
Another physical phenomenon in the fiber, which can severely degrade the
system quality, is polarization mode dispersion (PMD) [6]. Because fibers have
circular profiles, models tend to overlook the fact that the electric field is better
represented by a vector. This approximation is generally true, but should
imperfections alter the fiber composition or local geometry during manufactur-
ing, the two polarization components of the electric field may travel at different
speeds causing pulse broadening or even pulse splitting at the end an optical
link, as illustrated in the example in Figure 14.4. The acronym PMD designates
both the physical phenomenon ...