Wavelength Selective Devices for SDM Applications Based on SPOC Platform

The increase in communications network traffic has led to a demand for a larger transmission capacity. To meet this demand, the combination of wavelength division multiplexing (WDM) and space-division multiplexing (SDM) is being extensively investigated. Among various SDM systems, that based on multi-core fiber is attractive because network flexibility increases while it maintains the transmission capacity to be enlarged in proportion to the number of SDM channel number. However, problems arise because the number of input/output ports increases dramatically in optical nodes. To solve these problems, there is a novel optical configuration technology, the spatial and planar optical circuit (SPOC), which makes the integration of multiple WSSs and filters possible. The SPOC platform has been used to achieve variety of devices such as optical dispersion compensation and WSSs. One of the great advantages of SPOC platform is that we can integrate multiple optics of WSSs in a module, which contribute to miniaturization of devices. In this paper, we review the devices for SDM networks, which are realized with SPOC platform including WSS arrays, wavelength cross-connects (WXCs), multi-channel optical performance monitors, and its related technology.