Research And Realization On Circuit Designing And Signal Processing Of Optical Network Performance Monitor

The optical network operator can acquire the direct information on the deteriorate grades of optics fiber-links and passive or active components, which inevitably happen during operating for a long time, through monitoring some characteristics parameters of optical channel signals using optical network performance monitor, such as drifting of center wavelength, fluctuating of optical power and optical signal-to-noise ratio (OSNR), and then some available measures can be adopt to process alarming, manage fault and further realize self-healing capability of network in advance. As the new network instrument, there are many issues required to investigate about Optical network performance monitor.As one part of the item named as"Researching and developing on smart optical network performance monitor (OPM)"sponsored by Shanghai Municipal Science and Technology Commission of China, This dissertation relates to some works that make OPM more smart and instrumental, thereinto, author has devoted herself to accomplishing designing and testing the optical-to-electric circuit, pre-amplifying circuit and data acquisition (DAQ) circuit with ADC; investigating signal processing algorithms including signal filtering and OSNR calculating, a new method of wavelet threshold de-noising that decomposing the original signal to 4 levels with db4 wavelet has been presented and the excellent de-noising algorithm has been obtained through mending original algorithm using curve fitting of nonlinear least square method, after fulfilling these new algorithms, filtering effects are optimized perfectly, subsequently, defining OSNR according to the characteristics of DWDM signal monitored by OPM and presenting the accurate method for calculating OSNR, these algorithms have been simulated, compiled and fulfilled based on the idea of mixed programming of MATLAB and LabVIEW; all the signal processing functions of OPM using LabVIEW programs have been realized as well as decent GUI, combining with the communication interface circuit based on ARM system, thus all the instrumental and smart functions of optical network performance monitor have been achieved; at last the data and debugging results of OPM system have been presented.