An Optical Communication System for Transmitting RF Signals Downstream and Bidirectional Telephony Signals Which Also Include RF Control Signals Upstream

• US 20060242682A1
• Filed: 06/05/2006
• Published: 10/26/2006
• Est. Priority Date: 05/11/1999
• Status: Abandoned Application

• Current Assignee: Tellabs Bedford, Inc. (Infinera Corp.)
• Original Assignee: Tellabs Bedford, Inc. (Infinera Corp.)
• Inventors: BuAbbud, George H.
• Application Number:
  US11/422,172
• Publication Number:
  US 20060242682A1
• Time in Patent Office: Days
• US Class Current: 725/129
• CPC Class Codes: H04J 14/0226 Fixed carrier allocation, e.g. according to service
• CPC Class Codes: H04J 14/0232 for downstream transmission
• CPC Class Codes: H04J 14/0247 Sharing one wavelength for at least a group of ONUs
• CPC Class Codes: H04J 14/0252 Sharing one wavelength for at least a group of ONUs, e.g. for transmissions from-ONU-to-OLT or from-ONU-to-ONU
• CPC Class Codes: H04J 14/0282 WDM tree architectures
• CPC Class Codes: H04M 11/062 using different frequency bands for speech and other data
• CPC Class Codes: H04N 2007/1739 the upstream communication being transmitted via a separate link, e.g. telephone line
• CPC Class Codes: H04N 21/6118 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 21/6168 involving cable transmission, e.g. using a cable modem
• CPC Class Codes: H04N 7/10 Adaptations for transmission by electrical cable H04N7/12 takes precedence
• CPC Class Codes: H04N 7/17309 Transmission or handling of upstream communications
• CPC Class Codes: H04N 7/22 Adaptations for optical transmission

Abstract

A method of transmitting TV signals and bidirectional telephone communication signals on a single optical fiber, existing telephone twisted pair infrastructure, and existing coaxial cable infrastructure. In addition to allowing the downstream transmission of television channels as well as bidirectional telephone communication, the single optical fibers also provides for the upstream travel of television related signals while requiring minimal changes of the existing infrastructure.

Claims

1. An optical distribution terminal, comprising:

a laser diode operable to receive an electrical signal, the electrical signal corresponding to a video source signal, the laser diode operable to generate a video optical signal at a first wavelength in response to the electrical signal;

a multiplexer operable to receive the video optical signal at the first wavelength, the multiplexer operable to receive a telephony optical signal at a second wavelength over a first optical fiber, the multiplexer operable to transmit the video and telephony optical signals in their respective first and second wavelengths over a second optical fiber, the multiplexer operable to receive a return video optical signal and a return telephony optical signal at the second wavelength over the second optical fiber, the multiplexer operable to transmit the return video and telephony optical signals at the second wavelength over the first optical fiber.

distribution circuitry for transmitting the received video and telephony signals to a plurality of subscribers and for receiving the telephony return signals and the video return signals from the plurality of subscribers; and

a multiplexer for combining the telephony return signals and the video return signals to generate the multiplexed return signals.

2. The optical distribution terminal of claim 1, wherein the first wavelength is 1550 nm.

3. The optical distribution terminal of claim 1, wherein the second wavelength is 1310 nm.

4. The optical distribution terminal of claim 1, wherein the electrical signal has a bandwidth between about 50 and 800 MHz.

5. The optical distribution terminal of claim 1, further comprising:

an amplifier operable to receive the video optical signal from the laser diode, the amplifier operable to amplify the video optical signal for presentation to the multiplexer.

6. The optical distribution terminal of claim 1, further comprising:

a photodiode operable to convert the return video and telephony optical signals into an electrical signal format.

7. The optical distribution terminal of claim 6, further comprising:

a diplexer operable to split the electrical signal format into a return telephony electrical signal and a return video electrical signal.

8. The optical distribution terminal of claim 7, wherein the return video electrical signal has a bandwidth between about 5 and 50 MHz.

9. The optical distribution terminal of claim 7, wherein the return telephony electrical signal includes plain old telephone service signals.

10. The optical distribution terminal of claim 1, further comprising:

a light splitting circuit operable to receive the video optical signal, the light splitting circuit operable to provide the video optical signal to multiple destinations.

11. A method for transmitting optical signals, comprising:

receiving a video electrical signal;

converting the video electrical signal to a video optical signal having a first wavelength;

receiving a telephony optical signal having a second wavelength;

multiplexing the video optical signal with the telephony optical signal;

transmitting the video optical signal at the first wavelength and the telephony optical signal at the second wavelength over an optical fiber;

receiving return video and telephony optical signals at the second wavelength over the optical fiber.

12. The method of claim 11, wherein the first wavelength is 1550 nm and the second wavelength is 1310 nm.

13. The method of claim 11, wherein the video electrical video signal has a bandwidth of about 50 to 800 MHz.

14. The method of claim 11, further comprising:

extracting video electrical signals and telephony electrical signals from the return video and telephony optical signals.

15. The method of claim 11, further comprising:

amplifying the video optical signal prior to multiplexing with the telephony optical signal.

18. The system of claim 11, wherein the video electrical video signal has a bandwidth of about 50 to 800 MHz.

19. The system of claim 11, further comprising:

means for extracting video electrical signals and telephony electrical signals from the return video and telephony optical signals.

20. The system of claim 11, further comprising:

means for amplifying the video optical signal prior to multiplexing with the telephony optical signal.

16. A system for transmitting optical signals, comprising:

means for receiving a video electrical signal;

means for converting the video electrical signal to a video optical signal having a first wavelength;

means for receiving a telephony optical signal having a second wavelength;

means for multiplexing the video optical signal with the telephony optical signal;

means for transmitting the video optical signal at the first wavelength and the telephony optical signal at the second wavelength over an optical fiber;

means for receiving return video and telephony optical signals at the second wavelength over the optical fiber.

17. The system of claim 16, wherein the first wavelength is 1550 nm and the second wavelength is 1310 nm.