Performances of an optical path cross-connect system and its wavelength monitoring circuit

This paper describes the performances of a newly-developed experimental optical path cross-connect system (OPXC) based on the wavelength path scheme and its wavelength monitoring circuit. The OPXC system features high levels of modularity and expandability for switching components. Exploiting planar lightwave circuit (PLC) technologies, (8×16) delivery-and-coupling-type optical switches (DC-switch) are fabricated for the 320-Gbit/s throughput OPXC system which can accommodate 16 incoming and outgoing fibers. The average fiber-to-fiber insertion loss of the DC switch is 12.6 dB and its on/off ratio is 42.1 dB. Eight wavelength-division multiplexing (WDM) signals, directly intensity-modulated at 2.5 Gbit/s, are performed to be transported over 330 km from origin to destination node via a cross-connection node in the test-bed system which simulates a 5-node network. Additionally, a novel multiwavelength simultaneous monitoring circuit for the OPXC is proposed and its performance is demonstrated through experiments