Array waveguide grating (AWG)-based optical switching fabrics are receiving increasing attention due to their simplicity and good performance. However, AWGs are affected by coherent crosstalk that can significantly impair system operation when the same wavelength is used simultaneously on several input ports. To permit large port counts in a N × N AWG, a possible solution is to schedule data transmissions across the AWG preventing switch configurations that generate large crosstalk. We study the properties and the existence conditions of switch configurations able to control coherent crosstalk. The presented results show that, by running a properly constrained scheduling algorithm to avoid or minimize crosstalk, it is possible to operate an AWG-based switch with large port counts without significant performance degradation.
Bibliographical noteFunding Information:
Manuscript received September 15, 2009; revised March 31, 2010 and June 12, 2010; accepted June 12, 2010; approved by IEEE/ACM TRANSACTIONS ON NETWORKING Editor T. Bonald. Date of publication August 12, 2010; date of current version February 18, 2011. This work was supported by the BONE-project (“Building the Future Optical Network in Europe”), a Network of Excellence funded by the European Commission through the 7th ICT-Framework Programme. The work of D. Hay was supported by CIAN NSF ERC under Grant EEC-0812072.
- Arrayed waveguide grating (AWG)
- coherent crosstalk
- input-queued switches
- optical switchings
- scheduling algorithms