| Nowadays, with the increase of data service requirement, the improvement of communication speed and capacity will definitely become the major objective of network upgrade. The rate bottleneck problems of electronic device have been solved after putting forward the concept of all-optical networks. Meanwhile, because of mature of long dense wavelength division multiplexed (DWDM) transmission system, the demand of improving communication capacity has been solved. At the same time, under the complex network topology, the problems of bandwidth management and wavelength dispatching become more prominent. Wavelength blockers (WB) are optical device that accept incoming signal of multiple wavelength channels and independently pass or block each wavelength channel.In all-optical network, WB that achieved flat gain and balanced power is the key technology. In this paper the wavelength blocker based on liquid crystal used the principle of difference voltage coming up with difference polarization state. Optical signal channels attenuation having a frequency separation of 100GHz is realized. This paper is divided into six parts:1.Introduce the evolution of ROADM and ROADM technology based on WB. Analyze WB application in DWDM system;2.Describe theoretical knowledge, analyze electro-optic effect (EOE) and temperature characteristics of liquid crystal;3.Deduce two implementations of WB.Design optical patch and analyze the role of each part;4. Design hardware and software as the optical requirement.Test the performance of circuit;5.Verify the function of whole module. Test temperature stability and optical index.Analyze the problems and propose solutions;6.Summarize and expect the whole paper. |
