Cable System with Active RF Device Powered by RF Energy Converted to DC Power, and Associated Method

• US 20080274691A1
• Filed: 05/02/2007
• Published: 11/06/2008
• Est. Priority Date: 05/02/2007
• Status: Active Grant

• Current Assignee: John Mezzalingua Associates Incorporated
• Original Assignee: John Mezzalingua Associates Incorporated
• Inventors: Shafer, Steve
• Granted Patent: US 8,078,102 B2
• Time in Patent Office: Days
• US Class Current: 455/14
• CPC Class Codes: H04N 7/10 Adaptations for transmission by electrical cable H04N7/12 takes precedence

Abstract

A cable system comprises a main line carrying first RF signals for a plurality of subscribers, and a subscriber line coupled with the main line and carrying the first RF signals between the subscriber'"'"'s facility and the main line and also carrying second RF signals that are different in frequency from the first RF signals. The system further comprises a rectifier/voltage multiplier connected to the subscriber line for converting AC energy in the second RF signals into DC current, and an active RF device powered by the DC current from the rectifier/voltage multiplier, the RF device being located along the subscriber line. The system can include a filter connected between the subscriber line and the rectifier/voltage multiplier for filtering the second RF signals. The rectifier/voltage multiplier can be located either inside or outside the subscriber'"'"'s facility.

Claims

1. A cable system for providing RF signals into a subscriber'"'"'s facility, comprising:

a main line carrying first RF signals for a plurality of subscribers, the first RF signals containing information communicated between the main line and the subscribers;

a subscriber line coupled between the main line and the subscriber'"'"'s facility, the subscriber line carrying the first RF signals and also carrying second RF signals having a frequency different from that of the first RF signals;

a rectifier/voltage multiplier connected to the subscriber line, the rectifier/voltage multiplier converting AC energy in the second RF signals into DC current; and

an active RF device powered by the DC current from the rectifier/voltage multiplier, the RF device being located along the subscriber line.

2. The cable system of claim 1, wherein the main line comprises a trunk line carrying AC power and the first RF signals, and further comprising an RF signal generator coupled with the trunk line and powered by the AC power to generate the second RF signals, and a tap connected to the trunk line and to the RF signal generator, the subscriber line being connected to the tap such that the second RF signals are carried over the subscriber line into the subscriber'"'"'s facility.

3. The cable system of claim 1, further comprising a filter connected between the subscriber line and the rectifier/voltage multiplier for selectively passing the second RF signals to the rectifier/voltage multiplier.

4. The cable system of claim 1, wherein the rectifier/voltage multiplier is located outside the subscriber'"'"'s facility.

5. The cable system of claim 1, wherein the rectifier/voltage multiplier is located inside the subscriber'"'"'s facility.

6. The cable system of claim 1, wherein the RF device comprises an active filter.

7. The cable system of claim 1, wherein the RF device comprises an amplifier.

8. The cable system of claim 1, wherein the RF device comprises an active step attenuator.

9. The cable system of claim 1, wherein the second RF signals originate inside the subscriber'"'"'s facility.

10. The cable system of claim 9, wherein the second RF signals comprise return signals transmitted from a unit in the subscriber'"'"'s facility to the main line.

11. The cable system of claim 10, wherein the second RF signals are generated by a cable modem or converter box located inside the subscriber'"'"'s facility.

12. The cable system of claim 9, wherein the second RF signals comprise ingress noise picked up by the subscriber line from RF equipment located proximate the subscriber'"'"'s facility.

13. A cable system for providing RF signals into a subscriber'"'"'s facility, comprising:

a main line carrying first RF signals for a plurality of subscribers, the first RF signals containing information communicated between the main line and the subscribers;

a subscriber line coupled between the main line and the subscriber'"'"'s facility, the subscriber line carrying the first RF signals;

an antenna proximate the subscriber'"'"'s facility for receiving free-radiated second RF signals;

a rectifier/voltage multiplier connected to the antenna, the rectifier/voltage multiplier converting AC energy in the second RF signals into DC current; and

an active RF device powered by the DC current from the rectifier/voltage multiplier, the RF device being located along the subscriber line.

14. The cable system of claim 13, further comprising a filter connected between the antenna and the rectifier/voltage multiplier for filtering the RF signals received by the antenna.

15. A method for communicating RF signals between a head-end facility and a subscriber'"'"'s facility, comprising the steps of:

transmitting first RF signals between the head-end facility and the subscriber'"'"'s facility via a main line and a subscriber line tapped into the main line, the subscriber line also carrying second RF signals different in frequency from the first RF signals;

rectifying the second RF signals to produce a DC current; and

using the DC current to power an active RF device located along the subscriber line.

16. The method of claim 15, further comprising the step of supplying AC power through the main line but not through the subscriber line, and generating the second RF signals using an RF signal generator powered by the AC power from the main line.

17. The method of claim 15, wherein the second RF signals originate in the subscriber'"'"'s facility.

18. The method of claim 17, wherein the second RF signals comprise return signals sent from a unit in the subscriber'"'"'s facility via the subscriber line and main line to the head-end facility.

19. The method of claim 17, wherein the second RF signals comprise ingress noise that enters the subscriber line.

20. The method of claim 15, wherein the second RF signals are provided by an antenna located proximate the subscriber'"'"'s facility, the antenna receiving free-radiated RF signals and supplying them as the second RF signals to the subscriber line.