Reconfigurable multiwavelength network elements

• US 6,272,154 B1
• Filed: 10/30/1998
• Issued: 08/07/2001
• Est. Priority Date: 10/30/1998
• Status: Expired due to Fees

• Current Assignee: Rembrandt Communications LP (Rembrandt IP Management, LLC)
• Original Assignee: Tellium, Inc. (DZS, Inc.)
• Inventors: Gamelin, John, Brackett, Charles A., Bala, Krishna, Tomlinson, W. John
• Primary Examiner(s): Chin, Wellington
• Assistant Examiner(s): JONES, PRENELL P
• Application Number:
  US09/182,644
• Time in Patent Office: 1,012 Days
• Field of Search: 370/535, 370/222, 370/395, 370/127, 455/600, 455/601, 455/617, 455/607, 359/128, 359/134, 359/139, 359/341, 359/119, 359/110
• US Class Current: 370/535
• CPC Class Codes: H04J 14/0206 Express channels arrangements
• 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 14/0227 Operation, administration, maintenance or provisioning [OAMP] of WDM networks, e.g. media access, routing or wavelength allocation
• CPC Class Codes: H04J 14/0241 Wavelength allocation for communications one-to-one, e.g. unicasting wavelengths
• CPC Class Codes: H04J 14/0283 WDM ring architectures
• CPC Class Codes: H04J 14/0293 Optical channel protection
• CPC Class Codes: H04J 14/0297 Optical equipment protection
• CPC Class Codes: H04Q 11/0062 Network aspects
• CPC Class Codes: H04Q 2011/0016 using wavelength multiplexing or demultiplexing
• CPC Class Codes: H04Q 2011/0073 Provisions for forwarding or routing, e.g. lookup tables
• CPC Class Codes: H04Q 2011/0092 Ring

Abstract

A reconfigurable multiwavelength network element includes a first demultiplexer unit for demultiplexing a first multiplexed optical signal from a first optical fiber into a first plurality of optical outputs; a second demultiplexer unit for demultiplexing a second multiplexed optical signal from a second optical fiber into a second plurality of optical outputs; a first multiplexer unit having first optical inputs for receiving signals to be multiplexed together; a second multiplexer unit having second optical inputs for receiving signals to be multiplexed together; and a cross-connect unit having first and second portions, the first portion directing signals received from at least a first one of the first plurality of optical outputs and a first one of the second plurality of optical outputs to a first one of the first optical inputs and a first one of the second optical inputs, the second portion directing signals received from at least a second one of the first plurality of optical outputs and a second one of the second plurality of optical outputs to a second one of the first optical inputs and a second one of the second optical inputs.

Claims

1. A reconfigurable multiwavelength network element for a bidirectional network ring having first and second optical paths corresponding to clockwise and counter-clockwise directions, comprising:

a first demultiplexer unit coupled with the first optical path, the first demultiplexer unit having a first input for receiving a first multiwavelength signal over first optical path and having first outputs for outputting at least a first signal and a second signal demultiplexed from the first multiwavelength signal;

a second demultiplexer unit coupled with the second optical path, the second demultiplexer unit having a first input for receiving a second multiwavelength signal over the second optical path and having second outputs for outputting at least a third signal and a fourth signal demultiplexed from the second multiwavelength signal;

a cross-connect unit for optically switching optical signals, wherein the cross-connect unit includes a first receiver to receive the first signal, a second receiver to receive the third signal, and a third receiver to receive a first client add signal, the cross-connect unit directing the first signal the third signal and the first client add signal to first, second, and third transmitters, and wherein the cross-connect unit further includes a fourth receiver to receive the second signal, a fifth receiver to receive the fourth signal, and a sixth receiver to receive a second client add signal, the cross-connect unit directing the second signal, the fourth signal and the second client add signal to fourth, fifth, and sixth transmitters;

a first multiplexer unit interconnected with the third and fourth transmitters to multiplex together the respective signals, wherein the first transmitter provides a first client drop signal; and

a second multiplexer unit interconnected with the second and sixth transmitters to multiplex together the respective signals, wherein the fifth transmitter provides a second client drop signal.

2. The reconfigurable multiwavelength optical network element according to claim 1, wherein the first demultiplexer unit includes a demultiplexer and an optical amplifier.

3. The reconfigurable multiwavelength optical network element according to claim 2, wherein the first demultiplexer unit further includes an second demultiplexer to drop an optical service channel.

4. The reconfigurable multiwavelength optical network element according to claim 2, wherein the demultiplexer unit further includes a tap to provide a sample of the multiwavelength signal to a power monitor.

5. The reconfigurable multiwavelength optical network element according to claim 1, wherein the optical cross-connect unit further includes clock and data recovery circuits.

6. The reconfigurable multiwavelength optical network element according to claim 1, wherein the first multiplexer unit includes a multiplexer and an optical amplifier, the optical amplifier generating a stabilization signal.

7. The reconfigurable multiwavelength optical network element according to claim 6, wherein the first multiplexer unit further includes an second multiplexer to add an optical service channel.

8. The reconfigurable multiwavelength optical network element according to claim 6, wherein the first demultiplexer unit further includes a tap to provide a sample of the multiwavelength signal to a power monitor.

9. The reconfigurable multiwavelength optical network element according to claim 1, wherein the first and second demultiplexer units respectively receive the same number of wavelengths from the first and second optical fibers.

10. The reconfigurable multiwavelength optical network element according to claim 1, wherein the signal switching is provided between the first and second optical fibers in a ring structure network.

14. The network element according to claim 1, wherein path protection is provided when the first optical path is broken by routing signals from the first optical path via the second optical path.

11. A reconfigurable multiwavelength network element, comprising:

a demultiplexer unit for receiving and demultiplexing a multiplexed optical signal, the demultiplexer unit having optical outputs corresponding to channels of the multiplexed signal;

a first multiplexer unit having optical inputs for receiving signals to be multiplexed together; and

a cross-connect unit to direct signals received from the optical outputs and a client add port to the optical inputs and a client drop port.

12. The reconfigurable multiwavelength optical network element according to claim 11, wherein the cross-connect unit includes a cross-connect, a first clock and data recovery circuit, and a second clock and data recovery circuit, the first and second clock and data recovery circuits being before and after the cross-connect.

13. The reconfigurable multiwavelength optical network element according to claim 11, wherein the multiplexer unit includes a clock and data recovery circuit.