Research On Emulation And Compensation Technology Of Polarization Mode Dispersion

When attenuation and chromatic dispersion are compensated for, PMD is regarded as one of the dominant obstacles in optical fiber communication systems having bit rates of 40Gbit/s and beyond. Research found that PMD can damage the performance of system and limit the transmission distance. However, PMD is more difficult to compensate than other compensation because of its stochastic feature. PMD becomes more and more projecting. The thesis studies leadingly emulator of PMD and the compensation method of PMD.First the thesis introduces investigative background of task,investigative importance and research situation both here and abroad. It introduces causes of formation of polarization mode dispersion(PMD),describing methods in internet and some important concepts about PMD,for example double refraction, coupling, primary polarization state and so on. Soon after the thesis researches that PMD effects optical communication system. It researches on pulse widening which caused by PMD, worsen to sensitivity of receiver, influence on receiver frequency spectrum by computer emulation. By analyzing results , it chooses that putting efficiency of a part frequency spectrum of receiving signal as controlling signal. It researches and analyzes that how to choose suitable controlling signal about different systems. Next and it researches an emulation, analyzes the relation of the number of polarization-preserving fiber and property of emulation. Finally, it experiments that PMD compensation for 40Gbit/s optical transmission system. And choosing 20GHz power as controlling signal to compensate PMD. Experiment makes clear that the frequency which the thesis chooses is able to compensate PMD.