Optical communication system

• US 6,580,530 B1
• Filed: 05/28/1999
• Issued: 06/17/2003
• Est. Priority Date: 05/29/1998
• Status: Expired due to Term

• Current Assignee: Cisco Photonics Italy SRL (Cisco Systems, Inc.)
• Original Assignee: Cisco Photonics Italy SRL (Cisco Systems, Inc.)
• Inventors: Sanches, Marcos Antonio Brandão, Loseto, Francesca, Tamburello, Mario, Arecco, Fulvio, Matrona, Piergiovanni
• Primary Examiner(s): Pascal, Leslie
• Assistant Examiner(s): TRAN, DZUNG D
• Application Number:
  US09/321,850
• Time in Patent Office: 1,481 Days
• Field of Search: 359/110, 359/124, 359/143, 359/177, 359/133, 359/119
• US Class Current: 398/5
• CPC Class Codes: H04J 14/0283 WDM ring architectures
• CPC Class Codes: H04J 14/0291 Shared protection at the optical multiplex section (1:1, n:m)
• CPC Class Codes: H04Q 11/0062 Network aspects
• CPC Class Codes: H04Q 2011/0069 using dedicated optical channels
• CPC Class Codes: H04Q 2011/0081 Fault tolerance; Redundancy; Recovery; Reconfigurability
• CPC Class Codes: H04Q 2011/0083 Testing; Monitoring

Abstract

An optical communication system for communicating at least a first optical system. The optical communication system includes a first primary guided optical path and a first secondary guided optical path, through each of which the first optical signal is configured to propagate. A first primary optical amplifier is provided in the first primary guided optical path and is configured to transmit an overmodulation frequency of the first optical signal. A first secondary optical amplifier is provided in the first secondary guided optical path and is configured to transmit the overmodulation frequency of the first optical signal. A controller controls propagation of the first optical signal from the first primary guided optical path to the first secondary guided optical path based on the detected presence of the overmodulation frequency.

Claims

1. An optical communication system for communicating at least a first optical signal comprising:

a first primary guided optical path through which the first optical signal is configured to propagate;

a first secondary guided optical path through which the first optical signal is configured to propagate;

a first primary optical amplifier provided in the first primary guided optical path and configured to transmit an overmodulation frequency of the first optical signal;

a first secondary optical amplifier provided in the first secondary guided optical path and configured to transmit the overmodulation frequency of the first optical signal; and

a control configured to control and switch propagation of the first optical signal from the first primary guided optical path to the first secondary guided optical path based on a detected presence of the overmodulation frequency.

2. An optical communication system according to claim 1, wherein the optical communication system further communicates a second optical signal, and further comprising:

a first secondary guided optical path through which the second optical signal is configured to propagate;

a second secondary guided optical path through which the second optical signal is configured to propagate;

a second primary optical amplifier provided in the second primary guided optical path and configured to transmit, at a third predetermined command, a second overmodulation frequency of the second optical signal;

a second secondary optical amplifier provided in the second secondary guided optical path and configured to transmit, at a fourth predetermined command, the second overmodulation frequency of the second optical signal; and

wherein the control is further configured to control and switch propagation of the second optical signal from the second primary guided optical path to the second secondary guided optical path based on a detected presence of the second overmodulation frequency.

3. An optical communication system according to claim 2, wherein the second optical signal has a propagation direction opposite to that of the first optical signal.

4. An optical communication system according to claim 3, further comprising a first beam splitter at an input of the first primary guided optical path and the first secondary guided optical path to divide the first optical signal between the first primary guided optical path and the first secondary guided optical path.

5. An optical communication system according to claim 4, wherein the control comprises a first switch at an output of the first primary optical amplifier and the first secondary optical amplifier for switching between outputting the first optical signal from the first primary optical amplifier or from the first secondary optical amplifier based on the detected presence of the overmodulation frequency.

