SYSTEMS AND METHODS OF OPTICAL PATH PROTECTION FOR DISTRIBUTED ANTENNA SYSTEMS

• US 20070264009A1
• Filed: 04/28/2006
• Published: 11/15/2007
• Est. Priority Date: 04/28/2006
• Status: Active Grant

• Current Assignee: CommScope Technologies, LLC (CommScope Holding Company, Inc.)
• Original Assignee: ADC Telecommunications Incorporated (TE Connectivity Limited)
• Inventors: Sabat, John Jr., Hebert, Thomas
• Granted Patent: US 7,805,073 B2
• Time in Patent Office: Days
• US Class Current: 398/5
• CPC Class Codes: H04B 10/1127 using two distinct parallel optical paths
• CPC Class Codes: H04B 10/25752 Optical arrangements for wireless networks

Abstract

Systems and methods for optical path protection for distributed antenna systems are provided. In one embodiment, a method is provided. The method comprises receiving an electrical uplink radio frequency signal; generating an uplink optical signal derived from the electrical uplink radio frequency signal; splitting the uplink optical signal for transmission on a primary uplink optical fiber and a secondary uplink optical fiber; combining any downlink optical signal received on a primary downlink optical communication medium and any downlink optical signal received on a second downlink optical communication medium in order to output a downlink optical signal; and generating a downlink radio frequency signal derived from the downlink optical signal.

Claims

1. A system comprising:

a hub;

at least one remote node that is located remotely from the hub;

wherein the hub communicates with the at least one remote node via either one of a primary fiber path and a backup fiber path, the primary fiber path comprising an uplink fiber and a downlink fiber and the backup fiber path comprising an uplink fiber and a downlink fiber;

wherein the at least one remote node is coupled to the downlink fiber of the primary fiber path and the downlink fiber of the backup fiber path via an optical combiner;

wherein the at least one remote node is further coupled to the uplink fiber of the primary fiber path and the uplink fiber of the backup fiber path via an optical splitter; and

wherein the hub switches from communicating with the at least one remote node on the primary fiber path to communicating with the at least one remote node on the backup fiber path based on an uplink optical signal received from the at least one remote node.

2. The system of claim 1, wherein when the hub detects a loss of the uplink optical signal from the uplink fiber of the primary fiber path, the hub switches from communicating with the at least one remote node on the primary fiber path to communicating with the at least one remote node on the backup fiber path.

3. The system of claim 1, wherein when the hub detects a loss of the uplink optical signal from the uplink fiber of the backup fiber path, the hub switches from communicating with the at least one remote node on the backup fiber path to communicating with the at least one remote node on the primary fiber path.

4. The system of claim 1, wherein the uplink optical signal comprises multiple wavelength optical signals.

5. The system of claim 1, wherein one or both of the optical combiner and the optical splitter are located external to the at least one remote node.

6. The system of claim 1, wherein one or both of the primary fiber path and the backup fiber path comprises a plurality of uplink fibers.

7. The system of claim 1, wherein one or both of the primary fiber path and the backup fiber path comprises a plurality of downlink fibers.

8. The system of claim 1, wherein the at least one remote node is adapted to determine a signal quality of a downlink optical signal received from the downlink fiber of one or the primary fiber path and the backup fiber path;

and

wherein the at least one remote node is further adapted to communicate the signal quality of the downlink optical signal to the hub.

9. The system of claim 8, wherein the at least one remote node is further adapted to determine one or both of the bit error rate of the downlink optical signal and the optical power level of the downlink optical signal.

10. The system of claim 8, wherein the at least one remote node is further adapted to alert the hub of an inadequate signal quality of the downlink optical signal by disabling the uplink optical signal.

11. The system of claim 8, wherein when the at least one remote node communicates to the hub that the signal quality of the downlink optical signal from the primary fiber path is inadequate, the hub switches from communicating with the at least one remote node on the primary fiber path to communicating with the at least one remote node on the backup fiber path.

12. The system of claim 8, wherein when the at least one remote node communicates to the hub that the signal quality of the downlink optical signal from the backup fiber path is inadequate, the hub switches from communicating with the at least one remote node on the backup fiber path to communicating with the at least one remote node on the primary fiber path.

13. The system of claim 8, wherein the downlink optical signal comprises multiple wavelength optical signals.

14. The system of claim 1, wherein the hub is adapted to determine a signal quality of an uplink optical signal received from the uplink fiber of one of the primary fiber path and the backup fiber path;

wherein when the uplink optical signal received from the uplink fiber of the primary fiber is inadequate, the hub is adapted to switch from communicating with the at least one remote node on the primary fiber path to communicating with the at least one remote node on the backup fiber path;

wherein when the uplink optical signal received from the uplink fiber of the backup fiber is inadequate the hub switches from communicating with the at least one remote node on the backup fiber path to communicating with the at least one remote node on the primary fiber path.

15. The system of claim 14, wherein the at least one remote node is further adapted to determine the bit error rate of the downlink optical signal.

16. A remote node comprising:

an interface by which an uplink radio frequency signal is received at the remote node and from which a downlink radio frequency is output;

an optical transceiver communicatively coupled to the interface to output an uplink optical signal derived from the uplink radio frequency signal and to receive a downlink optical signal;

a splitter to couple the optical transceiver to a primary uplink optical communication medium and a second uplink optical communication medium in order to communicate the uplink optical signal on the primary uplink optical communication medium and the second uplink optical communication medium; and

a combiner to couple the optical transceiver to a primary downlink optical communication medium and a second downlink optical communication medium, wherein the combiner combines any optical signal received on the primary downlink optical communication medium and any optical signal received on the second downlink optical communication medium to output the downlink optical signal;

wherein the optical transceiver outputs a downlink electrical signal derived from the downlink optical signal, wherein the downlink radio frequency signal is derived from the downlink electrical signal.

