COHERENT PROBE AND OPTICAL SERVICE CHANNEL SYSTEMS AND METHODS FOR OPTICAL NETWORKS

• US 20130236169A1
• Filed: 04/29/2013
• Published: 09/12/2013
• Est. Priority Date: 12/08/2008
• Status: Active Grant

• Current Assignee: Ciena Corporation
• Original Assignee: Ciena Corporation
• Inventors: Boertjes, David Weldon, Frankel, Michael Y., Blair, Loudon T., Bourget, Christian, Ong, Lyndon Y., Gaudette, Jamie
• Granted Patent: US 9,490,894 B2
• Time in Patent Office: Days
• US Class Current: 398/25
• CPC Class Codes: H04B 10/073 using an out-of-service signal H04B10/071 takes precedence
• CPC Class Codes: H04B 10/0793 Network aspects, e.g. central monitoring of transmission parameters
• CPC Class Codes: H04B 10/0795 Performance monitoring; Measurement of transmission parameters
• CPC Class Codes: H04J 14/0257 Wavelength assignment algorithms
• CPC Class Codes: H04J 14/0267 Optical signaling or routing
• CPC Class Codes: H04J 14/0268 Restoration of optical paths, e.g. p-cycles
• CPC Class Codes: H04J 14/0269 using tables for routing
• CPC Class Codes: H04J 14/0275 using an optical service channel

Abstract

The present disclosure provides dynamic performance monitoring systems and methods for optical networks to ascertain optical network health in a flexible and accurate manner. The present invention introduces accurate estimations for optical channel performance characteristics based either on existing channels or with a dynamic optical probe configured to measure characteristics on unequipped wavelengths. Advantageously, the dynamic performance monitoring systems and methods introduce the ability to determine physical layer viability in addition to logical layer viability.

Claims

1. An optical system, comprising:

a coherent optical transmitter;

a coherent optical receiver; and

a digital processing block connected to the coherent optical transmitter and the coherent optical receiver, wherein the digital processing block selectively operates the coherent optical transmitter and the coherent optical receiver as one of an optical probe and an optical service channel.

2. The optical system of claim 1, wherein the coherent optical transmitter is configured to tune to one of a plurality of wavelengths, and, when operating as the optical probe, the digital processing block determines optical channel performance characteristics of the one of the plurality of wavelengths.

3. The optical system of claim 2, wherein the optical channel performance characteristics comprise any of OSNR measurement, residual Chromatic Dispersion, Polarization Dependent Loss, Polarization Mode Dispersion, inter-channel nonlinear effects, intra-channel nonlinear effects, cross-phase modulation, and bandwidth narrowing.

4. The optical system of claim 2, wherein the digital processing block provides the optical channel performance characteristics to an optical control plane for inclusion in an optical path computation function associated with the optical control plane.

5. The optical system of claim 1, wherein the coherent optical transmitter is configured to tune to an optical service channel wavelength outside an amplification band, and, when operating as the optical service channel, the digital processing block interfaces with the coherent optical transmitter and the coherent optical receive for data transmission.

6. The optical system of claim 5, wherein the data transmission utilizes a low data rate and robust modulation format.

7. The optical system of claim 1, further comprising:

a first optical device connected to the coherent optical receiver and a downstream optical fiber, wherein the first optical coupler is configured to provide an upstream signal to the coherent optical receiver; and

a second optical device connected to the coherent optical transmitter and an upstream optical fiber, wherein the second optical coupler is configured to provide a downstream signal from the coherent optical receiver.

8. The optical system of claim 7, wherein the first optical device and the second optical device each comprise a four port coupler comprising a common in port, a common out port, an OSC add port, and an OSC bypass port.

9. The optical system of claim 1, wherein the coherent optical transmitter and the coherent optical receiver utilize oversampling of a heterodyne intermediate frequency (IF) with adaptive digital filtering.

10. An optical network, comprising:

a plurality of nodes interconnected through a plurality of links;

a control plane communicatively coupled to each of the plurality of nodes; and

a coherent optical system between each of the plurality of nodes selectively operating as one of an optical probe and an optical service channel therebetween;

wherein the control plane comprises an optical path computation function configured to provide estimation of optical channel performance characteristics based on measurements by the optical probe.

11. The optical network of claim 10, wherein the coherent optical system comprises:

a coherent optical transmitter;

a coherent optical receiver; and

a digital processing block connected to the coherent optical transmitter and the coherent optical receiver, wherein the digital processing block selectively operates the coherent optical transmitter and the coherent optical receiver as one of the optical probe and the optical service channel.

12. The optical network of claim 11, wherein the coherent optical transmitter is configured to tune to one of a plurality of wavelengths, and, when operating as the optical probe, the digital processing block determines optical channel performance characteristics of the one of the plurality of wavelengths.

13. The optical network of claim 12, wherein the optical channel performance characteristics comprise any of OSNR measurement, residual Chromatic Dispersion, Polarization Dependent Loss, Polarization Mode Dispersion, inter-channel nonlinear effects, intra-channel nonlinear effects, cross-phase modulation, and bandwidth narrowing.

14. The optical network of claim 12, wherein the digital processing block provides the optical channel performance characteristics to an optical control plane for inclusion in an optical path computation function associated with the optical control plane.

15. The optical network of claim 11, wherein the coherent optical transmitter is configured to tune to an optical service channel wavelength outside an amplification band, and, when operating as the optical service channel, the digital processing block interfaces with the coherent optical transmitter and the coherent optical receive for data transmission.

16. The optical network of claim 15, wherein the data transmission utilizes a low data rate and robust modulation format modulation format.

17. The optical network of claim 11, wherein the coherent optical system further comprises:

a first optical device connected to the coherent optical receiver and a downstream optical fiber, wherein the first optical coupler is configured to provide an upstream signal to the coherent optical receiver; and

a second optical device connected to the coherent optical transmitter and an upstream optical fiber, wherein the second optical coupler is configured to provide a downstream signal from the coherent optical receiver.

18. The optical network of claim 17, wherein the first optical device and the second optical device each comprise a four port coupler comprising a common in port, a common out port, an OSC add port, and an OSC bypass port.

19. The optical network of claim 11, wherein the coherent optical transmitter and the coherent optical receiver utilize oversampling of a heterodyne intermediate frequency (IF) with adaptive digital filtering.

20. A method, comprising:

operating a coherent optical probe between a first node and a second node;

tuning the coherent optical probe to one of a plurality of wavelengths;

measuring optical channel performance characteristics of the one of the plurality of wavelengths utilizing a digital processing block at the second node;

subsequent to the measuring, tuning the coherent optical probe to an optical service channel wavelength; and

operating the coherent optical probe as an optical service channel between the first node and the second node.