6. An optical communication system according to claim 4, further comprising a second beam splitter at an input of the second primary guided optical path and the second secondary guided optical path to divide the second optical signal between the second primary guided optical path and the second secondary guided optical path.

7. An optical communication system according to claim 6, wherein the control comprises a second switch at an output of the second primary optical amplifier and the second secondary optical amplifier for switching between outputting the second optical signal from the second primary optical amplifier or from the second secondary optical amplifier based on the detected presence of the second overmodulation frequency.

8. An optical communication system according to claim 3, wherein the control comprises a first primary receiving amplifier in the first primary guided optical path connected to an output of the first primary optical amplifier and a first secondary receiving amplifier in the first secondary guided optical path connected to an output of the first secondary optical amplifier, and wherein the first primary receiving amplifier and the first secondary receiving amplifier are configured to be disabled by control signals based on the detected presence of the overmodulation frequency.

9. An optical communication system according to claim 8, wherein the control comprises a second primary receiving amplifier in the second primary guided optical path connected to an output of the second primary optical amplifier and a second secondary receiving amplifier in the second secondary guided optical path connected to an output of the second secondary optical amplifier, and wherein the second primary receiving amplifier and the second secondary receiving amplifier are configured to be disabled by control signals based on the detected presence of the second overmodulation frequency.

10. An optical communication system according to claim 3, further comprising a first optical coupler at an output of the first primary guided optical path and the first secondary guided optical path.

11. An optical communication system according to claim 10, further comprising a second optical coupler at an output of the second primary guided optical path and the second secondary guided optical path.

12. An optical communication system according to claim 3, wherein the control comprises a first switch at an output of the first primary guided optical path and the first secondary guided optical path for switching between outputting the first optical signal from the first primary guided optical path or from the first secondary guided optical path based on the detected presence of the overmodulation frequency.

13. An optical communication system according to claim 12, wherein the control comprises a second switch at an input of the first primary optical amplifier and the first secondary optical amplifier for switching between inputting the first optical signal to the first primary optical amplifier or to the first secondary optical amplifier based on the detected presence of the overmodulation frequency.

14. An optical communication system according to claim 12, wherein the control comprises a second switch at an output of the second primary guided optical path and the second secondary guided optical path for switching between outputting the second optical signal from the second primary guided optical path or from the second secondary guided optical path based on the detected presence of the second overmodulation frequency.

15. An optical communication system according to claim 14, wherein the control comprises a third switch at an input of the first primary optical amplifier and the first secondary optical amplifier for switching between inputting the first optical signal to the first primary optical amplifier or to the first secondary optical amplifier based on the detected presence of the first overmodulation frequency.

16. An optical communication system according to claim 15, wherein the control comprises a fourth switch at an input of the second primary optical amplifier and the second secondary optical amplifier for switching between inputting the second optical signal to the second primary optical amplifier or to the second secondary optical amplifier based on the detected presence of the second overmodulation frequency.

17. An optical communication system according to claim 1, wherein the control comprises a first primary receiving amplifier in the first primary guided optical path connected to an output of the first primary optical amplifier and a first secondary receiving amplifier in the first secondary guided optical path connected to an output of the first secondary optical amplifier, and wherein the first primary receiving amplifier and the first secondary receiving amplifier are configured to be disabled by control signals based on the detected presence of the overmodulation frequency.

18. An optical communication system according to claim 1, further comprising an optical coupler at an output of the first primary guided optical path and the first secondary guided optical path.

19. An optical communication system according to claim 1, wherein the control comprises a first switch at an output of the first primary guided optical path and the first secondary guided optical path for switching between outputting the first optical signal from the first primary guided optical path or from the first secondary guided optical path based on the detected presence of the overmodulation frequency.

20. An optical communication system according to claim 19, wherein the control comprises a second switch at an input of the first primary optical amplifier and the first secondary optical amplifier for switching between inputting the first optical signal to the first primary optical amplifier or to the first secondary optical amplifier based on the detected presence of the overmodulation frequency.