Optical Performance Monitoring Of Super-Channel Based On Advanced Modulation Mode

In order to meet the growing demand of bandwidth, Super-Channel with ltra-high speed and large capacity is becoming the main development direction of optical network in the future. With the improvement of transmission rate and channel capacity, the tolerance of transmission damage reduces sharply. Thus, nonlinear optical fiber, dispersion(CD), optical signal-to-noise ratio(OSNR) and polarization mode dispersion(PMD) have a deeper damage on the system. For the purpose of strengthening the management of Super-Channel online, optical performance monitoring is necessary, which can provide theoretical basis for the optimization of optical channel.In this paper, the research of monitoring the performance of Supper-Channel includes the following aspects. Firstly, a novel technology for monitoring the Supper-Channel, based on mode switching with multi-granularity- optical cross-connects(MG-OXC) is proposed, whose switching nodes can realize not only optical switching,waveband switching and wavelength switching, but also mode switching. Therefore, the dispersion and nonlinear between any modes of the nodes can be monitored online and the balance of power different modes can easily achieved. On the basis of theory, a preliminary experimental monitoring system is set up, which can realize 7×7 optical switching, 7×7 mode switching and monitor the switching nodes. Secondly, because the asynchronous amplitude figure(AAH) has the advantages of the transparency of format and rate, low cost and easy to implement, a novel chromatic dispersion(CD) monitoring technique based on asynchronous amplitude sampling(AAS) for higher modulation formats and higher rate system is proposed in this paper. The relationship between signals and noise is derived based on the first and third order origin moment of samples. The parameters M4 and M6 are defined so that the dispersion and other impairment factors can be separated with the definition of monitoring parameters MCDR. 400Gb/s 256 QAM system is built using MATLAB and Optisystem13.0 beta software. Simulations of CD monitoring technique for different bandwidths of sampling Gaussian filter, signal to noise ratio and duty cycle monitoring is investigated, and the tolerance is also discussed. Simulation results shows that the method can be less affected by noise and high accuracy can be achieved at 0 ~ 600ps/nm. The technique supports a wide range of data traffic and enhances operation flexibility optical networks.