Can Be Reconstructed Optical Add-drop Multiplexer

Dense Wavelength Division Multiplexing (DWDM) system is a most familiar technology to construct the network in optical layer. However, traditional WDM system is a point to point transport system. Constructing network in optical layer is mostly implemented by optical line which is composed of Terminal station(TM) and Optical Add/Drop Multiplexer (OADM). But due to the limited function of OADM, the number and wavelength of optical channels which is added/dropped by OADM is fixed. The flexible constructing network in optical layer is not really realized. At present the reconfigurable OADM can dynamically adjust add/drop channel's wavelength by remote configuration from network management unit, it realized flexible allocation and dynamic reconstruct of wavelength source in network, and made the more sufficient use of wavelength source in network. The core of constructing network from back-to-back OTM to OADM of fixed wavelength add/drop and further to the step by step transition to reconfigurable OADM is foreseeable and best feasible developmental course and direction for DWDM network.ROADM(Reconfigurable OADM) not only greatly simplifies the demand of earlier layout for network and more effectively made use of bandwidth source, but also makes the protection and recovery of network stronger and more effective. ROADM is an important ladder for transport network's striding to the next generation intelligent entire optical net。In this paper, the basic principle and component of ROADM are described. A kind of solution for ROAM based on the WSS technology is given. The paper also explains the DWDM principle and architecture, analyses the defect of traditional DWDM system, and discusses the advantage of system with ROADM. The pape also gives what I do in the design of ROADM line card in DWDM system, and provides the result after choosing WSS technology in the design.