DESIGN AND PERFORMANCE OF DELIVERY AND COUPLING SWITCH BOARD FOR LARGE-SCALE OPTICAL-PATH CROSS-CONNECT SYSTEM

This paper describes the recently developed 8x16 delivery and coupling switch (DC-switch) boards for constructing a 320-Gb/s throughput (2.5 Gb/s x 8 multiplexed wavelengths x 16 incoming/outgoing link pairs) o ptical path cross-connect (OPXC) system based on wavelength path (WP) and virtual wavelength path (VWP) schemes. The DC-switch-based OPXC sy stem, compared with conventional space division switch (SD-switch)-bas ed OPXC system architecture, is shown to be superior in terms of; i) h igh link modularity, ii) upgradability from WP network to VWP network, iii) better transmission characteristics, and iv) lower total switchi ng power consumption. Therefore, the DC-switch-based OPXC system can r ealize cost-effective optical path networks. The developed DC-switches exploit the silica-based planar lightwave circuit (PLC) technologies, and DC-switch board size is 300x330 mm(2) (one switch). The worst val ues of the insertion loss of the board, ON/OFF ratio, and polarization dependent loss are 14.5 dB, 34 dB and 0.5 dB, respectively. Moreover, even though switching is realized by thermo-optic effects, the optica l output level varies by only 0.7 dB and 0.8 dB for ON- and OFF state signals, respectively, when the environmental temperature is varied fr om 5 to 65 degrees C.