Methods for expanding cross-connect capacity in a ROADM optical network

• US 8,346,089 B2
• Filed: 09/29/2009
• Issued: 01/01/2013
• Est. Priority Date: 09/29/2009
• Status: Active Grant

• Current Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Original Assignee: AT&T Intellectual Property I LP (AT&T, Inc.)
• Inventors: Wisseman, Philip
• Primary Examiner(s): Li, Shi K
• Application Number:
  US12/569,191
• Publication Number:
  US 20110076016A1
• Time in Patent Office: 1,190 Days
• Field of Search: 398 83- 85
• US Class Current: 398/83
• CPC Class Codes: H04J 14/0204 Broadcast and select arrangements, e.g. with an optical splitter at the input before adding or dropping
• CPC Class Codes: H04J 14/0205 Select and combine arrangements, e.g. with an optical combiner at the output after adding or dropping
• CPC Class Codes: H04J 14/0209 Multi-stage arrangements, e.g. by cascading multiplexers or demultiplexers
• CPC Class Codes: H04J 14/0212 using optical switches or wavelength selective switches [WSS]
• CPC Class Codes: H04J 14/0213 Groups of channels or wave bands arrangements
• CPC Class Codes: H04J 14/0217 Multi-degree architectures, e.g. having a connection degree greater than two
• CPC Class Codes: H04J 14/0219 Modular or upgradable architectures

Abstract

A reconfigurable optical add-drop multiplexer (ROADM) transport network comprising a plurality of optical fan-out devices and a first plurality and a second plurality of demultiplexers for locally dropping selected wavelengths; and first plurality and a second plurality of multiplexers for locally adding selected wavelengths, the first and second plurality disposed in a cascaded relationship to enable selective coupling between network degrees.

Claims

1. A system for dynamically adding and dropping wavelengths in a reconfigurable optical add-drop multiplexer transport network comprising:

a plurality of cross-connect modules arranged in a cascaded relationship and connected so as to enable signals input from each of a plurality of network degrees to be switched to another network degree of the plurality of network degrees, each of the plurality of cross-connect modules comprising;

a plurality of multiplexers, each comprising a wavelength selective switch and configured to receive an input signal from a network degree and to output a signal to a network degree; and

a plurality of demultiplexers, each comprising a wavelength selective switch and configured to receive an input signal from a network degree and to output a signal to a network degree.

2. The system of claim 1, further comprising:

an access node comprising;

a plurality of amplifiers;

an input communicatively coupled to one of the plurality of amplifiers;

an output communicatively coupled to one other of the plurality of amplifiers;

a multiplexer;

a demultiplexer;

a power splitter communicatively coupled to the demultiplexer;

an optical combiner; and

a wavelength selective switch communicatively coupled to the multiplexer for adding selected wavelengths.

3. The system of claim 1, wherein each of the plurality of multiplexers and each of the plurality of demultiplexers comprise expansion ports.

4. The system of claim 1, wherein each of the plurality of demultiplexers and each of the plurality of multiplexers comprise one of a power splitter and an optical combiner.

5. A method for dynamically adding and dropping wavelengths in a reconfigurable optical add-drop multiplexer transport network comprising:

receiving signals from a network degree at a plurality of cross-connect modules for dropping selected wavelengths between selected network degrees; and

receiving signals from a network degree at the plurality of cross-connect modules for adding selected wavelengths between selected network degrees;

wherein the plurality of cross-connect modules is arranged in a cascaded relationship and connected to enable signals input from each of a plurality of network degrees to be switched to another network degree of the plurality of network degrees.

6. The method of claim 5, wherein each of the plurality of cross-connect modules comprise a plurality of multiplexers and a plurality of demultiplexers.

7. The method of claim 6, wherein each of the plurality of multiplexers and each of the plurality of demultiplexers comprises expansion ports.

8. The method of claim 6, wherein each of the plurality of demultiplexers and each of the plurality of multiplexers further comprising one of a power splitter and an optical combiner.

9. A system for dynamically adding and dropping wavelengths in a reconfigurable optical add-drop multiplexer transport network comprising:

a plurality of cross-connect modules connected so as to enable signals input from each of a plurality of network degrees to be switched to another network degree of the plurality of network degrees, each of the plurality of cross-connect modules comprising;

a plurality of multiplexers, each comprising a wavelength selective switch and configured to receive an input signal from a network degree and to output a signal to a network degree; and

a plurality of demultiplexers, each comprising a wavelength selective switch and configured to receive an input signal from a network degree and to output a signal to a network degree; and

an access node comprising;

a plurality of amplifiers;

an input communicatively coupled to one of the plurality of amplifiers;

an output communicatively coupled to one other of the plurality of amplifiers;

a multiplexer;

a demultiplexer;

a power splitter communicatively coupled to the demultiplexer;

an optical combiner; and

a wavelength selective switch communicatively coupled to the multiplexer for adding selected wavelengths.

10. The system of claim 9, wherein the plurality of cross-connect modules is arranged in a cascaded relationship.

11. The system of claim 9, wherein each of the plurality of multiplexers and each of the plurality of demultiplexers comprise expansion ports.

12. The system of claim 9, wherein each of the plurality of demultiplexers and each of the plurality of multiplexers comprise one of a power splitter and an optical combiner.