17. The remote node of claim 16, wherein one or both of the downlink optical signal and the uplink optical signal comprise multiple wavelength optical signals.

18. The remote node of claim 16, wherein the optical transceiver communicates information indicative of an attribute of the downlink optical signal through the uplink optical signal.

19. The remote node of claim 16, wherein one or both of the uplink radio frequency signal and the downlink radio frequency signal comprises an analog radio frequency signal.

20. The remote node of claim 16, wherein one or both of the primary downlink optical communication medium and the second downlink optical communication medium communicate the downlink optical signal via an analog transport;

and

one or both of the primary uplink optical communication medium and the second uplink optical communication medium communicate the uplink optical signal via an analog transport.

21. The remote node of claim 16, wherein one or both of the uplink radio frequency signal and the downlink radio frequency signal comprises a digital radio frequency signal.

22. The remote node of claim 16, wherein one or both of the primary downlink optical communication medium and the second downlink optical communication medium communicate the downlink optical signal via a digital transport;

and

wherein one or both of the primary uplink optical communication medium and the second uplink optical communication medium communicate the uplink optical signal via a digital transport.

23. A method comprising:

receiving an electrical uplink radio frequency signal;

generating an uplink optical signal derived from the electrical uplink radio frequency signal;

splitting the uplink optical signal for transmission on a primary uplink optical fiber and a secondary uplink optical fiber;

combining any downlink optical signal received on a primary downlink optical communication medium and any downlink optical signal received on a second downlink optical communication medium in order to output a downlink optical signal; and

generating a downlink radio frequency signal derived from the downlink optical signal.

24. The method of claim 23, wherein the uplink radio frequency signal is received from an antenna.

25. The method of claim 23, wherein the downlink radio frequency signal is output to an antenna.

26. The method of claim 23, wherein one or both of the downlink optical signal and the uplink optical signal comprise multiple wavelength optical signals.

27. The method of claim 23, further comprising communicating information indicative of an attribute of the downlink optical signal to a hub.

28. The method of claim 23, switching from transmitting a downlink optical signal on the primary downlink optical fiber to transmitting a downlink optical signal on the secondary primary optical fiber based on information indicative of an attribute of the downlink optical signal.

29. An apparatus comprising:

means for receiving an electrical uplink radio frequency signal;

means for generating an uplink optical signal derived from the electrical uplink radio frequency signal;

means for splitting the uplink optical signal for transmission on a primary uplink optical fiber and a secondary uplink optical fiber;

means for combining any downlink optical signal received on the primary downlink optical communication medium and any downlink optical signal received on the second downlink optical communication medium in order to output a downlink optical signal; and

means for generating a downlink radio frequency signal derived from the downlink optical signal.

30. The apparatus of claim 29, wherein one or both of the downlink optical signal and the uplink optical signal comprise multiple wavelength optical signals.

31. A method comprising:

transmitting a downlink optical signal to a downlink fiber of one of a first fiber path and a second fiber path;

combining any downlink optical signal received on the downlink fiber of the first fiber path and any downlink optical signal received on the downlink fiber of the second fiber path in order to output the downlink optical signal;

splitting an uplink optical signal for transmission on an uplink fiber of the first fiber path and an uplink fiber of the second fiber path;

determining a signal quality of the downlink optical signal;

determining a signal quality of the uplink optical signal;

switching between a normal state and backup state based on one or both of the signal quality of the uplink optical signal and the signal quality of the downlink optical signal.

32. The method of claim 31, wherein determining a signal quality of the downlink optical signal further comprises transmitting a signal quality indication via the uplink optical signal when the signal quality of the downlink optical signal is inadequate.

33. The method of claim 31, wherein determining a signal quality of the downlink optical signal further comprises disabling transmission of the uplink optical signal when the signal quality of the downlink optical signal is inadequate.

34. The method of claim 31, wherein determining a signal quality of the downlink optical signal further comprises calculating one or both of the bit error rate of the downlink optical signal and the optical power level of the downlink optical signal.

35. The method of claim 31, wherein determining a signal quality of the uplink optical signal further comprises calculating one or both of the bit error rate of the uplink optical signal and the optical power level of the uplink optical signal.

36. The method of claim 31, wherein one or both of the downlink optical signal and the uplink optical signal comprise multiple wavelength optical signals.

37. A distributed antenna system, the system comprising:

means for combining an optical signal received on a downlink fiber of a first fiber path with an optical signal received on a downlink fiber of a second fiber path in order to output a downlink optical signal;

means for splitting an uplink optical signal for transmission on an uplink fiber of the first fiber path and an uplink fiber of the second fiber path;

means for determining an attribute of the downlink optical signal indicative of the signal quality of the downlink optical signal;

means for determining an attribute of the uplink optical signal indicative of the signal quality of the uplink optical signal; and

means for switching between a normal alignment state and a backup alignment state based on one or both of the attribute of the downlink optical signal and the attribute of the uplink optical signal.

38. The system of claim 37, further comprising:

means for communicating the signal quality of the downlink optical signal via the uplink optical signal.

39. The system of claim 37, wherein one or both of the downlink optical signal and the uplink optical signal comprise multiple wavelength optical signals.

40. The system of claim 37, wherein one or both of the means for combining and the means for splitting are located externally from the means for determining an attribute of the downlink optical signal, the means for determining an attribute of the uplink optical signal and the means for switching.