Operational window of single-mode optical fibers.

The purpose of this Ph.D. thesis is to define the design window of single-mode dispersion-unshifted fibers. This window, defined in the mode field diameter (MFD) and cutoff wavelength (lambda c) plot is determined by the fiber properties with regards to the chromatic dispersion, the bend loss sensitivity at 1550 nm and the modal noise penalty imposed on high speed operating systems. This has been achieved by developing numerical models used to analyze the properties of optical fibers. These models were used to calculate the propagation characteristics of optical fibers and from them their physical properties, such as the dispersion and bending loss of the fundamental mode. Similar programs, used in the calculations of the LP11 mode attenuation and bend performance, determined the fiber's modal noise sensitivity and from it the upper limit of cutoff wavelength