Research Of Optical Performance Monitoring Technology For Multiple Impairments

The development of E-commerce,distributed cloud computing,online live video broadcast and other new Internet services,promoted the demand of data center and large capacity data network for modern information society,which caused an explosive growth in the construction of optical communication network.Optical network will gradually trend toward the large capacity,dynamic and re-configurable intelligent all-optical networks in the future.This also poses a new challenge to guarantee the service quality of users' network,so it is necessary to evaluate the quality of the optical signal,to monitor the damage degree of the transmission signal and to compensate in time.Optical Performance Monitoring is an important basic research which provides the performance guarantee and network management for the future dynamic optical network,and one of the key technologies in the next generation optical network.Firstly,this thesis elaborates the function and significance of Optical Performance Monitoring and discussed the challenge and difficulty might be faced for future Optical Performance Monitoring technology.It needs to distinguish and monitor multiple impairment types simultaneously.However,it is comparatively difficult to distinguish the effects of different damage parameters from the received signal on the receiving end.Thus,this article explain from the basic concept and system of tolerance about detailed description of the optical signal-to-noise ratio,dispersion and polarization mode dispersion of the three kinds of impairments.Secondly,the traditional monitor solution usually can only realize monitoring single parameter,and mainly discussed the monitoring scope and the dynamic range of output.However,in the monitoring process of single damage parameter,it almost always effected by other impairment factor and obscured the monitor results.Aiming at the problem of the multi-parameter simultaneous monitoring,this thesis proposed a three-port simultaneously monitoring solution for multiple impairments through the research of radio spectrum analysis technology in an innovative way.The three parameters mentioned above are monitored by the low frequency uncorrelated beat noise,the power ratio of double sideband and the single sideband radio frequency spectrum and the clock component of the RF signal.Because of the adjustment of the filter structure in the uncorrelated beat noise method,the proposed method can re-use the device in one branch of the uncorrelated beat noise monitoring method to extract the clock component in the RF spectrum.It reduces the size and cost of the monitoring module to some extent,which is beneficial to the module integration in the future.Finally,because the RF spectrum analysis method requires photoelectric detection,which suffer the photoelectric bottleneck at detecting speed.Therefore,this paper continues to the research of all-optical monitoring technology,which is directly monitoring the impairment in optical domain.By using the power transfer function of four-wave mixing,the impairment effect of the optical transmission signal is mapped to the newly generated idler light in four-wave mixing,so that it can be realized to monitor the impairments of transmission signal by measuring the power of the idler light.