Different aspects of the polarization mode dispersion measuring technique

摘要

We have presented a short overview of instruments which allow the PMD of standard Telekom fibers, but also of advanced fibers to be determined. We described two set-ups in more detail which belong to the complementary pictures of frequency and time domains. Both mean values, representing a Maxwellian and a Gaussian distribution, agree more or less satisfactorily. It has been shown that the mean values are stable, reproducible, suitable for interlaboratory measuring comparisons and can be regarded as a parameter which characterizes SM fibers. The polarimeter measuring principle allows physically interesting effects to be investigated, including studies of ultralong transmission hauls with ED-FAs.It has been demonstrated that it is possible to avoid the PMD in cables. It is necessary to clarify the reason. With a low probability, very high PMD values exist for special wavelengths and SOPs - representing the distant part of the tail of the Maxwellian distribution which are stable for a short time. Their influence on the BER of ultralong, high-bit rate systems has to be investigated.