SIGNAL TRANSMISSION SYSTEM, INTERFACE DEVICE, AND SIGNAL TRANSMISSION METHOD

• US 20100128766A1
• Filed: 10/22/2009
• Published: 05/27/2010
• Est. Priority Date: 11/26/2008
• Status: Active Grant

• Current Assignee: Sony Corporation (Sony Group Corp.)
• Original Assignee: Sony Corporation (Sony Group Corp.)
• Inventors: SUGITA, Takehiro
• Granted Patent: US 8,533,375 B2
• Time in Patent Office: Days
• US Class Current: 375/220
• CPC Class Codes: H04L 25/4904 using self-synchronising codes, e.g. split-phase codes
• CPC Class Codes: H04L 7/0008 Synchronisation information channels, e.g. clock distribution lines

Abstract

There is provided a signal transmission system including an information processing device and an interface device. The information processing device codes transmitted data into a code that does not include a direct-current component, and the information processing device transmits the code while superimposing the code on a direct-current power. A polarity of the code is inverted every half a period of a clock. The interface device detects a polarity inversion period of a signal received from the information processing device, and the interface device reproduces the clock based on the detection result.

Claims

1. A signal transmission system comprising an information processing device and an interface device, wherein the information processing device includes:

a data coding unit that codes data into first transmitted data, the first transmitted data not including a direct-current component;

a signal sending unit that superimposes a signal of the first transmitted data produced by the data coding unit on a direct current and sends the superimposed signal to the interface device through a predetermined signal line; and

a signal separation unit that receives a signal of second transmitted data on which the direct current is superimposed through the predetermined signal line and separates the received signal into the signal of the second transmitted data and the direct current, and

the interface device includes;

a data input and output terminal that is used to supply and feed the data;

a signal separation unit that receives the signal of the first transmitted data on which the direct current is superimposed through the predetermined signal line and separates the received signal into the signal of the first transmitted data and the direct current;

a signal receiving unit that receives the signal of the first transmitted data;

a clock reproducing unit that reproduces a clock from the signal of the first transmitted data received by the signal receiving unit;

a data decoding unit that decodes the first transmitted data using the clock reproduced by the clock reproducing unit and supplies the decoded first transmitted data to the data input and output terminal;

a data coding unit that codes the second transmitted data into a code shape that does not include a direct-current component using the clock reproduced by the clock reproducing unit, the second transmitted data being fed from the data input and output terminal; and

a signal sending unit that superimposes the signal of the second transmitted data produced by the data coding unit on the direct current and sends the superimposed data through the predetermined signal line.

2. The signal transmission system according to claim 1, wherein the data coding unit of the information processing device codes the transmitted data into a code shape whose polarity is inverted every half a period of the clock.

3. The signal transmission system according to claim 2, wherein the clock reproducing unit detects a polarity inversion period of the data signal, and the clock reproducing unit reproduces the clock based on the detection result.

4. The signal transmission system according to claim 1, wherein the information processing device further includes:

an internal secondary battery that supplies the direct current; and

a voltage sensing unit that senses a voltage of the direct current separated by the signal separation unit,

wherein the signal sending unit stops a charge circuit that charges the internal secondary battery when the voltage sensed by the voltage sensing unit is equal to or lower than a predetermined value.

5. The signal transmission system according to claim 4, wherein the information processing device is operated using the direct current when the direct current is supplied from the interface,

the information processing device is operated using the direct current supplied from the internal secondary battery when the direct current is not supplied from the interface, and

the information processing device superimposes the transmitted data on the direct current supplied from the secondary battery.

6. The signal transmission system according to claim 1, wherein the interface device is operated using the direct current when the information processing device supplies the direct current.

7. An interface device comprising:

a data input and output terminal that is used to supply and feed the data;

a signal separation unit that receives a signal of first transmitted data on which a direct current is superimposed through a predetermined signal line and separates the received signal into the signal of the first transmitted data and the direct current;

a signal receiving unit that receives the signal of the first transmitted data through the predetermined signal line, the signal of the first transmitted data being coded in a code that does not include a direct-current component;

a clock reproducing unit that reproduces a clock from the signal of the first transmitted data received by the signal receiving unit;

a data decoding unit that decodes the first transmitted data using the clock reproduced by the clock reproducing unit and supplies the decoded first transmitted data to the data input and output terminal;

a data coding unit that codes second transmitted data into a code shape that does not include the direct-current component using the clock reproduced by the clock reproducing unit, the second transmitted data being fed from the data input and output terminal; and

a signal sending unit that superimposes the direct current on the signal of the second transmitted data produced by the data coding unit and sends the superimposed data through the predetermined signal line.

8. The interface device according to claim 7, wherein the signal receiving unit receives the signal of the first transmitted data through the predetermined signal line, the first transmitted data being coded into a code shape whose polarity is inverted every half a period of the clock.

9. The interface device according to claim 8, wherein the clock reproducing unit detects a polarity inversion period of the data signal, and the clock reproducing unit reproduces the clock based on the detection result.

12. The interface device according to claim 7, further comprising:

a current supply terminal to which an alternating current is supplied from an external power supply; and

a conversion circuit that converts the alternating current supplied to the current supply terminal into the direct current,

wherein the signal sending unit sends the signal of the second transmitted data while superimposing the signal of the second transmitted data on the direct current supplied from the conversion circuit.

13. The interface device according to claim 7, further comprising a current supply terminal to which the direct current is supplied,

wherein the signal sending unit sends the signal of the second transmitted data while superimposing the signal of the second transmitted data on the direct current supplied from the current supply terminal.

