Low-crosstalk and compact optical add-drop multiplexer using a multiport circulator and fiber Bragg gratings

Three kinds of low-crosstalk and compact optical add-drop multiplexers (OAD Ms) based on a multiport optical circulator (MOC) with fiber Bragg gratings are proposed and demonstrated. For the MOC-based structure, there is a sig nificant intraband crosstalk reduction of about 37 and 16 dB on the dropped and added channels, respectively, for the best proposed MOC-based structur e as compared with the conventional structure. Bit-error rate performance a nd both intraband and interband crosstalk-induced power penalties of these MOC-based OADMs are examined in a 10-Gb/s system demonstration. Such a low- crosstalk, miniaturized, and compact OADR I may find important applications in dense wavelength-division multiplexing networks.