The Study Of Performance Of Decreasing Dispersion Fibers

Comparing to the common fiber, dispersion decreasing fiber (DDF), which is a new special fiber, has peculiar performance and use. And it has prominent advantage in the aspect of pulse compression and soiiton-chaurs coming into being. So, many scholars pay a lot of attention to DDF research.In this thesis the gain spectrum of modulation instability (MI) is calculated theoretically, and the MI in different DDF is studied. Then pulse's evolvement in different DDF is simulated by means of numerical method. The results show that the performance of DDF communication system is much better than common fiber in the aspect of not only pulse transmission without aberration but also pulse compression. Moreover, different DDF has respective advantage in different application area. It provides the scientific gist to exert the optimum performance of different type of DDF in practice.In the end, the influences of polarization mode dispersion (PMD) on DDF communication system are studied. It found that PMD is one of the ultimately limiting factors and must be compensated in practice.