Optical connection arrangements

• US 20020191899A1
• Filed: 06/15/2001
• Published: 12/19/2002
• Est. Priority Date: 06/15/2001
• Status: Active Grant

• Current Assignee: RPX Corporation
• Original Assignee: Tropic Networks, Inc. (Nokia Corporation)
• Inventors: Kelly, Colin Geoffrey, Bierman, Robert Michael
• Granted Patent: US 6,674,935 B2
• Time in Patent Office: Days
• US Class Current: 385/24
• CPC Class Codes: H04J 14/0206 Express channels arrangements
• 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 14/0219 Modular or upgradable architectures

Abstract

An optical connection arrangement is provided in an optical path to facilitate changing optical add/drop multiplexer (OADM) and other optical component modules while optical traffic is present on the optical path, with minimal interruption to such traffic. The connection arrangement has a plurality of optical ports to each of which an optical component can be coupled, and one or more optical switches which can be controlled to selectively include in the optical path or bypass each optical port. Such connection arrangements can be coupled in series and/or in parallel for convenient modular add/drop configurations and for opposite directions of transmission of optical traffic on respective optical paths.

Claims

1. An optical connection arrangement comprising:

a plurality of optical ports each comprising at least two optical connections for respectively supplying an optical signal to and receiving an optical signal from an optical component coupled to the respective port;

an optical signal input;

an optical signal output; and

at least one optical switch coupled to the optical signal input, the optical signal output, and the plurality of optical ports, the optical switch being controllable to provide an optical path from the optical signal input to the optical signal output selectively via none, one, or at least two of the plurality of optical ports.

2. An optical connection arrangement as claimed in claim 1 and including at least one optical add/drop multiplexer coupled to a respective one of the optical ports.

3. An arrangement comprising two optical connection arrangements each as claimed in claim 1, the optical signal output of one optical connection arrangement being coupled to the optical signal input of the other optical connection arrangement.

4. An optical connection arrangement as claimed in claim 1 wherein the optical switch comprises an N×

N optical switch having N optical inputs and N optical outputs, where N is an integer greater than 2, which is controllable to selectively connect each of its inputs to any of its outputs, the optical signal input is coupled to one input of the optical switch, the optical signal output is coupled to one output of the optical switch, and each optical port has two optical connections coupled to a respective output and to a respective input of the optical switch for respectively supplying an optical signal to and receiving an optical signal from an optical component coupled to the respective port.

5. An optical connection arrangement as claimed in claim 4 and including at least one optical add/drop multiplexer coupled to a respective one of the optical ports.

6. An arrangement comprising two optical connection arrangements each as claimed in claim 4, the optical signal output of one optical connection arrangement being coupled to the optical signal input of the other optical connection arrangement.

7. An optical connection arrangement as claimed in claim 6 and including at least one optical drop filter coupled to a respective one of the optical ports of said one optical connection arrangement and at least one optical add filter coupled to a respective one of the optical ports of said other optical connection arrangement.

8. An optical connection arrangement as claimed in claim 1 wherein each optical port has an optical connection to one of two optical outputs of a preceding optical switch stage, and an optical connection to one of two inputs of a following switch stage, the optical switch stages constituting said at least one optical switch, a first one of said optical switch stages having an optical input coupled to said optical signal input and a last one of said optical switch stages having an optical output coupled to said optical signal output, the arrangement further comprising an optical coupling from another of the two optical outputs of each said preceding optical switch stage to another of the two inputs of the respective following switch stage for optically bypassing the respective optical port, each optical switch stage having two optical connection states between its input(s) and its output(s), the optical switch stages being controllable to include selectively each optical port in, or selectively exclude it from, an optical path from said optical signal input to said optical signal output.

9. An optical connection arrangement as claimed in claim 8 wherein at least one of the optical switch stages comprises a 2×

2 optical switches.

10. An optical connection arrangement as claimed in claim 8 wherein at least one of the optical switch stages comprises two 1×

2 optical switches coupled in series to provide two optical inputs and two optical outputs.

11. An optical connection arrangement as claimed in claim 8 wherein there are at least three optical ports and at least four optical switch stages.

12. An optical connection arrangement as claimed in claim 8 and including at least one optical add/drop multiplexer coupled to a respective one of the optical ports.

13. An arrangement comprising two optical connection arrangements each as claimed in claim 8, the optical signal output of one optical connection arrangement being coupled to the optical signal input of the other optical connection arrangement.

14. An arrangement as claimed in claim 13 and including a further optical port having two optical connections, for respectively supplying an optical signal to and receiving an optical signal from an optical component coupled to the further optical port, coupled respectively to a second output of said last one of the optical switch stages of said one optical connection arrangement and to a second input of said first one of the optical switch stages of said other optical connection arrangement.

15. An arrangement comprising two optical connection arrangements each as claimed in claim 8, for two opposite directions of transmission of optical signals, the plurality of optical ports being common to the two optical connection arrangements and each optical port comprising four optical connections for respectively supplying an optical signal to and receiving an optical signal from an optical component for each direction of transmission coupled to the respective port.

16. An arrangement as claimed in claim 15 and including at least one pair of optical add/drop multiplexers coupled to a respective one of the optical ports.

17. An optical arrangement comprising two arrangements each as claimed in claim 15 and coupled in series with one another for the two opposite directions of transmission of optical signals.

18. An arrangement as claimed in claim 17 and including a further optical port between the series-coupled optical connection arrangements, the further optical port having four optical connections coupled respectively to second outputs of said last one of the optical switch stages for the two opposite directions of transmission, and second inputs of said first one of the optical switch stages for the two opposite directions of transmission, of the respective optical connection arrangements.

19. An optical add/drop multiplexer (OADM) arrangement comprising:

an optical connection arrangement in an optical path, the optical connection arrangement comprising at least one optical switch and a plurality of optical ports each of which can be selectively included in the optical path or bypassed by control of said at least one optical switch, the optical ports each being arranged for coupling of an OADM thereto so that different OADMs can be coupled each to any of said plurality of optical ports; and

at least one OADM optically coupled to a respective optical port of the optical connection arrangement.

20. A method of modifying optical couplings of one or more optical components to an optical path, comprising the steps of:

providing in the optical path an optical connection arrangement having a plurality of optical ports each of which can be selectively included in the optical path or bypassed by control of at least one optical switch of the optical connection arrangement;

changing optical couplings of at least one optical component to a respective optical port while the optical connection arrangement is controlled to selectively bypass the respective optical port; and

subsequently controlling the optical connection arrangement to selectively include the respective optical port and said optical component in the optical path.