Optical SCM data extraction using a fiber-loop mirror for WDM network systems

We demonstrate the use of a polarization-independent dual-port tilter to ex tract subcarrier multiplexed (SCM) data from a baseband/SCM channel while t he baseband is passed through with minimal distortion. This architecture so lves the fiber dispersion-induced fading problem for SCM channels and elimi nates the complexity of single-sideband modulation techniques by suppressin g the optical carrier at the tap port prior to photodetection, Bit-error-ra te (BER) measurements were performed on the baseband channel showing that t he SCM removal prior to photodetection reduces crosstalk with the subcarrie r channel. The BER on the SCM data shows no effect of dispersion-induced fa ding, The periodic optical frequency characteristic of the filter can be ma tched to the ITU grid, making this tap applicable to multichannel WDM netwo rks.