Analyses And Research On PMD Compensation Technology In High Speed Optical Communication System

With the development of high speed,long distance optical communication system.The influence of the polarization mode dispersion(PMD)becomes more and more outstanding in single mode fiber,and PMD was considered to be the important restrictive factor of high speed and long distance optical transmission.PMD induces impulse broading and leads to inter-symbol interference,which impacts the quality of signal badly.Because of the impact of the circumstance,PMD shows statistical characterization,which makes the compensation of PMD becomes more difficult than chromatic dispersion.First,an analysis of the correlative concepts of PMD and its statistics nature was given, which are the fundamentals for farther discussion;Second,an expression of PMD-induced pulse broadening was derived based on principal state polarization(PSP),which is the description for first-order PMD;then discussed the deterioration of receiver's sensitivity caused by PMD and the effect of PMD on RF spectrum at the receiver;the experimental result was given for the latter;At last,a method of extracting a PMD error signal for PMD compensation was put forward from above analysis and experimental results.The main topic of the thesis is PMD compensation(PMDC)technology.First,the principle of first-order PMDC and a general model of PMDC was presented;then described main sub-model,respectively,and gave an analysis and comparison of present main PMD compensation or mitigation methods;An adapt PMD compensation system was constructed in order to compensate PMD.The specific emulation and experimental research of a first-order PMD compensator was implemented,including the analysis and description of compensator unit,the pick-up of feedback signal method and so forth.The emulation results showed that the PMD compensator designed had a good performance for compensating the PMD effect. Finally,the improvement and future prospects of PMDC was discussed.