14. The interface device according to claim 7, wherein the data coding unit codes the second transmitted data into a code shape that is selected a group consisting of at least an AMI (Alternate Mark Inversion) code, a CMI (Coded Mark Inversion) code, a partial response code, a Manchester code, and a bi-phase code including AM (Amplitude Modulation) modulation.

10. An information processing device comprising:

a data coding unit that codes data into first transmitted data, the first transmitted data not including a direct-current component;

a signal sending unit that superimposes a signal of the first transmitted data produced by the data coding unit on a direct current and sends the superimposed signal to the interface device through a predetermined signal line; and

a signal separation unit that receives a signal of second transmitted data on which the direct current is superimposed through the predetermined signal line and separates the received signal into the signal of the second transmitted data and the direct current.

11. The information processing device according to claim 10, wherein the data coding unit codes the transmitted data into a code shape whose polarity is inverted every half a period of the clock.

15. An interface device comprising:

a data input and output terminal that is used to supply and feed the data;

a signal receiving unit that receives a superimposed signal through a predetermined signal line, a signal of first transmitted data and a direct current are superimposed in the superimposed signal, the signal of the first transmitted data being coded into a code that does not include a direct-current component;

a signal separation unit that separates the superimposed signal received by the signal receiving unit into the signal of the first transmitted data and the direct current;

a clock reproducing unit that reproduces a clock from the signal of the first transmitted data separated by the signal separation unit;

a data decoding unit that decodes the first transmitted data using the clock reproduced by the clock reproducing unit and supplies the decoded first transmitted data to the data input and output terminal;

a data coding unit that codes second transmitted data into a code shape that does not include the direct-current component using the clock reproduced by the clock reproducing unit, the second transmitted data being fed from the data input and output terminal; and

a signal sending unit that superimposes the signal of the second transmitted data produced by the data coding unit on the direct current and sends the superimposed data through the predetermined signal line.

16. The interface device according to claim 15, wherein the signal receiving unit receives the signal of the first transmitted data through the predetermined signal line, the first transmitted data being coded into a code shape whose polarity is inverted every half a period of the clock.

17. The interface device according to claim 16, wherein the clock reproducing unit detects a polarity inversion period of the data signal, and the clock reproducing unit reproduces the clock based on the detection result.

18. A signal transmission method, comprising the steps of:

coding data into first transmitted data with an information processing device, the code not including a direct-current component;

superimposing a signal of the first transmitted data produced by the data coding unit on a direct current with the information processing device and sending the superimposed signal to an interface device through a predetermined signal line with the information processing device;

receiving a signal of second transmitted data on which the direct current is superimposed through the predetermined signal line with the information processing device and separating the received signal into the signal of the second transmitted data and the direct current with the information processing device;

supplying and feeding the data through a data input and output terminal that is used to supply and feed the data with the interface device;

receiving the signal of the first transmitted data on which the direct current is superimposed through the predetermined signal line with the interface device and separating the received signal into the signal of the first transmitted data and the direct current with the interface device;

receiving the signal of the first transmitted data through the predetermined signal line with the interface device;

reproducing a clock from the signal of the first transmitted data received in the signal receiving step with the interface device;

decoding the first transmitted data with the interface device using the clock reproduced in the clock reproducing step and supplying the decoded first transmitted data to the data input and output terminal with the interface device;

coding the second transmitted data into a code shape that does not include a direct-current component with the interface device using the clock reproduced in the clock reproducing step, the second transmitted data being fed from the data input and output terminal; and

superimposing the signal of the second transmitted data produced in the data coding step on the direct current with the interface device and sending the superimposed data through the predetermined signal line with the interface device.

19. A signal transmission method, comprising the steps of:

supplying and feeding data through a data input and output terminal that is used to supply and feed the data;

receiving a signal of first transmitted data on which a direct current is superimposed through a predetermined signal line and separating the received signal into the signal of the first transmitted data and the direct current;

receiving the signal of the first transmitted data through the predetermined signal line, the signal of the first transmitted data being coded in a code that does not include a direct-current component;

reproducing a clock from the signal of the first transmitted data received in the signal receiving step;

decoding the first transmitted data using the clock reproduced in the clock reproducing step and supplying the decoded first transmitted data to the data input and output terminal;

coding second transmitted data into a code shape that does not include the direct-current component using the clock reproduced in the clock reproducing step, the second transmitted data being fed from the data input and output terminal; and

superimposing the direct current on the signal of the second transmitted data produced in the data coding step and sending the superimposed data through the predetermined signal line.

20. A signal transmission method, comprising the steps of:

supplying and feeding data through a data input and output terminal that is used to supply and feed the data;

receiving a superimposed signal through a predetermined signal line, a signal of first transmitted data and a direct current are superimposed in the superimposed signal, the signal of the first transmitted data being coded into a code that does not include a direct-current component;

separating the superimposed signal received in the signal receiving step into the signal of the first transmitted data and the direct current;

reproducing a clock from the signal of the first transmitted data separated in the signal separation step;

decoding the first transmitted data using the clock reproduced in the clock reproducing step and supplying the decoded first transmitted data to the data input and output terminal;

coding second transmitted data into a code shape that does not include the direct-current component using the clock reproduced in the clock reproducing step, the second transmitted data being fed from the data input and output terminal; and

superimposing the signal of the second transmitted data produced in the data coding step on the direct current and sending the superimposed data through the predetermined signal line.