Power transfer apparatus for concurrently transmitting data and power over data wires

• US 6,329,906 B1
• Filed: 09/29/2000
• Issued: 12/11/2001
• Est. Priority Date: 05/29/1997
• Status: Expired due to Term

• Current Assignee: Hewlett Packard Enterprise Development LP (Hewlett-Packard Enterprise Company)
• Original Assignee: 3Com Corporation (HP Inc.)
• Inventors: Burns, Lawrence M., Fisher, David A., Muther, Stephen E.
• Primary Examiner(s): Crosland, Donnie L.
• Application Number:
  US09/675,730
• Time in Patent Office: 438 Days
• Field of Search: 340/310.01, 340/310.02, 340/310.08, 455/3.1, 455/3.3, 370/487, 370/490, 370/419, 370/442, 375/257, 375/259, 307/126, 307/127, 307/128
• US Class Current: 307/3
• CPC Class Codes: H04B 2203/5437 Wired telephone
• CPC Class Codes: H04B 2203/5441 Wireless systems or telephone
• CPC Class Codes: H04B 2203/5445 Local network
• CPC Class Codes: H04B 2203/547 via DC power distribution
• CPC Class Codes: H04B 2203/5483 using coupling circuits
• CPC Class Codes: H04B 2203/5491 using filtering and bypassing
• CPC Class Codes: H04B 3/542 the information being in digital form
• CPC Class Codes: H04L 12/10 Current supply arrangements

Abstract

Electrical supply current, sufficient to power a wireless access point, is transmitted concurrently with a network data signal across a transmission line. A power and data coupler couples the network data signal and the power signal, received through a data input and a power input respectively, and transmits the coupled signal, to a distance of three meters or more, over the transmission line to a power and data decoupler. The power and data decoupler separates the power signal from the network data signal and supplies those signals to a power output port and a data output port, respectively, for use by a wireless access node. The power signal may be modulated at a low frequency relative to the frequency of the data signal, and the network data signal has a data transmission rate of one megabit/second or higher.

Claims

1. An apparatus for providing electrical power supply current to a network device, comprising:

a transmission line having a proximal end and a distal end, the distal end coupled to the network device, the transmission line adapted for transmission of a data signal over a distance of greater than 3 meters at a data rate of greater than 1 megabits per second;

a coupler coupled to the proximal end of the transmission line, the coupler having a data port and a power input, the coupler coupling a power supply current from the power input and the data signal from the data port to the transmission line;

at least one center-tapped inductor for isolating the power input from the data port, the at least one center-tapped inductor also coupling the power supply current to the transmission line; and

a decoupler coupled to the distal end of the transmission line, the decoupler having a data output coupled to the network device and a power output coupled to the network device, the decoupler supplying the data signal from the transmission line to the data output and supplying the power supply current from the transmission line to the power output.

2. The apparatus of claim 1, further comprising at least one isolation transformer for isolating the data port from the power input, the at least one isolation transformer also coupling the data port to the transmission line.

3. A system for providing electrical power supply current to at least one network device, comprising:

a transmission line having a proximal end and a distal end, the distal end coupled to the at least one network device;

a coupler coupled to the proximal end of the transmission line, the coupler having a data port and a power input, the coupler coupling a power supply current from the power input and a data signal from the data port to the transmission line;

at least one center-tapped inductor for coupling the power supply current to the transmission line; and

a decoupler coupled to the distal end of the transmission line, the decoupler having a data output coupled to the at least one network device and a power output coupled to the at least one network device, the decoupler supplying the data signal from the transmission line to the data output and supplying the power supply current from the transmission line to the power output.

4. The system of claim 3, further comprising at least one coupler isolation transformer for isolating the data port from the power input, the at least one coupler isolation transformer also coupling the data port to the transmission line, the at least one coupler isolation transformer having a data port side and a transmission line side;

and

at least one coupler blocking capacitor connected in series with the transmission line side.

5. The system of claim 3, further comprising at least one decoupler center-tapped inductor for isolating the power output from the data output, the at least one decoupler center-tapped inductor also coupling the power supply current to the power output.

6. The system of claim 5, further comprising at least one decoupler isolation transformer for isolating the data output from the power supply current, the at least one decoupler isolation transformer also coupling the data output to the transmission line.

