Method and system for band blocking in an optical telecommunication network

• US 8,861,966 B2
• Filed: 09/27/2007
• Issued: 10/14/2014
• Est. Priority Date: 12/07/2006
• Status: Active Grant

• Current Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Inventors: Zhu, Fei, Bai, Yu Sheng
• Primary Examiner(s): DOBSON, DANIEL G
• Application Number:
  US11/863,226
• Publication Number:
  US 20080138066A1
• Time in Patent Office: 2,574 Days
• Field of Search: 398 45- 57, 398/79, 398/83
• 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 14/0221 Power control, e.g. to keep the total optical power constant
• CPC Class Codes: H04J 14/02216 by gain equalization

Abstract

Method and system for band blocking in an optical telecommunication network. According to an embodiment, the present invention provides a system for optical network. The system includes an input that is configured to receive an input signal through a first optical input. The system also includes a band splitting module that is coupled to the input. The band splitting module is configured to separate the input signal into a plurality of bands. The plurality of bands includes a first band and a second band. The first band includes a first plurality of wave channels. The first plurality of wave channels is characterized by a first channel spacing. The second band includes a second plurality of wave channels, which is characterized by a second channel spacing.

Claims

1. A system for an optical network, the system comprising:

an input configured to receive an input signal through a first optical input;

a band splitting module, the band splitting module coupled to the input, the band splitting module configured to separate the input signal into a plurality of bands, the plurality of bands including a first band and a second band, the first band including a first plurality of wave channels, the first plurality of wave channels having a first channel spacing, the second band including a second plurality of wave channels, the second plurality of wave channels having a second channel spacing different from the first channel spacing, and wherein the band splitting module outputs the first band and the second band and wherein the first band and the second band output from the band splitting module do not overlap each other;

a plurality of switches, each switch configured to turn off or on each respective one of the plurality of bands;

a band recombining module, the band recombining module configured to couple the plurality of bands; and

an output coupled to the band recombining module, the output configured to provide an output signal, the output signal being a combination of the plurality of bands.

2. The system of claim 1 wherein the plurality of bands includes a third band, the third band having a third channel spacing, the third channel spacing being equal to the first channel spacing.

3. The system of claim 1 is a DWDM system.

4. The system of claim 1 wherein the band recombining module includes a plurality of filters.

5. The system of claim 1 wherein the band recombining module includes a plurality of filters, the plurality of filters having a series configuration.

6. The system of claim 1 wherein the band recombining module includes a plurality of couplers.

7. The system of claim 1 wherein the band recombining module includes a plurality of filters, the plurality of filters having a cascade configuration.

8. The system of claim 1 wherein each of the plurality of switches comprises a variable optical attenuator.

9. The system of claim 8 wherein the variable optical attenuator is capable of tuning greater than or at 40 dB.

10. The system of claim 1 wherein the first channel spacing is approximately 25 GHz.

11. The system of claim 1 wherein the second channel spacing is approximately 50 GHz.

12. The system of claim 1 wherein the band splitting module comprises a plurality of filters, the filters connected in series.

13. The system of claim 1 wherein the band splitting module comprises a plurality of filters, the filters connected in a cascade configuration.

14. The system of claim 1 wherein the band splitting module comprises a plurality of couplers.

15. The system of claim 1 wherein the band splitting module comprises a plurality of TFF-based filters.

26. The system of claim 1 further comprising:

a plurality of wavelength blockers corresponding to the plurality of switches and disposed between the plurality of switches and the recombining module.

16. A system for an optical network, the system comprising:

an input configured to receive a first input signal through a first optical input;

a band splitting module, the band splitting module coupled to the input, the band splitting module configured to separate the input signal into a plurality of bands, the band splitting module including a first filter and a second filter, the plurality of bands including a first band and a second band, the first filter being configured to separate the input signal into the first band and a second input signal, the second filter being configured to separate the second input signal into the second band and a third input signal, the first band including a first plurality of wave channels, the first plurality of wave channels having a first channel spacing, the second band including a second plurality of wave channels, the second plurality of wave channels having a second channel spacing different from the first channel spacing, and wherein the band splitting module outputs the first band and the second band and wherein the first band and the second band output from the band splitting module do not overlap each other;

a plurality of switches, each switch configured to turn off or on each respective one of the plurality of bands;

a band recombining module, the band recombining module configured to couple the plurality of bands; and

an output coupled to the band recombining module.

17. The system of claim 16 wherein the first filter and the second filter are TFF-based filters.

18. The system of claim 16 wherein the first filter and the second filter are in a cascade configuration.

19. The system of claim 16 wherein the band recombining module comprises a plurality of couplers.

20. The system of claim 16 wherein the band recombining module comprises a third filter and a fourth filter, the third filter being a reverse of the first filter.

21. A method for optical providing band blocking, the method comprising:

receiving a first input optical signal;

splitting the first input optical signals into a predetermined number of bands, the bands including a first band and a second band, the first band including a first plurality of wave channels, the first plurality of wave channels having a first channel spacing, the second band including a second plurality of wave channels, the second plurality of wave channels having a second channel spacing different from the first channel spacing, and outputting the first band and the second band wherein the first band and the second band do not overlap each other;

controlling the first band by turning off or on the first band using a first switch;

controlling the second band by turning off or on the second band using a second switch;

coupling the bands into an output; and

providing the output.

22. The method of claim 21 wherein the first channel spacing is approximately 25 GHz.

23. The method of claim 21 wherein the first switch comprises a first variable optical attenuator (VOA) and the second switch comprises a second VOA.

24. The method of claim 23 wherein the first VOA adjusts attenuation of the first band and the second VOA adjusts attenuation of the second band.

25. The method of claim 21 further obtaining a first channel from the first band.

27. A system for an optical network, the system comprising:

an input configured to receive an input signal through a first optical input;

a band splitting module, the band splitting module coupled to the input and configured to separate the input signal into a first band and a second band, the first band including a first plurality of wave channels having a first channel spacing, the second band including a second plurality of wave channels having a second channel spacing different from the first channel spacing;

a plurality of switches, each switch being configured to turn off or on each respective one of the first and second bands;

a plurality of wavelength blockers corresponding to the plurality of switches and disposed between the plurality of switches and a band recombining module, wherein the band recombining module is configured to couple the first band and the second band; and

an output coupled to the band recombining module, wherein the output is configured to provide an output signal comprising a combination of the first band and second band.