POWER LINE COMMUNICATION SYSTEM FOR VEHICLE

• US 20140064388A1
• Filed: 08/29/2013
• Published: 03/06/2014
• Est. Priority Date: 09/03/2012
• Status: Active Grant

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: MURASE, Yuukou, SUGIURA, Yoshie, TAKAOKA, Akira, WANG, Fan
• Granted Patent: US 8,948,275 B2
• Time in Patent Office: Days
• US Class Current: 375/257
• CPC Class Codes: H04B 3/548 the power on the line being DC arrangements for feeding power H04L12/10; extracting feeding power from signals H04L25/02

Abstract

In a power line communication system, a master uses a twisted pair wire as a power line and a communication line and outputs a power signal and a data modulation signal to a slave. The slave includes an aperture antenna, a power monitoring portion, and a determining portion. The aperture antenna receives the power signal via the twisted pair wire by electromagnetic induction coupling of an electromagnetic field generated at the twisted pair wire in accordance with an applied current of the twisted pair wire. The aperture antenna has an aperture region facing an aperture region between twists of the twisted pair wire. The power monitoring portion monitors a power of the power signal received via the first aperture antenna. The determination portion determines whether to use another operation power received via the twisted pair wire on the basis of the power monitored by the power monitoring portion.

Claims

1. A power line communication system for a vehicle comprising:

a master using a twisted pair wire, in which core wires are connected at an end to form a loop shape, as a power line and a communication line and outputting a high-frequency signal to the twisted pair wire to transmit a power signal and a data modulation signal; and

a slave receiving the power signal and the data modulation signal transmitted from the master, the slave including an aperture antenna, a power monitoring portion, and a determining portion, the aperture antenna having a loop shape and receiving the power signal via the twisted pair wire by electromagnetic induction coupling of an electromagnetic field generated at the twisted pair wire in accordance with an applied current of the twisted pair wire, the aperture antenna having an aperture region facing an aperture region between twists of the twisted pair wire, the slave operating by the power signal received via the aperture antenna, the power monitoring portion monitoring a power of the power signal received via the aperture antenna, the determination portion determining whether to use another operation power received via the twisted pair wire on the basis of the power monitored by the power monitoring portion.

2. The power line communication system according to claim 1, wherein

the determining portion determines to use the another operation power on condition that the power monitored by the monitoring portion is less than a predetermined threshold power.

3. The power line communication system according to claim 1, wherein

the aperture antenna is a first aperture antenna,

the slave further includes a second aperture antenna and a setting portion,

the second aperture antenna has a loop shape and receives the data modulation signal via the twisted pair wire by electromagnetic induction coupling of the electromagnetic field generated at the twisted pair wire in accordance with the applied current of the twisted pair wire, and

the setting portion sets to use the data modulation signal received from the second aperture antenna as the another operation power instead of the power signal received via the first aperture antenna when the determining portion determines to use the another operation power.

4. The power line communication system according to claim 1, wherein

the aperture antenna is a first aperture antenna,

the slave further includes a second aperture antenna and a setting portion,

the second aperture antenna has a loop shape and receives the data modulation signal via the twisted pair wire by electromagnetic induction coupling of the electromagnetic field generated at the twisted pair wire in accordance with the applied current of the twisted pair wire, and

the setting portion sets to use the data modulation signal received from the second aperture antenna as the another operation power in addition to the power signal received via the first aperture antenna when the determining portion determines to use the another operation power.

5. The power line communication system according to claim 1, wherein

the determining portion determines to use the another operation power on condition that the power monitored by the monitoring portion fluctuates and repeatedly falls below a predetermined threshold power a predetermined number of times or more.

6. The power line communication system according to claim 1, wherein

the slave further includes an electric storage device and a setting portion,

the electric storage device stores the power signal received from the aperture antenna, and

the setting portion sets to use the power signal stored at the electric storage device as the another operation power when the determining portion determines to use the another operation power.

7. The power line communication system according to claim 1, wherein

the aperture antenna is a first aperture antenna,

the slave further includes a second aperture antenna, an electric storage device, and a setting portion,

the second aperture antenna has a loop shape and receives the data modulation signal via the twisted pair wire by electromagnetic induction coupling of the electromagnetic field generated at the twisted pair wire in accordance with the applied current of the twisted pair wire,

the electric storage device stores the data modulation signal received from the second aperture antenna as a power signal, and

the setting portions sets to use the power signal stored at the electric storage device as the another operation power when the determining portion determines to use the another operation power.

8. The power line communication system according to claim 1, wherein

the aperture antenna is a first aperture antenna,

the slave further includes a second aperture antenna, an electric storage device, and a setting portion,

the second aperture antenna has a loop shape and receives the data modulation signal via the twisted pair wire by electromagnetic induction coupling of

the electromagnetic field generated at the twisted pair wire in accordance with the applied current of the twisted pair wire,

the electric storage device stores the power signal received from the first aperture antenna and the data modulation signal received from the second aperture antenna as power signals, and

the setting portions sets to use the power signals stored at the electric storage device as the another operation power when the determining portion determines to use the another operation power.

9. The power line communication system according to claim 1, wherein

the slave further includes a responding portion,

the responding portion informs the master that the power supplied to the slave is low when the determining portion determines to use the another operation power,

the master further includes a frequency control portion, and

the frequency control portion changes a carrier frequency of the power signal of the high-frequency signal when the master is informed by the responding portion that the power supplied to the slave is low.

10. The power line communication system according to claim 1, wherein

the slave further includes a responding portion,

the responding portion informs the master that the power supplied to the slave is low when the determining portion determines to use the another operation power,

the master further includes an output control portion, and

the output control portion increases an output power of the power signal of the high-frequency signal when the master is informed by the responding portion that the power supplied to the slave is low.

11. The power line communication system according to claim 1, wherein

the slave further includes a responding portion,

the responding portion informs the master that the power supplied to the slave is low when the determining portion determines to use the another operation power,

the master further includes a matching control portion,

the matching control portion performs a matching control with respect to the twisted pair wire when the master is informed by the responding portion that the power supplied to the slave is low.

12. A receiving device for communicating with a master via a twisted pair wire as a power line and a communication line, the receiving device comprising

a slave receiving a power signal and a data modulation signal from the master, the slave including an aperture antenna, a power monitoring portion, and a determining portion, the aperture antenna having a loop shape and receiving the power signal via the twisted pair wire by electromagnetic induction coupling of an electromagnetic field generated at the twisted pair wire in accordance with an applied current of the twisted pair wire, the aperture antenna having an aperture region facing an aperture region between twists of the twisted pair wire, the slave operating by the power signal received via the aperture antenna, the power monitoring portion monitoring a power of the power signal received via the aperture antenna, the determination portion determining whether to use another operation power received via the twisted pair wire on the basis of the power monitored by the power monitoring portion.