter is determined to be a normal frame and the frequency of the clock signal is changed to the first frequency.

16. The apparatus according to claim 13 , wherein the second frequency is lower than the first frequency.

17. The apparatus according to claim 10 , wherein the frequency of the clock signal is changeable only when the apparatus for reducing Ethernet power consumption for vehicles is a master device.

18. The apparatus according to claim 13 , wherein the idle detector checks whether a reception signal symbol pattern is a predefined ESD symbol pattern and determines that a frame received thereafter is an idle frame when the reception signal symbol pattern is the ESD symbol pattern.

19. The apparatus according to claim 18 , wherein the ESD symbol pattern is composed of three consecutive reception signal symbols (0, 0), (0, 0) and (0, 1).

20. The apparatus according to claim 10 , wherein the main controller transmits a clock converter enable signal (signal CC_EN) for enabling or disabling the operation of the clock converter to the clock controller, and the clock controller bypasses a clock signal from the clock generator such that the control signal is provided to the PCS transmitter and the PMA transmitter when the clock converter is disabled by the signal CC_EN.

Assignees

• Hyundai Motor Co Ltd
• Kia Motors Corp
• Kia Motors Company

Inventors

• Park Soon Chul

Classifications

• H04L12/4013 Primary

  Management of data rate on the bus (systems modifying transmission characteristics according to link quality H04L1/0001) · CPC title

• H04L12/40039 Primary

  Details regarding the setting of the power status of a node according to activity on the bus · CPC title

• H04L2012/40273

  the transportation system being a vehicle · CPC title

• Y02D10/00

  Energy efficient computing, e.g. low power processors, power management or thermal management · CPC title

• Y02D30/50

  in wire-line communication networks, e.g. low power modes or reduced link rate · CPC title