RECONFIGURABLE BRANCHING UNIT FOR SUBMARINE OPTICAL COMMUNICATION NETWORKS

• US 20130259475A1
• Filed: 04/02/2013
• Published: 10/03/2013
• Est. Priority Date: 04/02/2012
• Status: Active Grant

• Current Assignee: NEC Corporation
• Original Assignee: NEC Corporation, NEC Laboratories America Inc (NEC Corporation)
• Inventors: Ji, Philip N., Aida, Ryuji, Wang, Ting
• Granted Patent: US 9,106,983 B2
• Time in Patent Office: Days
• US Class Current: 398/48
• CPC Class Codes: H04L 12/28 characterised by path configuration, e.g. LAN [Local Area Networks] or WAN [Wide Area Networks] wireless communication networks H04W ; arrangements for dividing the transmission path H04W40/00
• CPC Class Codes: H04Q 11/00 Selecting arrangements for multiplex systems multiplex systems H04J
• CPC Class Codes: H04Q 11/0005 Switch and router aspects
• CPC Class Codes: H04Q 2011/0016 using wavelength multiplexing or demultiplexing

Abstract

Methods and systems for optical communication in a submarine network are provided. An input signal is received from a terminal at a reconfigurable branching unit (BU), and the input signal is split into at least two parts, with one part being associated with one or more trunk terminals and another part being associated with one or more branch terminals. Each of one or more spectrum channels are selected and individually switched to one of a plurality of paths using at least one wavelength selective switch (WSS), with the at least one WSS being configured to transmit the one or more spectrum channels to their respective target output port and to combine signals switched to a specific port into a wavelength division multiplexing (WDM) signal. Individual spectrum channels are filtered out using at least one wavelength blocker (WB).

Claims

1. A method for optical communication comprising:

receiving an input signal from a terminal at a reconfigurable branching unit (BU);

splitting the input signal into at least two parts, with one part being associated with one or more trunk terminals and another part being associated with one or more branch terminals;

selecting and individually switching each of one or more spectrum channels to one of a plurality of paths using at least one wavelength selective switch (WSS), with the at least one WSS being configured to transmit the one or more spectrum channels to their respective target output port;

combining signals switched to a specific port into a wavelength division multiplexing (WDM) signal using the WSS, and sending the WDM signal to an output port; and

filtering out individual spectrum channels using at least one wavelength blocker (WB).

2. The method of claim 1, wherein an optical network is a submarine optical network.

3. The method of claim 1, wherein the input signal is a wavelength division multiplexing (WDM) signal.

4. The method of claim 1, wherein each of the one or more spectrum channels is associated with a dedicated wavelength selective switch (WSS).

5. The method of claim 1, wherein unnecessary dummy light is identified and filtered out using the wavelength selective switch (WSS).

6. The method of claim 1, wherein flexible grid functions are enabled at the reconfigurable branching unit (BU) by employing wavelength division multiplexers (WDM) and wavelength blockers (WB) with flexible grid capability.

7. The method of claim 1, wherein optical power equalization is achieved using the wavelength division multiplexers (WDM) and wavelength blockers (WB).

8. An optical communication system comprising:

a reconfigurable branching unit (BU) configured to receive an input signal from a terminal;

a splitter configured to split the input signal into at least two parts, with one part being associated with one or more trunk terminals and another part being associated with one or more branch terminals;

at least one wavelength selective switch (WSS) configured to select and individually switch each of one or more spectrum channels to one of a plurality of paths,

wherein the at least one WSS is configured to transmit the one or more spectrum channels to their respective target output port,

wherein the at least one WSS is configured to combine signals switched to a specific port into a wavelength division multiplexing (WDM) signal, and to send the WDM signal to an output port; and

at least one wavelength blocker (WB) configured to filter out individual spectrum channels.

9. The system of claim 8, wherein an optical network is a submarine optical network.

10. The system of claim 8, wherein the input signal is a wavelength division multiplexing (WDM) signal.

11. The system of claim 8, wherein a dedicated wavelength selective switch (WSS) is associated with each of the one or more spectrum channels.

12. The system of claim 8, wherein the reconfigurable branching unit (BU) enables flexible grid functions by employing wavelength division multiplexers (WDM) and wavelength blockers (WB) with flexible grid capability.

13. The system of claim 8, wherein the wavelength division multiplexers (WDM) and wavelength blockers (WB) are employed to achieve optical power equalization.

14. A reconfigurable branching unit for underwater optical communication, comprising:

a receiver configured to receive a wavelength division multiplexed (WDM) signal from a terminal;

a splitter configured to split the input signal into at least two parts, with one part being associated with one or more trunk terminals and another part being associated with one or more branch terminals;

at least one wavelength selective switch (WSS) configured to select and individually switch each of one or more spectrum channels to one of a plurality of paths,

wherein the at least one WSS is configured to transmit the one or more spectrum channels to their respective target output port,

wherein the at least one WSS is configured to combine signals switched to a specific port into a wavelength division multiplexing (WDM) signal, and to send the WDM signal to an output port;

at least one wavelength blocker (WB) configured to filter out individual spectrum channels; and

at least one dual bidirectional fiber pair between the branching unit and a branch terminal.

15. The reconfigurable branching unit of claim 14, wherein the input signal is a wavelength division multiplexing (WDM) signal.

16. The reconfigurable branching unit of claim 14, wherein a dedicated wavelength selective switch (WSS) is associated with each of the one or more spectrum channels.

17. The reconfigurable branching unit of claim 14, wherein the wavelength selective switch (WSS) identifies and filters out unnecessary dummy light.

18. The reconfigurable branching unit of claim 14, wherein the reconfigurable branching unit (BU) enables flexible grid functions by employing wavelength division multiplexers (WDM) and wavelength blockers (WB) with flexible grid capability.

19. The reconfigurable branching unit of claim 14, wherein the wavelength division multiplexers (WDM) and wavelength blockers (WB) enable optical power equalization to be achieved.

20. The reconfigurable branching unit of claim 14, wherein the plurality of paths include one or more bidirectional paths between one or more trunk terminals and the branch terminals.