Compact switched-retroreflection-based 2/spl times/2 optical switching fabric for WDM applications

A low-interchannel-crosstalk 2/spl times/2 optical switch is proposed and analyzed. The switch is polarization independent and is based on a novel switch-retroreflection architecture and standard fiber-optic circulators that offer ease in assembly and compact size. Low interchannel crosstalk is accomplished using passive and active noise filters that suppress the leakage noise due to the passive polarization components and the active devices, respectively. Theoretical analysis of the proposed 2/spl times/2 optical switch is performed, and the switch interchannel crosstalk and optical insertion loss is estimated under different conditions. A novel system architecture is also proposed that uses the switched-retroreflection-based 2/spl times/2 optical switch and wavelength-division multiplexers/demultiplexers to form an add-drop wavelength-division-multiplexed filter with reduced component count.