7. The system of claim 3, wherein the power supply current is direct current.

8. The system of claim 3, wherein the power supply current is alternating current.

9. The system of claim 4, wherein the at least one coupler isolation transformer comprises partial windings on the transmission line side and the at least one coupler blocking capacitor is connected between the partial windings.

10. The system of claim 3, further comprising at least one series inductor connected between the power input and a center of the at least one center-tapped inductor.

11. For use in a system for providing electrical power supply current to at least one network device, a coupler for coupling a data signal and a power supply current to a transmission line, the coupler comprising:

a data port and a power input, the coupler coupling the power supply current from the power input and coupling the data signal from the data port to the transmission line; and

at least one center-tapped inductor for coupling the power supply current to the transmission line.

12. The coupler of claim 11, further comprising at least one isolation transformer for isolating the data port from the power input, the at least one isolation transformer also coupling the data port to the transmission line;

wherein the at least one isolation transformer includes a data port side and a transmission line side; and

wherein the decoupler includes at least one blocking capacitor connected in series with the transmission line side of the at least one isolation transformer.

13. The coupler of claim 12, wherein the transmission line side of the at least one isolation transformer includes partial windings and the at least one blocking capacitor is connected between the partial windings.

14. The coupler of claim 11, wherein the coupler further comprises at least one series inductor, the at least one series inductor being connected between the power input and a center of the at least one center-tapped inductor.

15. For use in a system for providing electrical power supply current to at least one network device, a coupler for coupling a data signal and a power supply current to a transmission line, the coupler comprising:

a data port and a power input, the coupler coupling the power supply current from the power input and coupling the data signal from the data port to the transmission line;

two isolation transformers for isolating the data port from the power input, the two isolation transformers also coupling the data port to the transmission line;

two center-tapped inductors for coupling the power supply current to the transmission line;

wherein the two isolation transformers each have a data port side and a transmission line side.

16. The coupler of claim 15, wherein the coupler further comprises two blocking capacitors, each blocking capacitor being connected in series with the transmission line side of a different one of the two isolation transformers.

17. The coupler of claim 16, wherein each of the two blocking capacitors are connected between partial windings on the transmission line side of a different one of the two isolation transformers.

18. The coupler of claim 15, wherein the coupler further comprises two series inductors, each series inductor being connected between the power input and a center of a different one of the two center-tapped inductors.

19. For use in a system for providing electrical power supply current to at least one network device, a decoupler for decoupling a data signal and a power supply current from a transmission line, the decoupler comprising:

an input port for receiving the data signal and the power supply current from the transmission line;

a power output for transmitting the power supply current;

a data output for transmitting the data signal; and

at least one center-tapped inductor for transmitting the power supply current to the power output.

20. The decoupler of claim 19, further including at least one isolation transformer for isolating the data output from the power output, the at least one isolation transformer also coupling the data output to the transmission line;

wherein the at least one isolation transformer has a data output side and a transmission line side; and

wherein the decoupler includes at least one blocking capacitor connected in series with the transmission line side of the at least one isolation transformer.

21. The decoupler of claim 20, wherein the transmission line side of the at least one isolation transformer includes partial windings and the at least one blocking capacitor is connected between the partial windings.

22. The decoupler of claim 19, wherein the decoupler further comprises at least one series inductor, the at least one series inductor being connected between the power output and a center of the at least one center-tapped inductor.

23. For use in a system for providing electrical power supply current to at least one network device, a decoupler for decoupling a data signal and a power supply current from a transmission line, the decoupler comprising:

an input port for receiving the data signal and the power supply current from the transmission line;

a power output for transmitting the power supply current;

a data output for transmitting the data signal;

two isolation transformers for isolating the data output from the power output, the two isolation transformers also coupling the data output to the transmission line;

wherein the two isolation transformers each have a data output side and a transmission line side;

two center-tapped inductors for coupling the power supply current to power output.

24. The decoupler of claim 23, wherein the decoupler further comprises two blocking capacitors, each blocking capacitor being connected in series with the transmission line side of a different one of the two isolation transformers.

25. The decoupler of claim 24, wherein each of the two isolation transformers includes partial windings on the transmission line side and wherein the blocking capacitors are connected between the partial windings.

26. The decoupler of claim 23, wherein the decoupler further comprises two series inductors, each series inductor being connected between the power output and a center of a different one of the two center-tapped inductors.