OSNR Monitoring Method Based On Four Wave Mixing In High Linear Fiber

Intelligent optical network plays an important role in the future optical telecommunication network, which will take the place of the point to point communication today. In order to meet the flexibility and other features, ROADM is used, which brings a new challenge to optical performance monitoring, especially OSNR monitoring. As the traditional out-band OSNR monitoring can not gain the true OSNR value, the in-band OSNR monitoring method should be developed.In this article, one in-band OSNR monitoring method based FWM in HNLF is presented. In addition, the in-band OSNR monitoring method based on cascaded FWM also be demonstrated, and both of them are verified through simulation. The main work of this article is summarized in the following:(1) The development of intelligent optical network is introduced, and the drawback of out-band OSNR monitoring and the importance of in-band OSNR monitoring are demonstrated.(2) The main methods about in-band OSNR monitoring and their principle are analyzed, and the potential problem of each is pointed out.(3) The basic principle of FWM in HNLF and the related basic theory was introduced. Then the coupled amplitude equations are induced from non-linear Schrodinger equation, and build the FWM model on them.(4) The In-band OSNR monitoring method based on FWM in HNLF is proposed, and the basic principle was explained. The OSNR monitoring process was simulated, and it can commonly achieve 0dB-15dB range OSNR monitoring. (5) One in-band OSNR monitoring method based on cascaded FWM is presented. From the simulation, it shows a 0dB-20dB OSNR montitoring range. Finially, the monitoring pefermonce is optimized.